Merge branch 'main' into pyMaD

.github/labeler.yml

@@ -11,7 +11,7 @@ Java:
   - change-notes/**/*java.*
 
 JS:
-  - javascript/**/*
+  - any: [ 'javascript/**/*', '!javascript/ql/experimental/adaptivethreatmodeling/**/*' ]
   - change-notes/**/*javascript*
 
 Python:

.github/workflows/codeql-analysis.yml

@@ -30,7 +30,7 @@ jobs:
     - name: Setup dotnet
       uses: actions/setup-dotnet@v2
       with:
-        dotnet-version: 6.0.101
+        dotnet-version: 6.0.202
 
     - name: Checkout repository
       uses: actions/checkout@v3

.github/workflows/query-list.yml

@@ -30,20 +30,15 @@ jobs:
       with:
         python-version: 3.8
     - name: Download CodeQL CLI
-      uses: dsaltares/fetch-gh-release-asset@aa37ae5c44d3c9820bc12fe675e8670ecd93bd1c
-      with:
-        repo: "github/codeql-cli-binaries"
-        version: "latest"
-        file: "codeql-linux64.zip"
-        token: ${{ secrets.GITHUB_TOKEN }}
+      # Look under the `codeql` directory, as this is where we checked out the `github/codeql` repo
+      uses: ./codeql/.github/actions/fetch-codeql
     - name: Unzip CodeQL CLI
       run: unzip -d codeql-cli codeql-linux64.zip
     - name: Build code scanning query list
       run: |
-        PATH="$PATH:codeql-cli/codeql" python codeql/misc/scripts/generate-code-scanning-query-list.py > code-scanning-query-list.csv
+        python codeql/misc/scripts/generate-code-scanning-query-list.py > code-scanning-query-list.csv
     - name: Upload code scanning query list
       uses: actions/upload-artifact@v3
       with:
         name: code-scanning-query-list
         path: code-scanning-query-list.csv
-    

.gitignore

@@ -37,5 +37,8 @@ csharp/extractor/Semmle.Extraction.CSharp.Driver/Properties/launchSettings.json
 # links created by bazel
 /bazel-*
 
+# local bazel options
+/local.bazelrc
+
 # CLion project files
 /.clwb

CODEOWNERS

@@ -4,6 +4,9 @@
 /javascript/ @github/codeql-javascript
 /python/ @github/codeql-python
 /ruby/ @github/codeql-ruby
+/swift/ @github/codeql-c
+/java/kotlin-extractor/ @github/codeql-kotlin
+/java/kotlin-explorer/ @github/codeql-kotlin
 
 # ML-powered queries
 /javascript/ql/experimental/adaptivethreatmodeling/ @github/codeql-ml-powered-queries-reviewers

cpp/ql/lib/CHANGELOG.md

@@ -1,3 +1,14 @@
+## 0.2.0
+
+### Breaking Changes
+
+* The signature of `allowImplicitRead` on `DataFlow::Configuration` and `TaintTracking::Configuration` has changed from `allowImplicitRead(DataFlow::Node node, DataFlow::Content c)` to `allowImplicitRead(DataFlow::Node node, DataFlow::ContentSet c)`.
+
+### Minor Analysis Improvements
+
+* More Windows pool allocation functions are now detected as `AllocationFunction`s.
+* The `semmle.code.cpp.commons.Buffer` library has been enhanced to handle array members of classes that do not specify a size.
+
 ## 0.1.0
 
 ### Breaking Changes

cpp/ql/lib/change-notes/2022-04-22-no-size-array.md

@@ -1,4 +0,0 @@
----
-category: minorAnalysis
----
-* The `semmle.code.cpp.commons.Buffer` library has been enhanced to handle array members of classes that do not specify a size.

cpp/ql/lib/change-notes/2022-04-25-allow-implicit-read-signature.md

@@ -1,4 +0,0 @@
----
-category: breaking
----
-The signature of `allowImplicitRead` on `DataFlow::Configuration` and `TaintTracking::Configuration` has changed from `allowImplicitRead(DataFlow::Node node, DataFlow::Content c)` to `allowImplicitRead(DataFlow::Node node, DataFlow::ContentSet c)`.

cpp/ql/lib/change-notes/2022-04-25-windows-pool-allocation-functions.md

@@ -1,4 +0,0 @@
----
-category: minorAnalysis
----
-* More Windows pool allocation functions are now detected as `AllocationFunction`s.

cpp/ql/lib/change-notes/2022-05-11-deprecated-analysed-string.md

@@ -0,0 +1,4 @@
+---
+ category: deprecated
+---
+ * The `AnalysedString` class in the `StringAnalysis` module has been replaced with `AnalyzedString`, to follow our style guide. The old name still exists as a deprecated alias.

cpp/ql/lib/change-notes/released/0.2.0.md

@@ -0,0 +1,10 @@
+## 0.2.0
+
+### Breaking Changes
+
+* The signature of `allowImplicitRead` on `DataFlow::Configuration` and `TaintTracking::Configuration` has changed from `allowImplicitRead(DataFlow::Node node, DataFlow::Content c)` to `allowImplicitRead(DataFlow::Node node, DataFlow::ContentSet c)`.
+
+### Minor Analysis Improvements
+
+* More Windows pool allocation functions are now detected as `AllocationFunction`s.
+* The `semmle.code.cpp.commons.Buffer` library has been enhanced to handle array members of classes that do not specify a size.

cpp/ql/lib/codeql-pack.release.yml

@@ -1,2 +1,2 @@
 ---
-lastReleaseVersion: 0.1.0
+lastReleaseVersion: 0.2.0

cpp/ql/lib/qlpack.yml

@@ -1,5 +1,5 @@
 name: codeql/cpp-all
-version: 0.1.1-dev
+version: 0.2.1-dev
 groups: cpp
 dbscheme: semmlecode.cpp.dbscheme
 extractor: cpp

cpp/ql/lib/semmle/code/cpp/Function.qll

@@ -38,8 +38,8 @@ class Function extends Declaration, ControlFlowNode, AccessHolder, @function {
    * int z = min(5, 7);
    * ```
    * The full signature of the function called on the last line would be
-   * "min<int>(int, int) -> int", and the full signature of the uninstantiated
-   * template on the first line would be "min<T>(T, T) -> T".
+   * `min<int>(int, int) -> int`, and the full signature of the uninstantiated
+   * template on the first line would be `min<T>(T, T) -> T`.
    */
   string getFullSignature() {
     exists(string name, string templateArgs, string args |

cpp/ql/lib/semmle/code/cpp/commons/Printf.qll

@@ -1312,7 +1312,7 @@ class FormatLiteral extends Literal {
         len =
           min(int v |
             v = this.getPrecision(n) or
-            v = this.getUse().getFormatArgument(n).(AnalysedString).getMaxLength() - 1 // (don't count null terminator)
+            v = this.getUse().getFormatArgument(n).(AnalyzedString).getMaxLength() - 1 // (don't count null terminator)
           ) and
         reason = TValueFlowAnalysis()
       )

cpp/ql/lib/semmle/code/cpp/commons/StringAnalysis.qll

@@ -27,11 +27,14 @@ predicate canValueFlow(Expr fromExpr, Expr toExpr) {
   fromExpr = toExpr.(ConditionalExpr).getElse()
 }
 
+/** DEPRECATED: Alias for AnalyzedString */
+deprecated class AnalysedString = AnalyzedString;
+
 /**
- * An analysed null terminated string.
+ * An analyzed null terminated string.
  */
-class AnalysedString extends Expr {
-  AnalysedString() {
+class AnalyzedString extends Expr {
+  AnalyzedString() {
     this.getUnspecifiedType() instanceof ArrayType or
     this.getUnspecifiedType() instanceof PointerType
   }
@@ -41,15 +44,15 @@ class AnalysedString extends Expr {
    * can be calculated.
    */
   int getMaxLength() {
-    // take the longest AnalysedString it's value could 'flow' from; however if even one doesn't
+    // take the longest AnalyzedString its value could 'flow' from; however if even one doesn't
     // return a value (this essentially means 'infinity') we can't return a value either.
     result =
-      max(AnalysedString expr, int toMax |
+      max(AnalyzedString expr, int toMax |
         canValueFlow*(expr, this) and toMax = expr.(StringLiteral).getOriginalLength()
       |
         toMax
       ) and // maximum length
-    forall(AnalysedString expr | canValueFlow(expr, this) | exists(expr.getMaxLength())) // all sources return a value (recursive)
+    forall(AnalyzedString expr | canValueFlow(expr, this) | exists(expr.getMaxLength())) // all sources return a value (recursive)
   }
 }
 

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImpl.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImpl2.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImpl3.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImpl4.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImplCommon.qll

@@ -328,6 +328,9 @@ private module Cached {
   cached
   predicate clearsContentCached(Node n, ContentSet c) { clearsContent(n, c) }
 
+  cached
+  predicate expectsContentCached(Node n, ContentSet c) { expectsContent(n, c) }
+
   cached
   predicate isUnreachableInCallCached(Node n, DataFlowCall call) { isUnreachableInCall(n, call) }
 

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowImplLocal.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/dataflow/internal/DataFlowPrivate.qll

@@ -198,6 +198,12 @@ predicate clearsContent(Node n, Content c) {
   none() // stub implementation
 }
 
+/**
+ * Holds if the value that is being tracked is expected to be stored inside content `c`
+ * at node `n`.
+ */
+predicate expectsContent(Node n, ContentSet c) { none() }
+
 /** Gets the type of `n` used for type pruning. */
 Type getNodeType(Node n) {
   suppressUnusedNode(n) and

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl2.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl3.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImpl4.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowImplCommon.qll

@@ -328,6 +328,9 @@ private module Cached {
   cached
   predicate clearsContentCached(Node n, ContentSet c) { clearsContent(n, c) }
 
+  cached
+  predicate expectsContentCached(Node n, ContentSet c) { expectsContent(n, c) }
+
   cached
   predicate isUnreachableInCallCached(Node n, DataFlowCall call) { isUnreachableInCall(n, call) }
 

cpp/ql/lib/semmle/code/cpp/ir/dataflow/internal/DataFlowPrivate.qll

@@ -279,6 +279,12 @@ predicate clearsContent(Node n, Content c) {
   none() // stub implementation
 }
 
+/**
+ * Holds if the value that is being tracked is expected to be stored inside content `c`
+ * at node `n`.
+ */
+predicate expectsContent(Node n, ContentSet c) { none() }
+
 /** Gets the type of `n` used for type pruning. */
 IRType getNodeType(Node n) {
   suppressUnusedNode(n) and

cpp/ql/lib/semmle/code/cpp/security/BufferWrite.qll

@@ -155,7 +155,7 @@ class StrCopyBW extends BufferWriteCall {
     // when result exists, it is an exact flow analysis
     reason instanceof ValueFlowAnalysis and
     result =
-      this.getArgument(this.getParamSrc()).(AnalysedString).getMaxLength() * this.getCharSize()
+      this.getArgument(this.getParamSrc()).(AnalyzedString).getMaxLength() * this.getCharSize()
   }
 
   override int getMaxData(BufferWriteEstimationReason reason) {
@@ -201,7 +201,7 @@ class StrCatBW extends BufferWriteCall {
     // when result exists, it is an exact flow analysis
     reason instanceof ValueFlowAnalysis and
     result =
-      this.getArgument(this.getParamSrc()).(AnalysedString).getMaxLength() * this.getCharSize()
+      this.getArgument(this.getParamSrc()).(AnalyzedString).getMaxLength() * this.getCharSize()
   }
 
   override int getMaxData(BufferWriteEstimationReason reason) {

cpp/ql/lib/semmle/code/cpp/security/Overflow.qll

@@ -5,8 +5,6 @@
 
 import cpp
 import semmle.code.cpp.controlflow.Dominance
-// `GlobalValueNumbering` is only imported to prevent IR re-evaluation.
-private import semmle.code.cpp.valuenumbering.GlobalValueNumbering
 import semmle.code.cpp.rangeanalysis.SimpleRangeAnalysis
 import semmle.code.cpp.rangeanalysis.RangeAnalysisUtils
 import semmle.code.cpp.controlflow.Guards

cpp/ql/src/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 0.1.1
+
+### New Queries
+
+* An new query `cpp/external-entity-expansion` has been added. The query detects XML objects that are vulnerable to external entity expansion (XXE) attacks.
+
 ## 0.1.0
 
 ### Minor Analysis Improvements

cpp/ql/src/Likely Bugs/Memory Management/ReturnStackAllocatedMemory.ql

@@ -14,9 +14,6 @@
  */
 
 import cpp
-// We don't actually use the global value numbering library in this query, but without it we end up
-// recomputing the IR.
-private import semmle.code.cpp.valuenumbering.GlobalValueNumbering
 import semmle.code.cpp.ir.IR
 import semmle.code.cpp.ir.dataflow.MustFlow
 import PathGraph

cpp/ql/src/Likely Bugs/Memory Management/SuspiciousCallToMemset.ql

@@ -2,7 +2,7 @@
  * @name Suspicious call to memset
  * @description Use of memset where the size argument is computed as the size of
  *              some non-struct type. When initializing a buffer, you should specify
- *              its size as <number of elements> * <size of one element> to ensure
+ *              its size as `<number of elements> * <size of one element>` to ensure
  *              portability.
  * @kind problem
  * @id cpp/suspicious-call-to-memset

cpp/ql/src/Likely Bugs/OO/UnsafeUseOfThis.ql

@@ -15,9 +15,6 @@
  */
 
 import cpp
-// We don't actually use the global value numbering library in this query, but without it we end up
-// recomputing the IR.
-import semmle.code.cpp.valuenumbering.GlobalValueNumbering
 import semmle.code.cpp.ir.IR
 import semmle.code.cpp.ir.dataflow.MustFlow
 import PathGraph

cpp/ql/src/Security/CWE/CWE-611/XXE.ql

@@ -16,6 +16,7 @@ import cpp
 import semmle.code.cpp.ir.dataflow.DataFlow
 import DataFlow::PathGraph
 import semmle.code.cpp.ir.IR
+import semmle.code.cpp.valuenumbering.GlobalValueNumbering
 
 /**
  * A flow state representing a possible configuration of an XML object.
@@ -57,42 +58,58 @@ class XercesDOMParserClass extends Class {
 }
 
 /**
- * Gets a valid flow state for `XercesDOMParser` flow.
+ * The `SAXParser` class.
+ */
+class SaxParserClass extends Class {
+  SaxParserClass() { this.hasName("SAXParser") }
+}
+
+/**
+ * The `SAX2XMLReader` class.
+ */
+class Sax2XmlReader extends Class {
+  Sax2XmlReader() { this.hasName("SAX2XMLReader") }
+}
+
+/**
+ * Gets a valid flow state for `AbstractDOMParser` or `SAXParser` flow.
  *
- * These flow states take the form `XercesDOM-A-B`, where:
+ * These flow states take the form `Xerces-A-B`, where:
  *  - A is 1 if `setDisableDefaultEntityResolution` is `true`, 0 otherwise.
  *  - B is 1 if `setCreateEntityReferenceNodes` is `true`, 0 otherwise.
  */
-predicate encodeXercesDOMFlowState(
+predicate encodeXercesFlowState(
   string flowstate, int disabledDefaultEntityResolution, int createEntityReferenceNodes
 ) {
-  flowstate = "XercesDOM-0-0" and
+  flowstate = "Xerces-0-0" and
   disabledDefaultEntityResolution = 0 and
   createEntityReferenceNodes = 0
   or
-  flowstate = "XercesDOM-0-1" and
+  flowstate = "Xerces-0-1" and
   disabledDefaultEntityResolution = 0 and
   createEntityReferenceNodes = 1
   or
-  flowstate = "XercesDOM-1-0" and
+  flowstate = "Xerces-1-0" and
   disabledDefaultEntityResolution = 1 and
   createEntityReferenceNodes = 0
   or
-  flowstate = "XercesDOM-1-1" and
+  flowstate = "Xerces-1-1" and
   disabledDefaultEntityResolution = 1 and
   createEntityReferenceNodes = 1
 }
 
 /**
- * A flow state representing the configuration of a `XercesDOMParser` object.
+ * A flow state representing the configuration of an `AbstractDOMParser` or
+ * `SAXParser` object.
  */
-class XercesDOMParserFlowState extends XXEFlowState {
-  XercesDOMParserFlowState() { encodeXercesDOMFlowState(this, _, _) }
+class XercesFlowState extends XXEFlowState {
+  XercesFlowState() { encodeXercesFlowState(this, _, _) }
 }
 
 /**
  * A flow state transformer for a call to
- * `AbstractDOMParser.setDisableDefaultEntityResolution`. Transforms the flow
+ * `AbstractDOMParser.setDisableDefaultEntityResolution` or
+ * `SAXParser.setDisableDefaultEntityResolution`. Transforms the flow
  * state through the qualifier according to the setting in the parameter.
  */
 class DisableDefaultEntityResolutionTranformer extends XXEFlowStateTranformer {
@@ -101,7 +118,10 @@ class DisableDefaultEntityResolutionTranformer extends XXEFlowStateTranformer {
   DisableDefaultEntityResolutionTranformer() {
     exists(Call call, Function f |
       call.getTarget() = f and
-      f.getDeclaringType() instanceof AbstractDOMParserClass and
+      (
+        f.getDeclaringType() instanceof AbstractDOMParserClass or
+        f.getDeclaringType() instanceof SaxParserClass
+      ) and
       f.hasName("setDisableDefaultEntityResolution") and
       this = call.getQualifier() and
       newValue = call.getArgument(0)
@@ -110,13 +130,13 @@ class DisableDefaultEntityResolutionTranformer extends XXEFlowStateTranformer {
 
   final override XXEFlowState transform(XXEFlowState flowstate) {
     exists(int createEntityReferenceNodes |
-      encodeXercesDOMFlowState(flowstate, _, createEntityReferenceNodes) and
+      encodeXercesFlowState(flowstate, _, createEntityReferenceNodes) and
       (
-        newValue.getValue().toInt() = 1 and // true
-        encodeXercesDOMFlowState(result, 1, createEntityReferenceNodes)
+        globalValueNumber(newValue).getAnExpr().getValue().toInt() = 1 and // true
+        encodeXercesFlowState(result, 1, createEntityReferenceNodes)
         or
-        not newValue.getValue().toInt() = 1 and // false or unknown
-        encodeXercesDOMFlowState(result, 0, createEntityReferenceNodes)
+        not globalValueNumber(newValue).getAnExpr().getValue().toInt() = 1 and // false or unknown
+        encodeXercesFlowState(result, 0, createEntityReferenceNodes)
       )
     )
   }
@@ -133,8 +153,7 @@ class CreateEntityReferenceNodesTranformer extends XXEFlowStateTranformer {
   CreateEntityReferenceNodesTranformer() {
     exists(Call call, Function f |
       call.getTarget() = f and
-      f.getDeclaringType() instanceof AbstractDOMParserClass and
-      f.hasName("setCreateEntityReferenceNodes") and
+      f.getClassAndName("setCreateEntityReferenceNodes") instanceof AbstractDOMParserClass and
       this = call.getQualifier() and
       newValue = call.getArgument(0)
     )
@@ -142,27 +161,76 @@ class CreateEntityReferenceNodesTranformer extends XXEFlowStateTranformer {
 
   final override XXEFlowState transform(XXEFlowState flowstate) {
     exists(int disabledDefaultEntityResolution |
-      encodeXercesDOMFlowState(flowstate, disabledDefaultEntityResolution, _) and
+      encodeXercesFlowState(flowstate, disabledDefaultEntityResolution, _) and
       (
-        newValue.getValue().toInt() = 1 and // true
-        encodeXercesDOMFlowState(result, disabledDefaultEntityResolution, 1)
+        globalValueNumber(newValue).getAnExpr().getValue().toInt() = 1 and // true
+        encodeXercesFlowState(result, disabledDefaultEntityResolution, 1)
         or
-        not newValue.getValue().toInt() = 1 and // false or unknown
-        encodeXercesDOMFlowState(result, disabledDefaultEntityResolution, 0)
+        not globalValueNumber(newValue).getAnExpr().getValue().toInt() = 1 and // false or unknown
+        encodeXercesFlowState(result, disabledDefaultEntityResolution, 0)
       )
     )
   }
 }
 
 /**
- * The `AbstractDOMParser.parse` method.
+ * The `XMLUni.fgXercesDisableDefaultEntityResolution` constant.
  */
-class ParseFunction extends Function {
-  ParseFunction() { this.getClassAndName("parse") instanceof AbstractDOMParserClass }
+class FeatureDisableDefaultEntityResolution extends Variable {
+  FeatureDisableDefaultEntityResolution() {
+    this.getName() = "fgXercesDisableDefaultEntityResolution" and
+    this.getDeclaringType().getName() = "XMLUni"
+  }
 }
 
 /**
- * The `createLSParser` function that returns a newly created `LSParser` object.
+ * A flow state transformer for a call to `SAX2XMLReader.setFeature`
+ * specifying the feature `XMLUni::fgXercesDisableDefaultEntityResolution`.
+ * Transforms the flow state through the qualifier according to this setting.
+ */
+class SetFeatureTranformer extends XXEFlowStateTranformer {
+  Expr newValue;
+
+  SetFeatureTranformer() {
+    exists(Call call, Function f |
+      call.getTarget() = f and
+      f.getClassAndName("setFeature") instanceof Sax2XmlReader and
+      this = call.getQualifier() and
+      globalValueNumber(call.getArgument(0)).getAnExpr().(VariableAccess).getTarget() instanceof
+        FeatureDisableDefaultEntityResolution and
+      newValue = call.getArgument(1)
+    )
+  }
+
+  final override XXEFlowState transform(XXEFlowState flowstate) {
+    exists(int createEntityReferenceNodes |
+      encodeXercesFlowState(flowstate, _, createEntityReferenceNodes) and
+      (
+        globalValueNumber(newValue).getAnExpr().getValue().toInt() = 1 and // true
+        encodeXercesFlowState(result, 1, createEntityReferenceNodes)
+        or
+        not globalValueNumber(newValue).getAnExpr().getValue().toInt() = 1 and // false or unknown
+        encodeXercesFlowState(result, 0, createEntityReferenceNodes)
+      )
+    )
+  }
+}
+
+/**
+ * The `AbstractDOMParser.parse`, `SAXParser.parse` or `SAX2XMLReader.parse`
+ * method.
+ */
+class ParseFunction extends Function {
+  ParseFunction() {
+    this.getClassAndName("parse") instanceof AbstractDOMParserClass or
+    this.getClassAndName("parse") instanceof SaxParserClass or
+    this.getClassAndName("parse") instanceof Sax2XmlReader
+  }
+}
+
+/**
+ * The `createLSParser` function that returns a newly created `DOMLSParser`
+ * object.
  */
 class CreateLSParser extends Function {
   CreateLSParser() {
@@ -171,6 +239,53 @@ class CreateLSParser extends Function {
   }
 }
 
+/**
+ * The `createXMLReader` function that returns a newly created `SAX2XMLReader`
+ * object.
+ */
+class CreateXmlReader extends Function {
+  CreateXmlReader() {
+    this.hasName("createXMLReader") and
+    this.getUnspecifiedType().(PointerType).getBaseType() instanceof Sax2XmlReader // returns a `SAX2XMLReader *`.
+  }
+}
+
+/**
+ * A call to a `libxml2` function that parses XML.
+ */
+class Libxml2ParseCall extends FunctionCall {
+  int optionsArg;
+
+  Libxml2ParseCall() {
+    exists(string fname | this.getTarget().getName() = fname |
+      fname = "xmlCtxtUseOptions" and optionsArg = 1
+      or
+      fname = "xmlReadFile" and optionsArg = 2
+      or
+      fname = ["xmlCtxtReadFile", "xmlParseInNodeContext", "xmlReadDoc", "xmlReadFd"] and
+      optionsArg = 3
+      or
+      fname = ["xmlCtxtReadDoc", "xmlCtxtReadFd", "xmlReadMemory"] and optionsArg = 4
+      or
+      fname = ["xmlCtxtReadMemory", "xmlReadIO"] and optionsArg = 5
+      or
+      fname = "xmlCtxtReadIO" and optionsArg = 6
+    )
+  }
+
+  /**
+   * Gets the argument that specifies `xmlParserOption`s.
+   */
+  Expr getOptions() { result = this.getArgument(optionsArg) }
+}
+
+/**
+ * An `xmlParserOption` for `libxml2` that is considered unsafe.
+ */
+class Libxml2BadOption extends EnumConstant {
+  Libxml2BadOption() { this.getName() = ["XML_PARSE_NOENT", "XML_PARSE_DTDLOAD"] }
+}
+
 /**
  * A configuration for tracking XML objects and their states.
  */
@@ -184,14 +299,47 @@ class XXEConfiguration extends DataFlow::Configuration {
       call.getStaticCallTarget() = any(XercesDOMParserClass c).getAConstructor() and
       node.asInstruction().(WriteSideEffectInstruction).getDestinationAddress() =
         call.getThisArgument() and
-      encodeXercesDOMFlowState(flowstate, 0, 1) // default configuration
+      encodeXercesFlowState(flowstate, 0, 1) // default configuration
     )
     or
     // source is the result of a call to `createLSParser`.
     exists(Call call |
       call.getTarget() instanceof CreateLSParser and
       call = node.asExpr() and
-      encodeXercesDOMFlowState(flowstate, 0, 1) // default configuration
+      encodeXercesFlowState(flowstate, 0, 1) // default configuration
+    )
+    or
+    // source is the write on `this` of a call to the `SAXParser`
+    // constructor.
+    exists(CallInstruction call |
+      call.getStaticCallTarget() = any(SaxParserClass c).getAConstructor() and
+      node.asInstruction().(WriteSideEffectInstruction).getDestinationAddress() =
+        call.getThisArgument() and
+      encodeXercesFlowState(flowstate, 0, 1) // default configuration
+    )
+    or
+    // source is the result of a call to `createXMLReader`.
+    exists(Call call |
+      call.getTarget() instanceof CreateXmlReader and
+      call = node.asExpr() and
+      encodeXercesFlowState(flowstate, 0, 1) // default configuration
+    )
+    or
+    // source is an `options` argument on a `libxml2` parse call that specifies
+    // at least one unsafe option.
+    //
+    // note: we don't need to track an XML object for `libxml2`, so we don't
+    // really need data flow. Nevertheless we jam it into this configuration,
+    // with matching sources and sinks. This allows results to be presented by
+    // the same query, in a consistent way as other results with flow paths.
+    exists(Libxml2ParseCall call, Expr options |
+      options = call.getOptions() and
+      node.asExpr() = options and
+      flowstate = "libxml2" and
+      exists(Libxml2BadOption opt |
+        globalValueNumber(options).getAnExpr().getValue().toInt().bitAnd(opt.getValue().toInt()) !=
+          0
+      )
     )
   }
 
@@ -201,8 +349,15 @@ class XXEConfiguration extends DataFlow::Configuration {
       call.getTarget() instanceof ParseFunction and
       call.getQualifier() = node.asConvertedExpr()
     ) and
-    flowstate instanceof XercesDOMParserFlowState and
-    not encodeXercesDOMFlowState(flowstate, 1, 1) // safe configuration
+    flowstate instanceof XercesFlowState and
+    not encodeXercesFlowState(flowstate, 1, 1) // safe configuration
+    or
+    // sink is the `options` argument on a `libxml2` parse call.
+    exists(Libxml2ParseCall call, Expr options |
+      options = call.getOptions() and
+      node.asExpr() = options and
+      flowstate = "libxml2"
+    )
   }
 
   override predicate isAdditionalFlowStep(

cpp/ql/src/change-notes/2022-04-28-external-entity-expansion.md

@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* The "XML external entity expansion" (`cpp/external-entity-expansion`) query has been extended to support a broader selection of XML libraries and interfaces.

cpp/ql/src/change-notes/released/0.1.1.md

@@ -1,4 +1,5 @@
----
-category: newQuery
----
+## 0.1.1
+
+### New Queries
+
 * An new query `cpp/external-entity-expansion` has been added. The query detects XML objects that are vulnerable to external entity expansion (XXE) attacks.

cpp/ql/src/codeql-pack.release.yml

@@ -1,2 +1,2 @@
 ---
-lastReleaseVersion: 0.1.0
+lastReleaseVersion: 0.1.1

cpp/ql/src/experimental/Security/CWE/CWE-476/DangerousUseOfExceptionBlocks.cpp

@@ -0,0 +1,48 @@
+...
+try {
+  if (checkValue) throw exception();
+  bufMyData =  new myData*[sizeInt];
+	 
+  } 
+  catch (...) 
+  {
+    for (size_t i = 0; i < sizeInt; i++)
+    {
+    	delete[] bufMyData[i]->buffer; // BAD
+        delete bufMyData[i];
+    }
+...
+try {
+  if (checkValue) throw exception();
+  bufMyData =  new myData*[sizeInt];
+	 
+  } 
+  catch (...) 
+  {
+    for (size_t i = 0; i < sizeInt; i++)
+    {
+      if(bufMyData[i])
+      {
+    	delete[] bufMyData[i]->buffer; // GOOD
+        delete bufMyData[i];
+      }
+    }
+
+...
+  catch (const exception &) {
+	  delete valData;
+	  throw;
+  }
+  catch (...) 
+  {
+    delete valData; // BAD
+...
+  catch (const exception &) {
+	  delete valData;
+    valData = NULL;
+	  throw;
+  }
+  catch (...) 
+  {
+    delete valData; // GOOD  
+...

cpp/ql/src/experimental/Security/CWE/CWE-476/DangerousUseOfExceptionBlocks.qhelp

@@ -0,0 +1,23 @@
+<!DOCTYPE qhelp PUBLIC
+  "-//Semmle//qhelp//EN"
+  "qhelp.dtd">
+<qhelp>
+<overview>
+<p>When releasing memory in a catch block, be sure that the memory was allocated and has not already been released.</p>
+
+</overview>
+
+<example>
+<p>The following example shows erroneous and fixed ways to use exception handling.</p>
+<sample src="DangerousUseOfExceptionBlocks.cpp" />
+
+</example>
+<references>
+
+<li>
+  CERT C Coding Standard:
+  <a href="https://wiki.sei.cmu.edu/confluence/display/c/EXP34-C.+Do+not+dereference+null+pointers">EXP34-C. Do not dereference null pointers</a>.
+</li>
+
+</references>
+</qhelp>

cpp/ql/src/experimental/Security/CWE/CWE-476/DangerousUseOfExceptionBlocks.ql

@@ -0,0 +1,199 @@
+/**
+ * @name Dangerous use of exception blocks.
+ * @description When clearing the data in the catch block, you must be sure that the memory was allocated before the exception.
+ * @kind problem
+ * @id cpp/dangerous-use-of-exception-blocks
+ * @problem.severity warning
+ * @precision medium
+ * @tags correctness
+ *       security
+ *       external/cwe/cwe-476
+ *       external/cwe/cwe-415
+ */
+
+import cpp
+
+/** Holds if `vr` may be released in the `try` block associated with `cb`, or in a `catch` block prior to `cb`. */
+pragma[inline]
+predicate doubleCallDelete(BlockStmt b, CatchAnyBlock cb, Variable vr) {
+  // Search for exceptions after freeing memory.
+  exists(Expr e1 |
+    // `e1` is a delete of `vr`
+    (
+      e1 = vr.getAnAccess().getEnclosingStmt().(ExprStmt).getExpr().(DeleteArrayExpr) or
+      e1 = vr.getAnAccess().getEnclosingStmt().(ExprStmt).getExpr().(DeleteExpr)
+    ) and
+    e1.getEnclosingFunction() = cb.getEnclosingFunction() and
+    // there is no assignment `vr = 0` in the `try` block after `e1`
+    not exists(AssignExpr ae |
+      ae.getLValue().(VariableAccess).getTarget() = vr and
+      ae.getRValue().getValue() = "0" and
+      e1.getASuccessor+() = ae and
+      ae.getEnclosingStmt().getParentStmt*() = b
+    ) and
+    // `e2` is a `throw` (or a function call that may throw) that occurs in the `try` or `catch` block after `e1`
+    exists(Expr e2, ThrowExpr th |
+      (
+        e2 = th or
+        e2 = th.getEnclosingFunction().getACallToThisFunction()
+      ) and
+      e2.getEnclosingStmt().getParentStmt*() = b and
+      e1.getASuccessor+() = e2
+    ) and
+    e1.getEnclosingStmt().getParentStmt*() = b and
+    (
+      // Search for a situation where there is a release in the block of `try`.
+      b = cb.getTryStmt().getStmt()
+      or
+      // Search for a situation when there is a higher catch block that also frees memory.
+      exists(b.(CatchBlock).getParameter())
+    ) and
+    // Exclude the presence of a check in catch block.
+    not exists(IfStmt ifst | ifst.getEnclosingStmt().getParentStmt*() = cb.getAStmt())
+  )
+}
+
+/** Holds if an exception can be thrown before the memory is allocated, and when the exception is handled, an attempt is made to access unallocated memory in the catch block. */
+pragma[inline]
+predicate pointerDereference(CatchAnyBlock cb, Variable vr, Variable vro) {
+  // Search exceptions before allocating memory.
+  exists(Expr e0, Expr e1 |
+    (
+      // `e0` is a `new` expression (or equivalent function call) assigned to `vro`
+      exists(AssignExpr ase |
+        ase = vro.getAnAccess().getEnclosingStmt().(ExprStmt).getExpr() and
+        (
+          e0 = ase.getRValue().(NewOrNewArrayExpr) or
+          e0 = ase.getRValue().(NewOrNewArrayExpr).getEnclosingFunction().getACallToThisFunction()
+        ) and
+        vro = ase.getLValue().(VariableAccess).getTarget()
+      )
+      or
+      // `e0` is a `new` expression (or equivalent function call) assigned to the array element `vro`
+      exists(AssignExpr ase |
+        ase = vro.getAnAccess().(Qualifier).getEnclosingStmt().(ExprStmt).getExpr() and
+        (
+          e0 = ase.getRValue().(NewOrNewArrayExpr) or
+          e0 = ase.getRValue().(NewOrNewArrayExpr).getEnclosingFunction().getACallToThisFunction()
+        ) and
+        not ase.getLValue() instanceof VariableAccess and
+        vro = ase.getLValue().getAPredecessor().(VariableAccess).getTarget()
+      )
+    ) and
+    // `e1` is a `new` expression (or equivalent function call) assigned to `vr`
+    exists(AssignExpr ase |
+      ase = vr.getAnAccess().getEnclosingStmt().(ExprStmt).getExpr() and
+      (
+        e1 = ase.getRValue().(NewOrNewArrayExpr) or
+        e1 = ase.getRValue().(NewOrNewArrayExpr).getEnclosingFunction().getACallToThisFunction()
+      ) and
+      vr = ase.getLValue().(VariableAccess).getTarget()
+    ) and
+    e0.getASuccessor*() = e1 and
+    e0.getEnclosingStmt().getParentStmt*() = cb.getTryStmt().getStmt() and
+    e1.getEnclosingStmt().getParentStmt*() = cb.getTryStmt().getStmt() and
+    // `e2` is a `throw` (or a function call that may throw) that occurs in the `try` block before `e0`
+    exists(Expr e2, ThrowExpr th |
+      (
+        e2 = th or
+        e2 = th.getEnclosingFunction().getACallToThisFunction()
+      ) and
+      e2.getEnclosingStmt().getParentStmt*() = cb.getTryStmt().getStmt() and
+      e2.getASuccessor+() = e0
+    )
+  ) and
+  // We exclude checking the value of a variable or its parent in the catch block.
+  not exists(IfStmt ifst |
+    ifst.getEnclosingStmt().getParentStmt*() = cb.getAStmt() and
+    (
+      ifst.getCondition().getAChild*().(VariableAccess).getTarget() = vr or
+      ifst.getCondition().getAChild*().(VariableAccess).getTarget() = vro
+    )
+  )
+}
+
+/** Holds if `vro` may be released in the `catch`. */
+pragma[inline]
+predicate newThrowDelete(CatchAnyBlock cb, Variable vro) {
+  exists(Expr e0, AssignExpr ase, NewOrNewArrayExpr nae |
+    ase = vro.getAnAccess().getEnclosingStmt().(ExprStmt).getExpr() and
+    nae = ase.getRValue() and
+    not nae.getAChild*().toString() = "nothrow" and
+    (
+      e0 = nae or
+      e0 = nae.getEnclosingFunction().getACallToThisFunction()
+    ) and
+    vro = ase.getLValue().(VariableAccess).getTarget() and
+    e0.getEnclosingStmt().getParentStmt*() = cb.getTryStmt().getStmt() and
+    not exists(AssignExpr ase1 |
+      vro = ase1.getLValue().(VariableAccess).getTarget() and
+      ase1.getRValue().getValue() = "0" and
+      ase1.getASuccessor*() = e0
+    )
+  ) and
+  not exists(Initializer it |
+    vro.getInitializer() = it and
+    it.getExpr().getValue() = "0"
+  ) and
+  not exists(ConstructorFieldInit ci | vro = ci.getTarget())
+}
+
+from CatchAnyBlock cb, string msg
+where
+  exists(Variable vr, Variable vro, Expr exp |
+    exp.getEnclosingStmt().getParentStmt*() = cb and
+    exists(VariableAccess va |
+      (
+        (
+          va = exp.(DeleteArrayExpr).getExpr().getAPredecessor+().(Qualifier) or
+          va = exp.(DeleteArrayExpr).getExpr().getAPredecessor+()
+        ) and
+        vr = exp.(DeleteArrayExpr).getExpr().(VariableAccess).getTarget()
+        or
+        (
+          va = exp.(DeleteExpr).getExpr().getAPredecessor+().(Qualifier) or
+          va = exp.(DeleteExpr).getExpr().getAPredecessor+()
+        ) and
+        vr = exp.(DeleteExpr).getExpr().(VariableAccess).getTarget()
+      ) and
+      va.getEnclosingStmt() = exp.getEnclosingStmt() and
+      vro = va.getTarget() and
+      vr != vro
+    ) and
+    pointerDereference(cb, vr, vro) and
+    msg =
+      "it is possible to dereference a pointer when accessing a " + vr.getName() +
+        ", since it is possible to throw an exception before the memory for the " + vro.getName() +
+        " is allocated"
+  )
+  or
+  exists(Expr exp, Variable vr |
+    (
+      exp.(DeleteExpr).getEnclosingStmt().getParentStmt*() = cb and
+      vr = exp.(DeleteExpr).getExpr().(VariableAccess).getTarget()
+      or
+      exp.(DeleteArrayExpr).getEnclosingStmt().getParentStmt*() = cb and
+      vr = exp.(DeleteArrayExpr).getExpr().(VariableAccess).getTarget()
+    ) and
+    doubleCallDelete(_, cb, vr) and
+    msg =
+      "This allocation may have been released in the try block or a previous catch block." +
+        vr.getName()
+  )
+  or
+  exists(Variable vro, Expr exp |
+    exp.getEnclosingStmt().getParentStmt*() = cb and
+    exists(VariableAccess va |
+      (
+        va = exp.(DeleteArrayExpr).getExpr() or
+        va = exp.(DeleteExpr).getExpr()
+      ) and
+      va.getEnclosingStmt() = exp.getEnclosingStmt() and
+      vro = va.getTarget()
+    ) and
+    newThrowDelete(cb, vro) and
+    msg =
+      "If the allocation in the try block fails, then an unallocated pointer " + vro.getName() +
+        " will be freed in the catch block."
+  )
+select cb, msg

cpp/ql/src/qlpack.yml

@@ -1,5 +1,5 @@
 name: codeql/cpp-queries
-version: 0.1.1-dev
+version: 0.1.2-dev
 groups: 
   - cpp
   - queries

cpp/ql/test/experimental/query-tests/Security/CWE/CWE-020/NoCheckBeforeUnsafePutUser/NoCheckBeforeUnsafePutUser.expected

@@ -0,0 +1 @@
+| test.cpp:14:16:14:16 | p | unsafe_put_user write user-mode pointer $@ without check. | test.cpp:14:16:14:16 | p | p |

cpp/ql/test/experimental/query-tests/Security/CWE/CWE-020/NoCheckBeforeUnsafePutUser/NoCheckBeforeUnsafePutUser.qlref

@@ -0,0 +1 @@
+experimental/Security/CWE/CWE-020/NoCheckBeforeUnsafePutUser.ql

cpp/ql/test/experimental/query-tests/Security/CWE/CWE-020/NoCheckBeforeUnsafePutUser/test.cpp

@@ -0,0 +1,82 @@
+
+typedef unsigned long size_t;
+
+void SYSC_SOMESYSTEMCALL(void *param);
+
+bool user_access_begin_impl(const void *where, size_t sz);
+void user_access_end_impl();
+#define user_access_begin(where, sz) user_access_begin_impl(where, sz)
+#define user_access_end() user_access_end_impl()
+
+void unsafe_put_user_impl(int what, const void *where, size_t sz);
+#define unsafe_put_user(what, where) unsafe_put_user_impl( (what), (where), sizeof(*(where)) )
+
+void test1(int p)
+{
+	SYSC_SOMESYSTEMCALL(&p);
+
+	unsafe_put_user(123, &p); // BAD
+}
+
+void test2(int p)
+{
+	SYSC_SOMESYSTEMCALL(&p);
+
+	if (user_access_begin(&p, sizeof(p)))
+	{
+		unsafe_put_user(123, &p); // GOOD
+
+		user_access_end();
+	}
+}
+
+void test3()
+{
+	int v;
+
+	SYSC_SOMESYSTEMCALL(&v);
+
+	unsafe_put_user(123, &v); // BAD [NOT DETECTED]
+}
+
+void test4()
+{
+	int v;
+
+	SYSC_SOMESYSTEMCALL(&v);
+
+	if (user_access_begin(&v, sizeof(v)))
+	{
+		unsafe_put_user(123, &v); // GOOD
+
+		user_access_end();
+	}
+}
+
+struct data
+{
+	int x;
+};
+
+void test5()
+{
+	data myData;
+
+	SYSC_SOMESYSTEMCALL(&myData);
+
+	unsafe_put_user(123, &(myData.x)); // BAD [NOT DETECTED]
+}
+
+void test6()
+{
+	data myData;
+
+	SYSC_SOMESYSTEMCALL(&myData);
+
+	if (user_access_begin(&myData, sizeof(myData)))
+	{
+		unsafe_put_user(123, &(myData.x)); // GOOD
+
+		user_access_end();
+	}
+}

cpp/ql/test/experimental/query-tests/Security/CWE/CWE-476/semmle/tests/DangerousUseOfExceptionBlocks.expected

@@ -0,0 +1,8 @@
+| test.cpp:63:3:71:3 | { ... } | If the allocation in the try block fails, then an unallocated pointer bufMyData will be freed in the catch block. |
+| test.cpp:63:3:71:3 | { ... } | If the allocation in the try block fails, then an unallocated pointer buffer will be freed in the catch block. |
+| test.cpp:63:3:71:3 | { ... } | it is possible to dereference a pointer when accessing a buffer, since it is possible to throw an exception before the memory for the bufMyData is allocated |
+| test.cpp:91:3:100:3 | { ... } | If the allocation in the try block fails, then an unallocated pointer buffer will be freed in the catch block. |
+| test.cpp:120:3:128:3 | { ... } | If the allocation in the try block fails, then an unallocated pointer buffer will be freed in the catch block. |
+| test.cpp:143:3:151:3 | { ... } | If the allocation in the try block fails, then an unallocated pointer buffer will be freed in the catch block. |
+| test.cpp:181:3:183:3 | { ... } | This allocation may have been released in the try block or a previous catch block.valData |
+| test.cpp:219:3:221:3 | { ... } | This allocation may have been released in the try block or a previous catch block.valData |

cpp/ql/test/experimental/query-tests/Security/CWE/CWE-476/semmle/tests/DangerousUseOfExceptionBlocks.qlref

@@ -0,0 +1 @@
+experimental/Security/CWE/CWE-476/DangerousUseOfExceptionBlocks.ql

cpp/ql/test/experimental/query-tests/Security/CWE/CWE-476/semmle/tests/test.cpp

@@ -0,0 +1,255 @@
+#define NULL ((void*)0)
+typedef unsigned long size_t;
+namespace std {
+  enum class align_val_t : size_t {};
+}
+
+class exception {};
+
+void cleanFunction();
+
+void* operator new(size_t, float);
+void* operator new[](size_t, float);
+void* operator new(size_t, std::align_val_t, float);
+void* operator new[](size_t, std::align_val_t, float);
+void operator delete(void*, float);
+void operator delete[](void*, float);
+void operator delete(void*, std::align_val_t, float);
+void operator delete[](void*, std::align_val_t, float);
+
+struct myData
+{
+    int		sizeInt;
+    char*	buffer;
+};
+
+struct myGlobalData
+{
+    int		sizeInt;
+    myData**	bufMyData;
+};
+
+void allocData(myData ** bufMyData) {
+    for (size_t i = 0; i < 10; i++)
+    {
+        bufMyData[i] = new myData;
+	bufMyData[i]->sizeInt = 10;
+	bufMyData[i]->buffer = new char[10];
+    }
+}
+
+
+void throwFunction(int a) {
+	if (a == 5)  throw "my exception!";
+}
+void throwFunction2(int a) {
+	if (a == 5) throw exception();
+}
+void funcWork1b() {
+  int a;
+  myData **bufMyData;
+
+  try { 
+  	cleanFunction();
+	throwFunction(a);
+
+        bufMyData =  new myData*[10];
+	cleanFunction();
+	allocData(bufMyData);
+	cleanFunction();
+	 
+  } 
+  catch (...) 
+  {
+    for (size_t i = 0; i < 10; i++)
+    {
+    	delete[] bufMyData[i]->buffer; // BAD
+        delete bufMyData[i];
+    }
+    delete [] bufMyData;
+
+  }
+}
+
+void funcWork1() {
+  int a;
+  int i;
+  myData **bufMyData;
+
+  bufMyData =  new myData*[10];
+  for (i = 0; i < 10; i++)
+    bufMyData[i] = 0;
+  try { 
+  	cleanFunction();
+	throwFunction(a);
+	cleanFunction();
+	allocData(bufMyData);
+	cleanFunction();
+	 
+  } 
+  catch (...) 
+  {
+    for (size_t i = 0; i < 10; i++)
+    {
+	if (bufMyData[i]) 
+       	    delete[] bufMyData[i]->buffer; // BAD
+        delete bufMyData[i];
+    }
+    delete [] bufMyData;
+
+  }
+}
+
+void funcWork2() {
+  int a;
+  myData **bufMyData;
+
+  bufMyData =  new myData*[10];
+  try { 
+ 	do {
+		cleanFunction();
+		allocData(bufMyData);
+		cleanFunction();
+		throwFunction(a);
+
+	}
+	while(0);
+	 
+  } 
+  catch (...) 
+  {
+    for (size_t i = 0; i < 10; i++)
+    {
+    	delete[] bufMyData[i]->buffer; // BAD
+        delete bufMyData[i];
+    }
+    delete [] bufMyData;
+
+  }
+}
+void funcWork3() {
+  int a;
+  myData **bufMyData;
+
+  bufMyData =  new myData*[10];
+  try { 
+	cleanFunction();
+	allocData(bufMyData);
+	cleanFunction();
+	throwFunction(a);
+ 
+  } 
+  catch (...) 
+  {
+    for (size_t i = 0; i < 10; i++)
+    {
+    	delete[] bufMyData[i]->buffer; // BAD
+        delete bufMyData[i];
+    }
+    delete [] bufMyData;
+
+  }
+}
+
+
+void funcWork4() {
+  int a;
+  myGlobalData *valData = 0;
+  try { 
+	valData = new myGlobalData;
+	cleanFunction();
+	delete valData;
+	valData = 0;
+	throwFunction(a);	 
+  } 
+  catch (...) 
+  {
+    delete valData; // GOOD
+  }
+}
+
+void funcWork4b() {
+  int a;
+  myGlobalData *valData = 0;
+  try { 
+	valData = new myGlobalData;
+	cleanFunction();
+	delete valData;
+	throwFunction(a);	 
+  } 
+  catch (...) 
+  {
+    delete valData; // BAD
+  }
+}
+void funcWork5() {
+  int a;
+  myGlobalData *valData = 0;
+  try { 
+	valData = new myGlobalData;
+	cleanFunction();
+	delete valData;
+	valData = 0;
+	throwFunction2(a);	 
+  } 
+  catch (const exception &) {
+	delete valData;
+	valData = 0;
+	throw;
+  }
+  catch (...) 
+  {
+        delete valData; // GOOD
+  }
+}
+
+void funcWork5b() {
+  int a;
+  myGlobalData *valData = 0;
+  try { 
+	valData = new myGlobalData;
+	cleanFunction();
+	throwFunction2(a);	 
+  } 
+  catch (const exception &) {
+	delete valData;
+	throw;
+  }
+  catch (...) 
+  {
+        delete valData; // BAD
+  }
+}
+void funcWork6() {
+  int a;
+  int flagB = 0;
+  myGlobalData *valData = 0;
+  try { 
+	valData = new myGlobalData;
+	cleanFunction();
+	throwFunction2(a);	 
+  } 
+  catch (const exception &) {
+	delete valData;
+	flagB = 1;
+	throw;
+  }
+  catch (...) 
+  {
+	if(flagB == 0)
+        delete valData; // GOOD
+  }
+}
+
+void runnerFunc()
+{
+  funcWork1();
+  funcWork1b();
+  funcWork2();
+  funcWork3();
+  funcWork4();
+  funcWork4b();
+  funcWork5();
+  funcWork5b();
+  funcWork6();
+}

cpp/ql/test/library-tests/string_analysis/StringAnalysis.ql

@@ -5,7 +5,7 @@
 
 import cpp
 
-from AnalysedString s, string str
+from AnalyzedString s, string str
 where
   if s.(StringLiteral).getUnspecifiedType().(DerivedType).getBaseType() instanceof Wchar_t
   then str = "[?]"

cpp/ql/test/query-tests/Security/CWE/CWE-611/XXE.expected

@@ -1,80 +1,106 @@
 edges
-| tests.cpp:33:23:33:43 | XercesDOMParser output argument | tests.cpp:35:2:35:2 | p |
-| tests.cpp:46:23:46:43 | XercesDOMParser output argument | tests.cpp:49:2:49:2 | p |
-| tests.cpp:53:19:53:19 | VariableAddress [post update] | tests.cpp:55:2:55:2 | p |
-| tests.cpp:53:23:53:43 | XercesDOMParser output argument | tests.cpp:53:19:53:19 | VariableAddress [post update] |
+| tests2.cpp:20:17:20:31 | SAXParser output argument | tests2.cpp:22:2:22:2 | p |
+| tests2.cpp:33:17:33:31 | SAXParser output argument | tests2.cpp:37:2:37:2 | p |
+| tests3.cpp:23:21:23:53 | call to createXMLReader | tests3.cpp:25:2:25:2 | p |
+| tests3.cpp:60:21:60:53 | call to createXMLReader | tests3.cpp:63:2:63:2 | p |
+| tests3.cpp:67:21:67:53 | call to createXMLReader | tests3.cpp:70:2:70:2 | p |
+| tests.cpp:15:23:15:43 | XercesDOMParser output argument | tests.cpp:17:2:17:2 | p |
+| tests.cpp:28:23:28:43 | XercesDOMParser output argument | tests.cpp:31:2:31:2 | p |
+| tests.cpp:35:19:35:19 | VariableAddress [post update] | tests.cpp:37:2:37:2 | p |
+| tests.cpp:35:23:35:43 | XercesDOMParser output argument | tests.cpp:35:19:35:19 | VariableAddress [post update] |
+| tests.cpp:37:2:37:2 | p | tests.cpp:38:2:38:2 | p |
+| tests.cpp:38:2:38:2 | p | tests.cpp:39:2:39:2 | p |
+| tests.cpp:51:19:51:19 | VariableAddress [post update] | tests.cpp:53:2:53:2 | p |
+| tests.cpp:51:23:51:43 | XercesDOMParser output argument | tests.cpp:51:19:51:19 | VariableAddress [post update] |
+| tests.cpp:53:2:53:2 | p | tests.cpp:54:2:54:2 | p |
+| tests.cpp:54:2:54:2 | p | tests.cpp:55:2:55:2 | p |
+| tests.cpp:55:2:55:2 | p | tests.cpp:56:2:56:2 | p |
 | tests.cpp:55:2:55:2 | p | tests.cpp:56:2:56:2 | p |
 | tests.cpp:56:2:56:2 | p | tests.cpp:57:2:57:2 | p |
-| tests.cpp:69:19:69:19 | VariableAddress [post update] | tests.cpp:71:2:71:2 | p |
-| tests.cpp:69:23:69:43 | XercesDOMParser output argument | tests.cpp:69:19:69:19 | VariableAddress [post update] |
-| tests.cpp:71:2:71:2 | p | tests.cpp:72:2:72:2 | p |
-| tests.cpp:72:2:72:2 | p | tests.cpp:73:2:73:2 | p |
-| tests.cpp:73:2:73:2 | p | tests.cpp:74:2:74:2 | p |
-| tests.cpp:73:2:73:2 | p | tests.cpp:74:2:74:2 | p |
-| tests.cpp:74:2:74:2 | p | tests.cpp:75:2:75:2 | p |
-| tests.cpp:75:2:75:2 | p | tests.cpp:76:2:76:2 | p |
-| tests.cpp:76:2:76:2 | p | tests.cpp:77:2:77:2 | p |
-| tests.cpp:77:2:77:2 | p | tests.cpp:78:2:78:2 | p |
-| tests.cpp:84:23:84:43 | XercesDOMParser output argument | tests.cpp:87:2:87:2 | p |
-| tests.cpp:91:23:91:43 | XercesDOMParser output argument | tests.cpp:98:2:98:2 | p |
-| tests.cpp:103:24:103:44 | XercesDOMParser output argument | tests.cpp:106:3:106:3 | q |
-| tests.cpp:118:24:118:44 | XercesDOMParser output argument | tests.cpp:122:3:122:3 | q |
-| tests.cpp:130:39:130:39 | p | tests.cpp:131:2:131:2 | p |
-| tests.cpp:134:39:134:39 | p | tests.cpp:135:2:135:2 | p |
-| tests.cpp:140:23:140:43 | XercesDOMParser output argument | tests.cpp:144:18:144:18 | q |
-| tests.cpp:140:23:140:43 | XercesDOMParser output argument | tests.cpp:146:18:146:18 | q |
-| tests.cpp:144:18:144:18 | q | tests.cpp:130:39:130:39 | p |
-| tests.cpp:146:18:146:18 | q | tests.cpp:134:39:134:39 | p |
-| tests.cpp:150:19:150:32 | call to createLSParser | tests.cpp:152:2:152:2 | p |
+| tests.cpp:57:2:57:2 | p | tests.cpp:58:2:58:2 | p |
+| tests.cpp:58:2:58:2 | p | tests.cpp:59:2:59:2 | p |
+| tests.cpp:59:2:59:2 | p | tests.cpp:60:2:60:2 | p |
+| tests.cpp:66:23:66:43 | XercesDOMParser output argument | tests.cpp:69:2:69:2 | p |
+| tests.cpp:73:23:73:43 | XercesDOMParser output argument | tests.cpp:80:2:80:2 | p |
+| tests.cpp:85:24:85:44 | XercesDOMParser output argument | tests.cpp:88:3:88:3 | q |
+| tests.cpp:100:24:100:44 | XercesDOMParser output argument | tests.cpp:104:3:104:3 | q |
+| tests.cpp:112:39:112:39 | p | tests.cpp:113:2:113:2 | p |
+| tests.cpp:116:39:116:39 | p | tests.cpp:117:2:117:2 | p |
+| tests.cpp:122:23:122:43 | XercesDOMParser output argument | tests.cpp:126:18:126:18 | q |
+| tests.cpp:122:23:122:43 | XercesDOMParser output argument | tests.cpp:128:18:128:18 | q |
+| tests.cpp:126:18:126:18 | q | tests.cpp:112:39:112:39 | p |
+| tests.cpp:128:18:128:18 | q | tests.cpp:116:39:116:39 | p |
 nodes
-| tests.cpp:33:23:33:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
-| tests.cpp:35:2:35:2 | p | semmle.label | p |
-| tests.cpp:46:23:46:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
-| tests.cpp:49:2:49:2 | p | semmle.label | p |
-| tests.cpp:53:19:53:19 | VariableAddress [post update] | semmle.label | VariableAddress [post update] |
-| tests.cpp:53:23:53:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests2.cpp:20:17:20:31 | SAXParser output argument | semmle.label | SAXParser output argument |
+| tests2.cpp:22:2:22:2 | p | semmle.label | p |
+| tests2.cpp:33:17:33:31 | SAXParser output argument | semmle.label | SAXParser output argument |
+| tests2.cpp:37:2:37:2 | p | semmle.label | p |
+| tests3.cpp:23:21:23:53 | call to createXMLReader | semmle.label | call to createXMLReader |
+| tests3.cpp:25:2:25:2 | p | semmle.label | p |
+| tests3.cpp:60:21:60:53 | call to createXMLReader | semmle.label | call to createXMLReader |
+| tests3.cpp:63:2:63:2 | p | semmle.label | p |
+| tests3.cpp:67:21:67:53 | call to createXMLReader | semmle.label | call to createXMLReader |
+| tests3.cpp:70:2:70:2 | p | semmle.label | p |
+| tests4.cpp:26:34:26:48 | (int)... | semmle.label | (int)... |
+| tests4.cpp:36:34:36:50 | (int)... | semmle.label | (int)... |
+| tests4.cpp:46:34:46:68 | ... \| ... | semmle.label | ... \| ... |
+| tests4.cpp:77:34:77:38 | flags | semmle.label | flags |
+| tests4.cpp:130:39:130:55 | (int)... | semmle.label | (int)... |
+| tests.cpp:15:23:15:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:17:2:17:2 | p | semmle.label | p |
+| tests.cpp:28:23:28:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:31:2:31:2 | p | semmle.label | p |
+| tests.cpp:35:19:35:19 | VariableAddress [post update] | semmle.label | VariableAddress [post update] |
+| tests.cpp:35:23:35:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:37:2:37:2 | p | semmle.label | p |
+| tests.cpp:38:2:38:2 | p | semmle.label | p |
+| tests.cpp:39:2:39:2 | p | semmle.label | p |
+| tests.cpp:51:19:51:19 | VariableAddress [post update] | semmle.label | VariableAddress [post update] |
+| tests.cpp:51:23:51:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:53:2:53:2 | p | semmle.label | p |
+| tests.cpp:54:2:54:2 | p | semmle.label | p |
 | tests.cpp:55:2:55:2 | p | semmle.label | p |
 | tests.cpp:56:2:56:2 | p | semmle.label | p |
+| tests.cpp:56:2:56:2 | p | semmle.label | p |
 | tests.cpp:57:2:57:2 | p | semmle.label | p |
-| tests.cpp:69:19:69:19 | VariableAddress [post update] | semmle.label | VariableAddress [post update] |
-| tests.cpp:69:23:69:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
-| tests.cpp:71:2:71:2 | p | semmle.label | p |
-| tests.cpp:72:2:72:2 | p | semmle.label | p |
-| tests.cpp:73:2:73:2 | p | semmle.label | p |
-| tests.cpp:74:2:74:2 | p | semmle.label | p |
-| tests.cpp:74:2:74:2 | p | semmle.label | p |
-| tests.cpp:75:2:75:2 | p | semmle.label | p |
-| tests.cpp:76:2:76:2 | p | semmle.label | p |
-| tests.cpp:77:2:77:2 | p | semmle.label | p |
-| tests.cpp:78:2:78:2 | p | semmle.label | p |
-| tests.cpp:84:23:84:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
-| tests.cpp:87:2:87:2 | p | semmle.label | p |
-| tests.cpp:91:23:91:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
-| tests.cpp:98:2:98:2 | p | semmle.label | p |
-| tests.cpp:103:24:103:44 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
-| tests.cpp:106:3:106:3 | q | semmle.label | q |
-| tests.cpp:118:24:118:44 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
-| tests.cpp:122:3:122:3 | q | semmle.label | q |
-| tests.cpp:130:39:130:39 | p | semmle.label | p |
-| tests.cpp:131:2:131:2 | p | semmle.label | p |
-| tests.cpp:134:39:134:39 | p | semmle.label | p |
-| tests.cpp:135:2:135:2 | p | semmle.label | p |
-| tests.cpp:140:23:140:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
-| tests.cpp:144:18:144:18 | q | semmle.label | q |
-| tests.cpp:146:18:146:18 | q | semmle.label | q |
-| tests.cpp:150:19:150:32 | call to createLSParser | semmle.label | call to createLSParser |
-| tests.cpp:152:2:152:2 | p | semmle.label | p |
+| tests.cpp:58:2:58:2 | p | semmle.label | p |
+| tests.cpp:59:2:59:2 | p | semmle.label | p |
+| tests.cpp:60:2:60:2 | p | semmle.label | p |
+| tests.cpp:66:23:66:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:69:2:69:2 | p | semmle.label | p |
+| tests.cpp:73:23:73:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:80:2:80:2 | p | semmle.label | p |
+| tests.cpp:85:24:85:44 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:88:3:88:3 | q | semmle.label | q |
+| tests.cpp:100:24:100:44 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:104:3:104:3 | q | semmle.label | q |
+| tests.cpp:112:39:112:39 | p | semmle.label | p |
+| tests.cpp:113:2:113:2 | p | semmle.label | p |
+| tests.cpp:116:39:116:39 | p | semmle.label | p |
+| tests.cpp:117:2:117:2 | p | semmle.label | p |
+| tests.cpp:122:23:122:43 | XercesDOMParser output argument | semmle.label | XercesDOMParser output argument |
+| tests.cpp:126:18:126:18 | q | semmle.label | q |
+| tests.cpp:128:18:128:18 | q | semmle.label | q |
 subpaths
 #select
-| tests.cpp:35:2:35:2 | p | tests.cpp:33:23:33:43 | XercesDOMParser output argument | tests.cpp:35:2:35:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:33:23:33:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:49:2:49:2 | p | tests.cpp:46:23:46:43 | XercesDOMParser output argument | tests.cpp:49:2:49:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:46:23:46:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:57:2:57:2 | p | tests.cpp:53:23:53:43 | XercesDOMParser output argument | tests.cpp:57:2:57:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:53:23:53:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:74:2:74:2 | p | tests.cpp:69:23:69:43 | XercesDOMParser output argument | tests.cpp:74:2:74:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:69:23:69:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:78:2:78:2 | p | tests.cpp:69:23:69:43 | XercesDOMParser output argument | tests.cpp:78:2:78:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:69:23:69:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:87:2:87:2 | p | tests.cpp:84:23:84:43 | XercesDOMParser output argument | tests.cpp:87:2:87:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:84:23:84:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:98:2:98:2 | p | tests.cpp:91:23:91:43 | XercesDOMParser output argument | tests.cpp:98:2:98:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:91:23:91:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:106:3:106:3 | q | tests.cpp:103:24:103:44 | XercesDOMParser output argument | tests.cpp:106:3:106:3 | q | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:103:24:103:44 | XercesDOMParser output argument | XML parser |
-| tests.cpp:122:3:122:3 | q | tests.cpp:118:24:118:44 | XercesDOMParser output argument | tests.cpp:122:3:122:3 | q | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:118:24:118:44 | XercesDOMParser output argument | XML parser |
-| tests.cpp:131:2:131:2 | p | tests.cpp:140:23:140:43 | XercesDOMParser output argument | tests.cpp:131:2:131:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:140:23:140:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:135:2:135:2 | p | tests.cpp:140:23:140:43 | XercesDOMParser output argument | tests.cpp:135:2:135:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:140:23:140:43 | XercesDOMParser output argument | XML parser |
-| tests.cpp:152:2:152:2 | p | tests.cpp:150:19:150:32 | call to createLSParser | tests.cpp:152:2:152:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:150:19:150:32 | call to createLSParser | XML parser |
+| tests2.cpp:22:2:22:2 | p | tests2.cpp:20:17:20:31 | SAXParser output argument | tests2.cpp:22:2:22:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests2.cpp:20:17:20:31 | SAXParser output argument | XML parser |
+| tests2.cpp:37:2:37:2 | p | tests2.cpp:33:17:33:31 | SAXParser output argument | tests2.cpp:37:2:37:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests2.cpp:33:17:33:31 | SAXParser output argument | XML parser |
+| tests3.cpp:25:2:25:2 | p | tests3.cpp:23:21:23:53 | call to createXMLReader | tests3.cpp:25:2:25:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests3.cpp:23:21:23:53 | call to createXMLReader | XML parser |
+| tests3.cpp:63:2:63:2 | p | tests3.cpp:60:21:60:53 | call to createXMLReader | tests3.cpp:63:2:63:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests3.cpp:60:21:60:53 | call to createXMLReader | XML parser |
+| tests3.cpp:70:2:70:2 | p | tests3.cpp:67:21:67:53 | call to createXMLReader | tests3.cpp:70:2:70:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests3.cpp:67:21:67:53 | call to createXMLReader | XML parser |
+| tests4.cpp:26:34:26:48 | (int)... | tests4.cpp:26:34:26:48 | (int)... | tests4.cpp:26:34:26:48 | (int)... | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests4.cpp:26:34:26:48 | (int)... | XML parser |
+| tests4.cpp:36:34:36:50 | (int)... | tests4.cpp:36:34:36:50 | (int)... | tests4.cpp:36:34:36:50 | (int)... | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests4.cpp:36:34:36:50 | (int)... | XML parser |
+| tests4.cpp:46:34:46:68 | ... \| ... | tests4.cpp:46:34:46:68 | ... \| ... | tests4.cpp:46:34:46:68 | ... \| ... | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests4.cpp:46:34:46:68 | ... \| ... | XML parser |
+| tests4.cpp:77:34:77:38 | flags | tests4.cpp:77:34:77:38 | flags | tests4.cpp:77:34:77:38 | flags | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests4.cpp:77:34:77:38 | flags | XML parser |
+| tests4.cpp:130:39:130:55 | (int)... | tests4.cpp:130:39:130:55 | (int)... | tests4.cpp:130:39:130:55 | (int)... | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests4.cpp:130:39:130:55 | (int)... | XML parser |
+| tests.cpp:17:2:17:2 | p | tests.cpp:15:23:15:43 | XercesDOMParser output argument | tests.cpp:17:2:17:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:15:23:15:43 | XercesDOMParser output argument | XML parser |
+| tests.cpp:31:2:31:2 | p | tests.cpp:28:23:28:43 | XercesDOMParser output argument | tests.cpp:31:2:31:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:28:23:28:43 | XercesDOMParser output argument | XML parser |
+| tests.cpp:39:2:39:2 | p | tests.cpp:35:23:35:43 | XercesDOMParser output argument | tests.cpp:39:2:39:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:35:23:35:43 | XercesDOMParser output argument | XML parser |
+| tests.cpp:56:2:56:2 | p | tests.cpp:51:23:51:43 | XercesDOMParser output argument | tests.cpp:56:2:56:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:51:23:51:43 | XercesDOMParser output argument | XML parser |
+| tests.cpp:60:2:60:2 | p | tests.cpp:51:23:51:43 | XercesDOMParser output argument | tests.cpp:60:2:60:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:51:23:51:43 | XercesDOMParser output argument | XML parser |
+| tests.cpp:69:2:69:2 | p | tests.cpp:66:23:66:43 | XercesDOMParser output argument | tests.cpp:69:2:69:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:66:23:66:43 | XercesDOMParser output argument | XML parser |
+| tests.cpp:80:2:80:2 | p | tests.cpp:73:23:73:43 | XercesDOMParser output argument | tests.cpp:80:2:80:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:73:23:73:43 | XercesDOMParser output argument | XML parser |
+| tests.cpp:88:3:88:3 | q | tests.cpp:85:24:85:44 | XercesDOMParser output argument | tests.cpp:88:3:88:3 | q | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:85:24:85:44 | XercesDOMParser output argument | XML parser |
+| tests.cpp:104:3:104:3 | q | tests.cpp:100:24:100:44 | XercesDOMParser output argument | tests.cpp:104:3:104:3 | q | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:100:24:100:44 | XercesDOMParser output argument | XML parser |
+| tests.cpp:113:2:113:2 | p | tests.cpp:122:23:122:43 | XercesDOMParser output argument | tests.cpp:113:2:113:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:122:23:122:43 | XercesDOMParser output argument | XML parser |
+| tests.cpp:117:2:117:2 | p | tests.cpp:122:23:122:43 | XercesDOMParser output argument | tests.cpp:117:2:117:2 | p | This $@ is not configured to prevent an XML external entity (XXE) attack. | tests.cpp:122:23:122:43 | XercesDOMParser output argument | XML parser |

cpp/ql/test/query-tests/Security/CWE/CWE-611/tests.cpp

@@ -1,32 +1,14 @@
-// test cases for rule CWE-611
+// test cases for rule CWE-611 (XercesDOMParser)
 
 #include "tests.h"
 
 // ---
 
-class SecurityManager;
-class InputSource;
-
-class AbstractDOMParser {
-public:
-	AbstractDOMParser();
-
-	void setDisableDefaultEntityResolution(bool); // default is false
-	void setCreateEntityReferenceNodes(bool); // default is true
-	void setSecurityManager(SecurityManager *const manager);
-	void parse(const InputSource &data);
-};
-
 class XercesDOMParser: public AbstractDOMParser {
 public:
 	XercesDOMParser();
 };
 
-class DOMLSParser : public AbstractDOMParser {
-};
-
-DOMLSParser *createLSParser();
-
 // ---
 
 void test1(InputSource &data) {
@@ -145,26 +127,3 @@ void test10(InputSource &data) {
 	test10_doParseC(p, data);
 	test10_doParseC(q, data);
 }
-
-void test11(InputSource &data) {
-	DOMLSParser *p = createLSParser();
-
-	p->parse(data); // BAD (parser not correctly configured)
-}
-
-void test12(InputSource &data) {
-	DOMLSParser *p = createLSParser();
-
-	p->setDisableDefaultEntityResolution(true);
-	p->parse(data); // GOOD
-}
-
-DOMLSParser *g_p1 = createLSParser();
-DOMLSParser *g_p2 = createLSParser();
-InputSource *g_data;
-
-void test13() {
-	g_p1->setDisableDefaultEntityResolution(true);
-	g_p1->parse(*g_data); // GOOD
-	g_p2->parse(*g_data); // BAD (parser not correctly configured) [NOT DETECTED]
-}

cpp/ql/test/query-tests/Security/CWE/CWE-611/tests.h

@@ -1,2 +1,26 @@
-// library functions for rule CWE-611
+// library/common functions for rule CWE-611
+
+#define NULL (0)
+
+class SecurityManager;
+class InputSource;
+
+class AbstractDOMParser {
+public:
+	AbstractDOMParser();
+
+	void setDisableDefaultEntityResolution(bool); // default is false
+	void setCreateEntityReferenceNodes(bool); // default is true
+	void setSecurityManager(SecurityManager *const manager);
+	void parse(const InputSource &data);
+};
+
+typedef unsigned int XMLCh;
+
+class XMLUni
+{
+public:
+	static const XMLCh fgXercesDisableDefaultEntityResolution[];
+	static const XMLCh fgXercesHarmlessOption[];
+};
 

cpp/ql/test/query-tests/Security/CWE/CWE-611/tests2.cpp

@@ -0,0 +1,46 @@
+// test cases for rule CWE-611 (SAXParser)
+
+#include "tests.h"
+
+// ---
+
+class SAXParser
+{
+public:
+	SAXParser();
+
+	void setDisableDefaultEntityResolution(bool); // default is false
+	void setSecurityManager(SecurityManager *const manager);
+	void parse(const InputSource &data);
+};
+
+// ---
+
+void test2_1(InputSource &data) {
+	SAXParser *p = new SAXParser();
+
+	p->parse(data); // BAD (parser not correctly configured)
+}
+
+void test2_2(InputSource &data) {
+	SAXParser *p = new SAXParser();
+
+	p->setDisableDefaultEntityResolution(true);
+	p->parse(data); // GOOD
+}
+
+void test2_3(InputSource &data) {
+	SAXParser *p = new SAXParser();
+	bool v = false;
+
+	p->setDisableDefaultEntityResolution(v);
+	p->parse(data); // BAD (parser not correctly configured)
+}
+
+void test2_4(InputSource &data) {
+	SAXParser *p = new SAXParser();
+	bool v = true;
+
+	p->setDisableDefaultEntityResolution(v);
+	p->parse(data); // GOOD
+}

cpp/ql/test/query-tests/Security/CWE/CWE-611/tests3.cpp

@@ -0,0 +1,82 @@
+// test cases for rule CWE-611 (SAX2XMLReader)
+
+#include "tests.h"
+
+// ---
+
+class SAX2XMLReader
+{
+public:
+	void setFeature(const XMLCh *feature, bool value);
+	void parse(const InputSource &data);
+};
+
+class XMLReaderFactory
+{
+public:
+	static SAX2XMLReader *createXMLReader();
+};
+
+// ---
+
+void test3_1(InputSource &data) {
+	SAX2XMLReader *p = XMLReaderFactory::createXMLReader();
+
+	p->parse(data); // BAD (parser not correctly configured) [NOT DETECTED]
+}
+
+void test3_2(InputSource &data) {
+	SAX2XMLReader *p = XMLReaderFactory::createXMLReader();
+
+	p->setFeature(XMLUni::fgXercesDisableDefaultEntityResolution, true);
+	p->parse(data); // GOOD
+}
+
+SAX2XMLReader *p_3_3 = XMLReaderFactory::createXMLReader();
+
+void test3_3(InputSource &data) {
+	p_3_3->parse(data); // BAD (parser not correctly configured) [NOT DETECTED]
+}
+
+SAX2XMLReader *p_3_4 = XMLReaderFactory::createXMLReader();
+
+void test3_4(InputSource &data) {
+	p_3_4->setFeature(XMLUni::fgXercesDisableDefaultEntityResolution, true);
+	p_3_4->parse(data); // GOOD
+}
+
+SAX2XMLReader *p_3_5 = XMLReaderFactory::createXMLReader();
+
+void test3_5_init() {
+	p_3_5->setFeature(XMLUni::fgXercesDisableDefaultEntityResolution, true);
+}
+
+void test3_5(InputSource &data) {
+	test3_5_init();
+	p_3_5->parse(data); // GOOD
+}
+
+void test3_6(InputSource &data) {
+	SAX2XMLReader *p = XMLReaderFactory::createXMLReader();
+
+	p->setFeature(XMLUni::fgXercesDisableDefaultEntityResolution, false);
+	p->parse(data); // BAD (parser not correctly configured)
+}
+
+void test3_7(InputSource &data) {
+	SAX2XMLReader *p = XMLReaderFactory::createXMLReader();
+
+	p->setFeature(XMLUni::fgXercesHarmlessOption, true);
+	p->parse(data); // BAD (parser not correctly configured)
+}
+
+void test3_8(InputSource &data) {
+	SAX2XMLReader *p = XMLReaderFactory::createXMLReader();
+	const XMLCh *feature = XMLUni::fgXercesDisableDefaultEntityResolution;
+
+	p->setFeature(feature, true);
+	p->parse(data); // GOOD
+}
+
+
+

cpp/ql/test/query-tests/Security/CWE/CWE-611/tests4.cpp

@@ -0,0 +1,135 @@
+// test cases for rule CWE-611 (libxml2)
+
+#include "tests.h"
+
+// ---
+
+enum xmlParserOption
+{
+	XML_PARSE_NOENT = 2,
+	XML_PARSE_DTDLOAD = 4,
+	XML_PARSE_OPTION_HARMLESS = 8
+};
+
+class xmlDoc;
+
+xmlDoc *xmlReadFile(const char *fileName, const char *encoding, int flags);
+xmlDoc *xmlReadMemory(const char *ptr, int sz, const char *url, const char *encoding, int flags);
+
+void xmlFreeDoc(xmlDoc *ptr);
+
+// ---
+
+void test4_1(const char *fileName) {
+	xmlDoc *p;
+
+	p = xmlReadFile(fileName, NULL, XML_PARSE_NOENT); // BAD (parser not correctly configured)
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_2(const char *fileName) {
+	xmlDoc *p;
+
+	p = xmlReadFile(fileName, NULL, XML_PARSE_DTDLOAD); // BAD (parser not correctly configured)
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_3(const char *fileName) {
+	xmlDoc *p;
+
+	p = xmlReadFile(fileName, NULL, XML_PARSE_NOENT | XML_PARSE_DTDLOAD); // BAD (parser not correctly configured)
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_4(const char *fileName) {
+	xmlDoc *p;
+
+	p = xmlReadFile(fileName, NULL, 0); // GOOD
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_5(const char *fileName) {
+	xmlDoc *p;
+
+	p = xmlReadFile(fileName, NULL, XML_PARSE_OPTION_HARMLESS); // GOOD
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_6(const char *fileName) {
+	xmlDoc *p;
+	int flags = XML_PARSE_NOENT;
+
+	p = xmlReadFile(fileName, NULL, flags); // BAD (parser not correctly configured)
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_7(const char *fileName) {
+	xmlDoc *p;
+	int flags = 0;
+
+	p = xmlReadFile(fileName, NULL, flags); // GOOD
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_8(const char *fileName) {
+	xmlDoc *p;
+	int flags = XML_PARSE_OPTION_HARMLESS;
+
+	p = xmlReadFile(fileName, NULL, flags | XML_PARSE_NOENT); // BAD (parser not correctly configured) [NOT DETECTED]
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_9(const char *fileName) {
+	xmlDoc *p;
+	int flags = XML_PARSE_NOENT;
+
+	p = xmlReadFile(fileName, NULL, flags | XML_PARSE_OPTION_HARMLESS); // BAD (parser not correctly configured) [NOT DETECTED]
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_10(const char *ptr, int sz) {
+	xmlDoc *p;
+
+	p = xmlReadMemory(ptr, sz, "", NULL, 0); // GOOD
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}
+
+void test4_11(const char *ptr, int sz) {
+	xmlDoc *p;
+
+	p = xmlReadMemory(ptr, sz, "", NULL, XML_PARSE_DTDLOAD); // BAD (parser not correctly configured)
+	if (p != NULL)
+	{
+		xmlFreeDoc(p);
+	}
+}

cpp/ql/test/query-tests/Security/CWE/CWE-611/tests5.cpp

@@ -0,0 +1,78 @@
+// test cases for rule CWE-611 (createLSParser)
+
+#include "tests.h"
+
+// ---
+
+class DOMConfiguration {
+public:
+	void setParameter(const XMLCh *parameter, bool value);
+};
+
+class DOMLSParser {
+public:
+	DOMConfiguration *getDomConfig();
+
+	void parse(const InputSource &data);
+};
+
+class DOMImplementationLS {
+public:
+	DOMLSParser *createLSParser();
+};
+
+// ---
+
+void test5_1(DOMImplementationLS *impl, InputSource &data) {
+	DOMLSParser *p = impl->createLSParser();
+
+	p->parse(data); // BAD (parser not correctly configured) [NOT DETECTED]
+}
+
+void test5_2(DOMImplementationLS *impl, InputSource &data) {
+	DOMLSParser *p = impl->createLSParser();
+
+	p->getDomConfig()->setParameter(XMLUni::fgXercesDisableDefaultEntityResolution, true);
+	p->parse(data); // GOOD
+}
+
+void test5_3(DOMImplementationLS *impl, InputSource &data) {
+	DOMLSParser *p = impl->createLSParser();
+
+	p->getDomConfig()->setParameter(XMLUni::fgXercesDisableDefaultEntityResolution, false);
+	p->parse(data); // BAD (parser not correctly configured) [NOT DETECTED]
+}
+
+void test5_4(DOMImplementationLS *impl, InputSource &data) {
+	DOMLSParser *p = impl->createLSParser();
+	DOMConfiguration *cfg = p->getDomConfig();
+
+	cfg->setParameter(XMLUni::fgXercesDisableDefaultEntityResolution, true);
+	p->parse(data); // GOOD
+}
+
+void test5_5(DOMImplementationLS *impl, InputSource &data) {
+	DOMLSParser *p = impl->createLSParser();
+	DOMConfiguration *cfg = p->getDomConfig();
+
+	cfg->setParameter(XMLUni::fgXercesDisableDefaultEntityResolution, false);
+	p->parse(data); // BAD (parser not correctly configured) [NOT DETECTED]
+}
+
+DOMImplementationLS *g_impl;
+DOMLSParser *g_p1, *g_p2;
+InputSource *g_data;
+
+void test5_6_init() {
+	g_p1 = g_impl->createLSParser();
+	g_p1->getDomConfig()->setParameter(XMLUni::fgXercesDisableDefaultEntityResolution, true);
+
+	g_p2 = g_impl->createLSParser();
+}
+
+void test5_6() {
+	test5_6_init();
+
+	g_p1->parse(*g_data); // GOOD
+	g_p2->parse(*g_data); // BAD (parser not correctly configured) [NOT DETECTED]
+}

csharp/ql/campaigns/Solorigate/lib/CHANGELOG.md

@@ -1,3 +1,5 @@
+## 1.1.1
+
 ## 1.1.0
 
 ## 1.0.7

csharp/ql/campaigns/Solorigate/lib/change-notes/released/1.1.1.md

@@ -0,0 +1 @@
+## 1.1.1

csharp/ql/campaigns/Solorigate/lib/codeql-pack.release.yml

@@ -1,2 +1,2 @@
 ---
-lastReleaseVersion: 1.1.0
+lastReleaseVersion: 1.1.1

csharp/ql/campaigns/Solorigate/lib/qlpack.yml

@@ -1,5 +1,5 @@
 name: codeql/csharp-solorigate-all
-version: 1.1.1-dev
+version: 1.1.2-dev
 groups:
     - csharp
     - solorigate

csharp/ql/campaigns/Solorigate/src/CHANGELOG.md

@@ -1,3 +1,5 @@
+## 1.1.1
+
 ## 1.1.0
 
 ## 1.0.7

csharp/ql/campaigns/Solorigate/src/change-notes/released/1.1.1.md

@@ -0,0 +1 @@
+## 1.1.1

csharp/ql/campaigns/Solorigate/src/codeql-pack.release.yml

@@ -1,2 +1,2 @@
 ---
-lastReleaseVersion: 1.1.0
+lastReleaseVersion: 1.1.1

csharp/ql/campaigns/Solorigate/src/qlpack.yml

@@ -1,5 +1,5 @@
 name: codeql/csharp-solorigate-queries
-version: 1.1.1-dev
+version: 1.1.2-dev
 groups:
     - csharp
     - solorigate

csharp/ql/lib/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 0.2.0
+
+### Breaking Changes
+
+* The signature of `allowImplicitRead` on `DataFlow::Configuration` and `TaintTracking::Configuration` has changed from `allowImplicitRead(DataFlow::Node node, DataFlow::Content c)` to `allowImplicitRead(DataFlow::Node node, DataFlow::ContentSet c)`.
+
 ## 0.1.0
 
 ### Breaking Changes

csharp/ql/lib/change-notes/2022-04-25-allow-implicit-read-signature.md

@@ -1,4 +0,0 @@
----
-category: breaking
----
-The signature of `allowImplicitRead` on `DataFlow::Configuration` and `TaintTracking::Configuration` has changed from `allowImplicitRead(DataFlow::Node node, DataFlow::Content c)` to `allowImplicitRead(DataFlow::Node node, DataFlow::ContentSet c)`.

csharp/ql/lib/change-notes/released/0.2.0.md

@@ -0,0 +1,5 @@
+## 0.2.0
+
+### Breaking Changes
+
+* The signature of `allowImplicitRead` on `DataFlow::Configuration` and `TaintTracking::Configuration` has changed from `allowImplicitRead(DataFlow::Node node, DataFlow::Content c)` to `allowImplicitRead(DataFlow::Node node, DataFlow::ContentSet c)`.

csharp/ql/lib/codeql-pack.release.yml

@@ -1,2 +1,2 @@
 ---
-lastReleaseVersion: 0.1.0
+lastReleaseVersion: 0.2.0

csharp/ql/lib/qlpack.yml

@@ -1,5 +1,5 @@
 name: codeql/csharp-all
-version: 0.1.1-dev
+version: 0.2.1-dev
 groups: csharp
 dbscheme: semmlecode.csharp.dbscheme
 extractor: csharp

csharp/ql/lib/semmle/code/csharp/dataflow/internal/AccessPathSyntax.qll

@@ -167,9 +167,16 @@ class AccessPathToken extends string {
   /** Gets the `n`th argument to this token, such as `x` or `y` from `Member[x,y]`. */
   string getArgument(int n) { result = this.getArgumentList().splitAt(",", n).trim() }
 
+  /** Gets the `n`th argument to this `name` token, such as `x` or `y` from `Member[x,y]`. */
+  pragma[nomagic]
+  string getArgument(string name, int n) { name = this.getName() and result = this.getArgument(n) }
+
   /** Gets an argument to this token, such as `x` or `y` from `Member[x,y]`. */
   string getAnArgument() { result = this.getArgument(_) }
 
+  /** Gets an argument to this `name` token, such as `x` or `y` from `Member[x,y]`. */
+  string getAnArgument(string name) { result = this.getArgument(name, _) }
+
   /** Gets the number of arguments to this token, such as 2 for `Member[x,y]` or zero for `ReturnValue`. */
   int getNumArgument() { result = count(int n | exists(this.getArgument(n))) }
 }

csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImpl.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImpl2.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImpl3.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImpl4.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImpl5.qll

@@ -498,23 +498,35 @@ private predicate readSet(NodeEx node1, ContentSet c, NodeEx node2, Configuratio
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate read(NodeEx node1, Content c, NodeEx node2, Configuration config) {
   exists(ContentSet cs |
     readSet(node1, cs, node2, config) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
 // inline to reduce fan-out via `getAReadContent`
-pragma[inline]
+bindingset[c]
 private predicate clearsContentEx(NodeEx n, Content c) {
   exists(ContentSet cs |
     clearsContentCached(n.asNode(), cs) and
-    c = cs.getAReadContent()
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
   )
 }
 
+// inline to reduce fan-out via `getAReadContent`
+bindingset[c]
+private predicate expectsContentEx(NodeEx n, Content c) {
+  exists(ContentSet cs |
+    expectsContentCached(n.asNode(), cs) and
+    pragma[only_bind_out](c) = pragma[only_bind_into](cs).getAReadContent()
+  )
+}
+
+pragma[nomagic]
+private predicate notExpectsContent(NodeEx n) { not expectsContentCached(n.asNode(), _) }
+
 pragma[nomagic]
 private predicate store(
   NodeEx node1, TypedContent tc, NodeEx node2, DataFlowType contentType, Configuration config
@@ -793,7 +805,7 @@ private module Stage1 {
    * by `revFlow`.
    */
   pragma[nomagic]
-  private predicate revFlowIsReadAndStored(Content c, Configuration conf) {
+  predicate revFlowIsReadAndStored(Content c, Configuration conf) {
     revFlowConsCand(c, conf) and
     revFlowStore(c, _, _, conf)
   }
@@ -891,7 +903,7 @@ private module Stage1 {
 
   pragma[nomagic]
   predicate readStepCand(NodeEx n1, Content c, NodeEx n2, Configuration config) {
-    revFlowIsReadAndStored(pragma[only_bind_into](c), pragma[only_bind_into](config)) and
+    revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
     read(n1, c, n2, pragma[only_bind_into](config)) and
     revFlow(n2, pragma[only_bind_into](config))
   }
@@ -1181,11 +1193,26 @@ private module Stage2 {
 
   private predicate flowIntoCall = flowIntoCallNodeCand1/5;
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::revFlowIsReadAndStored(c, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c)
+    )
+  }
+
   bindingset[node, state, ap, config]
   private predicate filter(NodeEx node, FlowState state, Ap ap, Configuration config) {
     PrevStage::revFlowState(state, pragma[only_bind_into](config)) and
     exists(ap) and
-    not stateBarrier(node, state, config)
+    not stateBarrier(node, state, config) and
+    (
+      notExpectsContent(node)
+      or
+      ap = true and
+      expectsContentCand(node, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -1646,10 +1673,24 @@ private module Stage2 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -1740,7 +1781,8 @@ private module LocalFlowBigStep {
   private class FlowCheckNode extends NodeEx {
     FlowCheckNode() {
       castNode(this.asNode()) or
-      clearsContentCached(this.asNode(), _)
+      clearsContentCached(this.asNode(), _) or
+      expectsContentCached(this.asNode(), _)
     }
   }
 
@@ -1979,6 +2021,16 @@ private module Stage3 {
     clearContent(node, ap.getHead().getContent(), config)
   }
 
+  pragma[nomagic]
+  private predicate expectsContentCand(NodeEx node, Ap ap, Configuration config) {
+    exists(Content c |
+      PrevStage::revFlow(node, pragma[only_bind_into](config)) and
+      PrevStage::readStepCand(_, c, _, pragma[only_bind_into](config)) and
+      expectsContentEx(node, c) and
+      c = ap.getHead().getContent()
+    )
+  }
+
   pragma[nomagic]
   private predicate castingNodeEx(NodeEx node) { node.asNode() instanceof CastingNode }
 
@@ -1987,7 +2039,12 @@ private module Stage3 {
     exists(state) and
     exists(config) and
     not clear(node, ap, config) and
-    if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()
+    (if castingNodeEx(node) then compatibleTypes(node.getDataFlowType(), ap.getType()) else any()) and
+    (
+      notExpectsContent(node)
+      or
+      expectsContentCand(node, ap, config)
+    )
   }
 
   bindingset[ap, contentType]
@@ -2452,10 +2509,24 @@ private module Stage3 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3279,10 +3350,24 @@ private module Stage4 {
     storeStepFwd(_, ap, tc, _, _, config)
   }
 
-  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+  private predicate revConsCand(TypedContent tc, Ap ap, Configuration config) {
     storeStepCand(_, ap, tc, _, _, config)
   }
 
+  private predicate validAp(Ap ap, Configuration config) {
+    revFlow(_, _, _, _, ap, config) and ap instanceof ApNil
+    or
+    exists(TypedContent head, Ap tail |
+      consCand(head, tail, config) and
+      ap = apCons(head, tail)
+    )
+  }
+
+  predicate consCand(TypedContent tc, Ap ap, Configuration config) {
+    revConsCand(tc, ap, config) and
+    validAp(ap, config)
+  }
+
   pragma[noinline]
   private predicate parameterFlow(
     ParamNodeEx p, Ap ap, Ap ap0, DataFlowCallable c, Configuration config
@@ -3351,17 +3436,28 @@ private Configuration unbindConf(Configuration conf) {
   exists(Configuration c | result = pragma[only_bind_into](c) and conf = pragma[only_bind_into](c))
 }
 
-private predicate nodeMayUseSummary(
-  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+pragma[nomagic]
+private predicate nodeMayUseSummary0(
+  NodeEx n, DataFlowCallable c, FlowState state, AccessPathApprox apa, Configuration config
 ) {
-  exists(DataFlowCallable c, AccessPathApprox apa0 |
-    Stage4::parameterMayFlowThrough(_, c, apa, _) and
+  exists(AccessPathApprox apa0 |
+    Stage4::parameterMayFlowThrough(_, c, _, _) and
     Stage4::revFlow(n, state, true, _, apa0, config) and
     Stage4::fwdFlow(n, state, any(CallContextCall ccc), TAccessPathApproxSome(apa), apa0, config) and
     n.getEnclosingCallable() = c
   )
 }
 
+pragma[nomagic]
+private predicate nodeMayUseSummary(
+  NodeEx n, FlowState state, AccessPathApprox apa, Configuration config
+) {
+  exists(DataFlowCallable c |
+    Stage4::parameterMayFlowThrough(_, c, apa, config) and
+    nodeMayUseSummary0(n, c, state, apa, config)
+  )
+}
+
 private newtype TSummaryCtx =
   TSummaryCtxNone() or
   TSummaryCtxSome(ParamNodeEx p, FlowState state, AccessPath ap) {
@@ -4257,6 +4353,12 @@ private module Subpaths {
     )
   }
 
+  pragma[nomagic]
+  private predicate hasSuccessor(PathNode pred, PathNodeMid succ, NodeEx succNode) {
+    succ = pred.getASuccessor() and
+    succNode = succ.getNodeEx()
+  }
+
   /**
    * Holds if `(arg, par, ret, out)` forms a subpath-tuple, that is, flow through
    * a subpath between `par` and `ret` with the connecting edges `arg -> par` and
@@ -4264,15 +4366,13 @@ private module Subpaths {
    */
   predicate subpaths(PathNode arg, PathNodeImpl par, PathNodeImpl ret, PathNode out) {
     exists(ParamNodeEx p, NodeEx o, FlowState sout, AccessPath apout, PathNodeMid out0 |
-      pragma[only_bind_into](arg).getASuccessor() = par and
-      pragma[only_bind_into](arg).getASuccessor() = out0 and
-      subpaths03(arg, p, localStepToHidden*(ret), o, sout, apout) and
+      pragma[only_bind_into](arg).getASuccessor() = pragma[only_bind_into](out0) and
+      subpaths03(pragma[only_bind_into](arg), p, localStepToHidden*(ret), o, sout, apout) and
+      hasSuccessor(pragma[only_bind_into](arg), par, p) and
       not ret.isHidden() and
-      par.getNodeEx() = p and
-      out0.getNodeEx() = o and
-      out0.getState() = sout and
-      out0.getAp() = apout and
-      (out = out0 or out = out0.projectToSink())
+      pathNode(out0, o, sout, _, _, apout, _, _)
+    |
+      out = out0 or out = out0.projectToSink()
     )
   }
 
@@ -4609,6 +4709,10 @@ private module FlowExploration {
       exists(PartialPathNodeRev mid |
         revPartialPathStep(mid, node, state, sc1, sc2, sc3, ap, config) and
         not clearsContentEx(node, ap.getHead()) and
+        (
+          notExpectsContent(node) or
+          expectsContentEx(node, ap.getHead())
+        ) and
         not fullBarrier(node, config) and
         not stateBarrier(node, state, config) and
         distSink(node.getEnclosingCallable(), config) <= config.explorationLimit()
@@ -4625,6 +4729,10 @@ private module FlowExploration {
       not fullBarrier(node, config) and
       not stateBarrier(node, state, config) and
       not clearsContentEx(node, ap.getHead().getContent()) and
+      (
+        notExpectsContent(node) or
+        expectsContentEx(node, ap.getHead().getContent())
+      ) and
       if node.asNode() instanceof CastingNode
       then compatibleTypes(node.getDataFlowType(), ap.getType())
       else any()

csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowImplCommon.qll

@@ -328,6 +328,9 @@ private module Cached {
   cached
   predicate clearsContentCached(Node n, ContentSet c) { clearsContent(n, c) }
 
+  cached
+  predicate expectsContentCached(Node n, ContentSet c) { expectsContent(n, c) }
+
   cached
   predicate isUnreachableInCallCached(Node n, DataFlowCall call) { isUnreachableInCall(n, call) }
 

csharp/ql/lib/semmle/code/csharp/dataflow/internal/DataFlowPrivate.qll

@@ -421,7 +421,7 @@ predicate simpleLocalFlowStep(Node nodeFrom, Node nodeTo) {
   or
   exists(Ssa::Definition def |
     LocalFlow::localSsaFlowStepUseUse(def, nodeFrom, nodeTo) and
-    not FlowSummaryImpl::Private::Steps::summaryClearsContentArg(nodeFrom, _) and
+    not FlowSummaryImpl::Private::Steps::prohibitsUseUseFlow(nodeFrom) and
     not LocalFlow::usesInstanceField(def)
   )
   or
@@ -1714,6 +1714,14 @@ predicate clearsContent(Node n, Content c) {
   )
 }
 
+/**
+ * Holds if the value that is being tracked is expected to be stored inside content `c`
+ * at node `n`.
+ */
+predicate expectsContent(Node n, ContentSet c) {
+  FlowSummaryImpl::Private::Steps::summaryExpectsContent(n, c)
+}
+
 /**
  * Holds if the node `n` is unreachable when the call context is `call`.
  */

csharp/ql/lib/semmle/code/csharp/dataflow/internal/FlowSummaryImpl.qll

@@ -26,6 +26,10 @@ module Public {
     string toString() {
       exists(ContentSet c | this = TContentSummaryComponent(c) and result = c.toString())
       or
+      exists(ContentSet c | this = TWithoutContentSummaryComponent(c) and result = "without " + c)
+      or
+      exists(ContentSet c | this = TWithContentSummaryComponent(c) and result = "with " + c)
+      or
       exists(ArgumentPosition pos |
         this = TParameterSummaryComponent(pos) and result = "parameter " + pos
       )
@@ -43,6 +47,12 @@ module Public {
     /** Gets a summary component for content `c`. */
     SummaryComponent content(ContentSet c) { result = TContentSummaryComponent(c) }
 
+    /** Gets a summary component where data is not allowed to be stored in `c`. */
+    SummaryComponent withoutContent(ContentSet c) { result = TWithoutContentSummaryComponent(c) }
+
+    /** Gets a summary component where data must be stored in `c`. */
+    SummaryComponent withContent(ContentSet c) { result = TWithContentSummaryComponent(c) }
+
     /** Gets a summary component for a parameter at position `pos`. */
     SummaryComponent parameter(ArgumentPosition pos) { result = TParameterSummaryComponent(pos) }
 
@@ -216,9 +226,16 @@ module Public {
     /**
      * Holds if values stored inside `content` are cleared on objects passed as
      * arguments at position `pos` to this callable.
+     *
+     * TODO: Remove once all languages support `WithoutContent` tokens.
      */
     pragma[nomagic]
     predicate clearsContent(ParameterPosition pos, ContentSet content) { none() }
+
+    /**
+     * Holds if the summary is auto generated.
+     */
+    predicate isAutoGenerated() { none() }
   }
 }
 
@@ -234,7 +251,9 @@ module Private {
     TContentSummaryComponent(ContentSet c) or
     TParameterSummaryComponent(ArgumentPosition pos) or
     TArgumentSummaryComponent(ParameterPosition pos) or
-    TReturnSummaryComponent(ReturnKind rk)
+    TReturnSummaryComponent(ReturnKind rk) or
+    TWithoutContentSummaryComponent(ContentSet c) or
+    TWithContentSummaryComponent(ContentSet c)
 
   private TParameterSummaryComponent thisParam() {
     result = TParameterSummaryComponent(instanceParameterPosition())
@@ -296,6 +315,23 @@ module Private {
           SummaryComponentStack::singleton(TArgumentSummaryComponent(_))) and
       preservesValue = preservesValue1.booleanAnd(preservesValue2)
     )
+    or
+    exists(ParameterPosition ppos, ContentSet cs |
+      c.clearsContent(ppos, cs) and
+      input = SummaryComponentStack::push(SummaryComponent::withoutContent(cs), output) and
+      output = SummaryComponentStack::argument(ppos) and
+      preservesValue = true
+    )
+  }
+
+  private class MkClearStack extends RequiredSummaryComponentStack {
+    override predicate required(SummaryComponent head, SummaryComponentStack tail) {
+      exists(SummarizedCallable sc, ParameterPosition ppos, ContentSet cs |
+        sc.clearsContent(ppos, cs) and
+        head = SummaryComponent::withoutContent(cs) and
+        tail = SummaryComponentStack::argument(ppos)
+      )
+    }
   }
 
   /**
@@ -378,10 +414,7 @@ module Private {
 
   private newtype TSummaryNodeState =
     TSummaryNodeInputState(SummaryComponentStack s) { inputState(_, s) } or
-    TSummaryNodeOutputState(SummaryComponentStack s) { outputState(_, s) } or
-    TSummaryNodeClearsContentState(ParameterPosition pos, boolean post) {
-      any(SummarizedCallable sc).clearsContent(pos, _) and post in [false, true]
-    }
+    TSummaryNodeOutputState(SummaryComponentStack s) { outputState(_, s) }
 
   /**
    * A state used to break up (complex) flow summaries into atomic flow steps.
@@ -428,12 +461,6 @@ module Private {
         this = TSummaryNodeOutputState(s) and
         result = "to write: " + s
       )
-      or
-      exists(ParameterPosition pos, boolean post, string postStr |
-        this = TSummaryNodeClearsContentState(pos, post) and
-        (if post = true then postStr = " (post)" else postStr = "") and
-        result = "clear: " + pos + postStr
-      )
     }
   }
 
@@ -457,11 +484,6 @@ module Private {
     not parameterReadState(c, state, _)
     or
     state.isOutputState(c, _)
-    or
-    exists(ParameterPosition pos |
-      c.clearsContent(pos, _) and
-      state = TSummaryNodeClearsContentState(pos, _)
-    )
   }
 
   pragma[noinline]
@@ -497,8 +519,6 @@ module Private {
     parameterReadState(c, _, pos)
     or
     isParameterPostUpdate(_, c, pos)
-    or
-    c.clearsContent(pos, _)
   }
 
   private predicate callbackOutput(
@@ -506,7 +526,7 @@ module Private {
   ) {
     any(SummaryNodeState state).isInputState(c, s) and
     s.head() = TReturnSummaryComponent(rk) and
-    receiver = summaryNodeInputState(c, s.drop(1))
+    receiver = summaryNodeInputState(c, s.tail())
   }
 
   private predicate callbackInput(
@@ -514,7 +534,7 @@ module Private {
   ) {
     any(SummaryNodeState state).isOutputState(c, s) and
     s.head() = TParameterSummaryComponent(pos) and
-    receiver = summaryNodeInputState(c, s.drop(1))
+    receiver = summaryNodeInputState(c, s.tail())
   }
 
   /** Holds if a call targeting `receiver` should be synthesized inside `c`. */
@@ -540,15 +560,21 @@ module Private {
     exists(SummarizedCallable c, SummaryComponentStack s, SummaryComponent head | head = s.head() |
       n = summaryNodeInputState(c, s) and
       (
+        exists(ContentSet cont | result = getContentType(cont) |
+          head = TContentSummaryComponent(cont) or
+          head = TWithContentSummaryComponent(cont)
+        )
+        or
         exists(ContentSet cont |
-          head = TContentSummaryComponent(cont) and result = getContentType(cont)
+          head = TWithoutContentSummaryComponent(cont) and
+          result = getNodeType(summaryNodeInputState(c, s.tail()))
         )
         or
         exists(ReturnKind rk |
           head = TReturnSummaryComponent(rk) and
           result =
             getCallbackReturnType(getNodeType(summaryNodeInputState(pragma[only_bind_out](c),
-                  s.drop(1))), rk)
+                  s.tail())), rk)
         )
       )
       or
@@ -567,16 +593,10 @@ module Private {
         exists(ArgumentPosition pos | head = TParameterSummaryComponent(pos) |
           result =
             getCallbackParameterType(getNodeType(summaryNodeInputState(pragma[only_bind_out](c),
-                  s.drop(1))), pos)
+                  s.tail())), pos)
         )
       )
     )
-    or
-    exists(SummarizedCallable c, ParameterPosition pos, ParamNode p |
-      n = summaryNode(c, TSummaryNodeClearsContentState(pos, false)) and
-      p.isParameterOf(c, pos) and
-      result = getNodeType(p)
-    )
   }
 
   /** Holds if summary node `out` contains output of kind `rk` from call `c`. */
@@ -602,9 +622,6 @@ module Private {
     exists(SummarizedCallable c, ParameterPosition pos |
       isParameterPostUpdate(post, c, pos) and
       pre.(ParamNode).isParameterOf(c, pos)
-      or
-      pre = summaryNode(c, TSummaryNodeClearsContentState(pos, false)) and
-      post = summaryNode(c, TSummaryNodeClearsContentState(pos, true))
     )
     or
     exists(SummarizedCallable callable, SummaryComponentStack s |
@@ -628,8 +645,6 @@ module Private {
    */
   predicate summaryAllowParameterReturnInSelf(ParamNode p) {
     exists(SummarizedCallable c, ParameterPosition ppos | p.isParameterOf(c, ppos) |
-      c.clearsContent(ppos, _)
-      or
       exists(SummaryComponentStack inputContents, SummaryComponentStack outputContents |
         summary(c, inputContents, outputContents, _) and
         inputContents.bottom() = pragma[only_bind_into](TArgumentSummaryComponent(ppos)) and
@@ -658,9 +673,10 @@ module Private {
         preservesValue = false and not summary(c, inputContents, outputContents, true)
       )
       or
-      exists(SummarizedCallable c, ParameterPosition pos |
-        pred.(ParamNode).isParameterOf(c, pos) and
-        succ = summaryNode(c, TSummaryNodeClearsContentState(pos, _)) and
+      exists(SummarizedCallable c, SummaryComponentStack s |
+        pred = summaryNodeInputState(c, s.tail()) and
+        succ = summaryNodeInputState(c, s) and
+        s.head() = [SummaryComponent::withContent(_), SummaryComponent::withoutContent(_)] and
         preservesValue = true
       )
     }
@@ -671,7 +687,7 @@ module Private {
      */
     predicate summaryReadStep(Node pred, ContentSet c, Node succ) {
       exists(SummarizedCallable sc, SummaryComponentStack s |
-        pred = summaryNodeInputState(sc, s.drop(1)) and
+        pred = summaryNodeInputState(sc, s.tail()) and
         succ = summaryNodeInputState(sc, s) and
         SummaryComponent::content(c) = s.head()
       )
@@ -684,7 +700,7 @@ module Private {
     predicate summaryStoreStep(Node pred, ContentSet c, Node succ) {
       exists(SummarizedCallable sc, SummaryComponentStack s |
         pred = summaryNodeOutputState(sc, s) and
-        succ = summaryNodeOutputState(sc, s.drop(1)) and
+        succ = summaryNodeOutputState(sc, s.tail()) and
         SummaryComponent::content(c) = s.head()
       )
     }
@@ -709,9 +725,22 @@ module Private {
      * node where field `b` is cleared).
      */
     predicate summaryClearsContent(Node n, ContentSet c) {
-      exists(SummarizedCallable sc, ParameterPosition pos |
-        n = summaryNode(sc, TSummaryNodeClearsContentState(pos, true)) and
-        sc.clearsContent(pos, c)
+      exists(SummarizedCallable sc, SummaryNodeState state, SummaryComponentStack stack |
+        n = summaryNode(sc, state) and
+        state.isInputState(sc, stack) and
+        stack.head() = SummaryComponent::withoutContent(c)
+      )
+    }
+
+    /**
+     * Holds if the value that is being tracked is expected to be stored inside
+     * content `c` at `n`.
+     */
+    predicate summaryExpectsContent(Node n, ContentSet c) {
+      exists(SummarizedCallable sc, SummaryNodeState state, SummaryComponentStack stack |
+        n = summaryNode(sc, state) and
+        state.isInputState(sc, stack) and
+        stack.head() = SummaryComponent::withContent(c)
       )
     }
 
@@ -723,22 +752,6 @@ module Private {
       sc = viableCallable(call)
     }
 
-    /**
-     * Holds if values stored inside content `c` are cleared inside a
-     * callable to which `arg` is an argument.
-     *
-     * In such cases, it is important to prevent use-use flow out of
-     * `arg` (see comment for `summaryClearsContent`).
-     */
-    pragma[nomagic]
-    predicate summaryClearsContentArg(ArgNode arg, ContentSet c) {
-      exists(DataFlowCall call, SummarizedCallable sc, ParameterPosition ppos |
-        argumentPositionMatch(call, arg, ppos) and
-        viableParam(call, sc, ppos, _) and
-        sc.clearsContent(ppos, c)
-      )
-    }
-
     pragma[nomagic]
     private ParamNode summaryArgParam0(DataFlowCall call, ArgNode arg) {
       exists(ParameterPosition ppos, SummarizedCallable sc |
@@ -747,6 +760,27 @@ module Private {
       )
     }
 
+    /**
+     * Holds if use-use flow starting from `arg` should be prohibited.
+     *
+     * This is the case when `arg` is the argument of a call that targets a
+     * flow summary where the corresponding parameter either clears contents
+     * or expects contents.
+     */
+    pragma[nomagic]
+    predicate prohibitsUseUseFlow(ArgNode arg) {
+      exists(ParamNode p, Node mid, ParameterPosition ppos, Node ret |
+        p = summaryArgParam0(_, arg) and
+        p.isParameterOf(_, ppos) and
+        summaryLocalStep(p, mid, true) and
+        summaryLocalStep(mid, ret, true) and
+        isParameterPostUpdate(ret, _, ppos)
+      |
+        summaryClearsContent(mid, _) or
+        summaryExpectsContent(mid, _)
+      )
+    }
+
     pragma[nomagic]
     private ParamNode summaryArgParam(ArgNode arg, ReturnKindExt rk, OutNodeExt out) {
       exists(DataFlowCall call |
@@ -898,6 +932,8 @@ module Private {
           kind = "taint" and preservesValue = false
         )
       }
+
+      override predicate isAutoGenerated() { summaryElement(this, _, _, _, true) }
     }
 
     /** Holds if component `c` of specification `spec` cannot be parsed. */
@@ -1052,9 +1088,13 @@ module Private {
       preservesValue = false and result = "taint"
     }
 
+    private string renderGenerated(RelevantSummarizedCallable c) {
+      if c.isAutoGenerated() then result = "generated:" else result = ""
+    }
+
     /**
      * A query predicate for outputting flow summaries in semi-colon separated format in QL tests.
-     * The syntax is: "namespace;type;overrides;name;signature;ext;inputspec;outputspec;kind",
+     * The syntax is: "namespace;type;overrides;name;signature;ext;inputspec;outputspec;(generated:)?kind",
      * ext is hardcoded to empty.
      */
     query predicate summary(string csv) {
@@ -1065,7 +1105,7 @@ module Private {
         c.relevantSummary(input, output, preservesValue) and
         csv =
           c.getCallableCsv() + getComponentStackCsv(input) + ";" + getComponentStackCsv(output) +
-            ";" + renderKind(preservesValue)
+            ";" + renderGenerated(c) + renderKind(preservesValue)
       )
     }
   }
@@ -1141,6 +1181,10 @@ module Private {
         Private::Steps::summaryClearsContent(a.asNode(), c) and
         b = a and
         value = "clear (" + c + ")"
+        or
+        Private::Steps::summaryExpectsContent(a.asNode(), c) and
+        b = a and
+        value = "expect (" + c + ")"
       )
       or
       summaryPostUpdateNode(b.asNode(), a.asNode()) and

csharp/ql/lib/semmle/code/csharp/dataflow/internal/rangeanalysis/SignAnalysisCommon.qll

@@ -49,7 +49,7 @@ private predicate unknownSign(Expr e) {
     or
     exists(LongLiteral lit | lit = e and not exists(lit.getValue().toFloat()))
     or
-    exists(CastExpr cast, Type fromtyp |
+    exists(CastingExpr cast, Type fromtyp |
       cast = e and
       fromtyp = cast.getSourceType() and
       not fromtyp instanceof NumericOrCharType

csharp/ql/lib/semmle/code/csharp/dataflow/internal/rangeanalysis/SignAnalysisSpecific.qll

@@ -29,6 +29,8 @@ module Private {
 
   class CastExpr = RU::ExprNode::CastExpr;
 
+  class CastingExpr = CastExpr;
+
   class Type = CS::Type;
 
   class Expr = CS::ControlFlow::Nodes::ExprNode;

csharp/ql/lib/semmle/code/csharp/exprs/Call.qll

@@ -175,8 +175,8 @@ class Call extends DotNet::Call, Expr, @call {
    * - Line 10: The static target is `Type.InvokeMember()`, whereas the run-time targets
    *   are both `A.M()` and `B.M()`.
    *
-   * - Line 16: There is no static target (delegate call) but the delegate `i => { }` (line
-   *   20) is a run-time target.
+   * - Line 16: There is no static target (delegate call) but the delegate `i => { }`
+   *   (line 20) is a run-time target.
    */
   override Callable getARuntimeTarget() {
     exists(DispatchCall dc | dc.getCall() = this | result = dc.getADynamicTarget())

csharp/ql/lib/semmle/code/csharp/frameworks/system/Collections.qll

@@ -55,7 +55,7 @@ private class SystemCollectionsIEnumerableClearFlow extends SummarizedCallable {
   }
 
   override predicate clearsContent(ParameterPosition pos, DataFlow::ContentSet content) {
-    pos.isThisParameter() and
+    (if this.(Modifiable).isStatic() then pos.getPosition() = 0 else pos.isThisParameter()) and
     content instanceof DataFlow::ElementContent
   }
 }

csharp/ql/src/API Abuse/IncorrectCompareToSignature.ql

@@ -1,6 +1,6 @@
 /**
  * @name Potentially incorrect CompareTo(...) signature
- * @description The declaring type of a method with signature 'CompareTo(T)' does not implement 'IComparable<T>'.
+ * @description The declaring type of a method with signature `CompareTo(T)` does not implement `IComparable<T>`.
  * @kind problem
  * @problem.severity warning
  * @precision medium

csharp/ql/src/CHANGELOG.md

@@ -1,3 +1,5 @@
+## 0.1.1
+
 ## 0.1.0
 
 ## 0.0.13

csharp/ql/src/Documentation/XmldocExtraParam.ql

@@ -1,6 +1,6 @@
 /**
  * @name Incorrect parameter name in documentation
- * @description The parameter name given in a '<param>' tag does not exist. Rename the parameter or
+ * @description The parameter name given in a `<param>` tag does not exist. Rename the parameter or
  *              change the name in the documentation to ensure that they are the same.
  * @kind problem
  * @problem.severity recommendation

csharp/ql/src/Documentation/XmldocExtraTypeParam.ql

@@ -1,6 +1,6 @@
 /**
  * @name Incorrect type parameter name in documentation
- * @description The type parameter name given in a '<typeparam>' tag does not exist. Rename the parameter or
+ * @description The type parameter name given in a `<typeparam>` tag does not exist. Rename the parameter or
  *              change the name in the documentation to ensure that they are the same.
  * @kind problem
  * @problem.severity recommendation

csharp/ql/src/Documentation/XmldocMissingException.ql

@@ -1,6 +1,6 @@
 /**
  * @name Missing documentation for exception
- * @description Exceptions thrown by the method should be documented using '<exception cref="..."> </exception>' tags.
+ * @description Exceptions thrown by the method should be documented using `<exception cref="..."> </exception>` tags.
  *              Ensure that the correct type of the exception is given in the 'cref' attribute.
  * @kind problem
  * @problem.severity recommendation

csharp/ql/src/Documentation/XmldocMissingParam.ql

@@ -1,6 +1,6 @@
 /**
  * @name Missing documentation for parameter
- * @description All parameters should be documented using '<param name="..."> </param>' tags.
+ * @description All parameters should be documented using `<param name="..."> </param>` tags.
  *              Ensure that the name attribute matches the name of the parameter.
  * @kind problem
  * @problem.severity recommendation

csharp/ql/src/Documentation/XmldocMissingReturn.ql

@@ -1,7 +1,7 @@
 /**
  * @name Missing documentation for return value
  * @description The method returns a value, but the return value is not documented using
- *              a '<returns>' tag.
+ *              a `<returns>` tag.
  * @kind problem
  * @problem.severity recommendation
  * @precision low

csharp/ql/src/Documentation/XmldocMissingSummary.ql

@@ -1,6 +1,6 @@
 /**
  * @name Missing a summary in documentation comment
- * @description The documentation comment does not contain a '<summary>' tag.
+ * @description The documentation comment does not contain a `<summary>` tag.
  * @kind problem
  * @problem.severity recommendation
  * @precision high

csharp/ql/src/Documentation/XmldocMissingTypeParam.ql

@@ -1,6 +1,6 @@
 /**
  * @name Missing documentation for type parameter
- * @description All type parameters should be documented using '<typeparam name="..."> </typeparam>' tags.
+ * @description All type parameters should be documented using `<typeparam name="..."> </typeparam>` tags.
  *              Ensure that the 'name' attribute matches the name of the type parameter.
  * @kind problem
  * @problem.severity recommendation

csharp/ql/src/Security Features/CWE-091/XMLInjection.ql

@@ -2,7 +2,7 @@
  * @name XML injection
  * @description Building an XML document from user-controlled sources is vulnerable to insertion of
  *              malicious code by the user.
- * @kind problem
+ * @kind path-problem
  * @id cs/xml-injection
  * @problem.severity error
  * @security-severity 8.8
@@ -12,6 +12,7 @@
  */
 
 import csharp
+import DataFlow::PathGraph
 import semmle.code.csharp.security.dataflow.flowsources.Remote
 import semmle.code.csharp.frameworks.system.Xml
 
@@ -45,6 +46,6 @@ class TaintTrackingConfiguration extends TaintTracking::Configuration {
   }
 }
 
-from TaintTrackingConfiguration c, DataFlow::Node source, DataFlow::Node sink
-where c.hasFlow(source, sink)
-select sink, "$@ flows to here and is inserted as XML.", source, "User-provided value"
+from TaintTrackingConfiguration c, DataFlow::PathNode source, DataFlow::PathNode sink
+where c.hasFlowPath(source, sink)
+select sink, source, sink, "$@ flows to here and is inserted as XML.", source, "User-provided value"

csharp/ql/src/Stubs/make_stubs_nuget.py

@@ -71,7 +71,7 @@ if (version != "latest"):
     cmd.append(version)
 run_cmd(cmd)
 
-sdk_version = '6.0.101'
+sdk_version = '6.0.202'
 print("\n* Creating new global.json file and setting SDK to " + sdk_version)
 run_cmd(['dotnet', 'new', 'globaljson', '--force', '--sdk-version', sdk_version, '--output', workDir])
 

csharp/ql/src/Telemetry/ExternalLibraryUsage.ql

@@ -2,7 +2,7 @@
  * @name External libraries
  * @description A list of external libraries used in the code
  * @kind metric
- * @tags summary
+ * @tags summary telemetry
  * @id csharp/telemetry/external-libs
  */
 

csharp/ql/src/Telemetry/SupportedExternalSinks.ql

@@ -2,7 +2,7 @@
  * @name Supported sinks in external libraries
  * @description A list of 3rd party APIs detected as sinks. Excludes APIs exposed by test libraries.
  * @kind metric
- * @tags summary
+ * @tags summary telemetry
  * @id csharp/telemetry/supported-external-api-sinks
  */
 

csharp/ql/src/Telemetry/SupportedExternalSources.ql

@@ -2,7 +2,7 @@
  * @name Supported sources in external libraries
  * @description A list of 3rd party APIs detected as sources. Excludes APIs exposed by test libraries.
  * @kind metric
- * @tags summary
+ * @tags summary telemetry
  * @id csharp/telemetry/supported-external-api-sources
  */
 

csharp/ql/src/Telemetry/SupportedExternalTaint.ql

@@ -2,7 +2,7 @@
  * @name Supported flow steps in external libraries
  * @description A list of 3rd party APIs detected as flow steps. Excludes APIs exposed by test libraries.
  * @kind metric
- * @tags summary
+ * @tags summary telemetry
  * @id csharp/telemetry/supported-external-api-taint
  */
 

csharp/ql/src/Telemetry/UnsupportedExternalAPIs.ql

@@ -2,7 +2,7 @@
  * @name Usage of unsupported APIs coming from external libraries
  * @description A list of 3rd party APIs used in the codebase. Excludes APIs exposed by test libraries.
  * @kind metric
- * @tags summary
+ * @tags summary telemetry
  * @id csharp/telemetry/unsupported-external-api
  */
 

csharp/ql/src/change-notes/released/0.1.1.md

@@ -0,0 +1 @@
+## 0.1.1