Delete CompilerRemovalOfCodeToClearBuffers.ql

sorry i was in a hurry

cpp/ql/src/experimental/Security/CWE/CWE-14/CompilerRemovalOfCodeToClearBuffers.ql

@@ -1,121 +0,0 @@
-/**
- * @name Compiler Removal Of Code To Clear Buffers
- * @description --Using the memset function to clear private data as a final expression when working with a variable is potentially dangerous because the compiler can optimize this call.
- *              --For some compilers, optimization is also possible when using calls to free memory after the memset function.
- *              --To clear it, you need to use the RtlSecureZeroMemory or memset_s functions, or compilation flags that exclude optimization of memset calls (-fno-builtin-memset).
- * @kind problem
- * @id cpp/compiler-removal-of-code-to-clear-buffers
- * @problem.severity warning
- * @precision medium
- * @tags security
- *       external/cwe/cwe-14
- */
-
-import cpp
-import semmle.code.cpp.dataflow.DataFlow
-
-/**
- * A call to `memset` , for some local variable.
- */
-class CompilerRemovaMemset extends FunctionCall {
-  CompilerRemovaMemset() {
-    this.getTarget().hasName("memset") and
-    exists(DataFlow::Node source, DataFlow::Node sink, LocalVariable isv, Expr exp |
-      DataFlow::localFlow(source, sink) and
-      this.getArgument(0) = isv.getAnAccess() and
-      source.asExpr() = exp and
-      exp.getLocation().getEndLine() < this.getArgument(0).getLocation().getStartLine() and
-      sink.asExpr() = this.getArgument(0)
-    )
-  }
-
-  predicate isExistsAllocForThisVariable() {
-    exists(FunctionCall alloc, Variable v |
-      alloc = v.getAnAssignedValue() and
-      this.getArgument(0) = v.getAnAccess() and
-      alloc.getASuccessor+() = this
-    )
-  }
-
-  predicate isExistsFreeForThisVariable() {
-    exists(FunctionCall free, Variable v |
-      free instanceof DeallocationExpr and
-      this.getArgument(0) = v.getAnAccess() and
-      free.getArgument(0) = v.getAnAccess() and
-      this.getASuccessor+() = free
-    )
-  }
-
-  predicate isExistsCallWithThisVariableExcludingDeallocationCalls() {
-    exists(FunctionCall fc, Variable v |
-      not fc instanceof DeallocationExpr and
-      this.getArgument(0) = v.getAnAccess() and
-      fc.getAnArgument() = v.getAnAccess() and
-      this.getASuccessor+() = fc
-    )
-  }
-
-  predicate isVariableUseAfterMemsetExcludingCalls() {
-    exists(DataFlow::Node source, DataFlow::Node sink, LocalVariable isv, Expr exp |
-      DataFlow::localFlow(source, sink) and
-      this.getArgument(0) = isv.getAnAccess() and
-      source.asExpr() = isv.getAnAccess() and
-      exp.getLocation().getStartLine() > this.getArgument(2).getLocation().getEndLine() and
-      not exp.getParent() instanceof FunctionCall and
-      sink.asExpr() = exp
-    )
-  }
-
-  predicate isVariableUseBoundWithArgumentFunction() {
-    exists(DataFlow::Node source, DataFlow::Node sink, LocalVariable isv, Parameter p, Expr exp |
-      DataFlow::localFlow(source, sink) and
-      this.getArgument(0) = isv.getAnAccess() and
-      this.getEnclosingFunction().getAParameter() = p and
-      exp.getAChild*() = p.getAnAccess() and
-      source.asExpr() = exp and
-      sink.asExpr() = isv.getAnAccess()
-    )
-  }
-
-  predicate isVariableUseBoundWithGlobalVariable() {
-    exists(
-      DataFlow::Node source, DataFlow::Node sink, LocalVariable isv, GlobalVariable gv, Expr exp
-    |
-      DataFlow::localFlow(source, sink) and
-      this.getArgument(0) = isv.getAnAccess() and
-      exp.getAChild*() = gv.getAnAccess() and
-      source.asExpr() = exp and
-      sink.asExpr() = isv.getAnAccess()
-    )
-  }
-
-  predicate isExistsCompilationFlagsBlockingRemoval() {
-    exists(Compilation c |
-      c.getAFileCompiled() = this.getFile() and
-      c.getAnArgument() = "-fno-builtin-memset"
-    )
-  }
-
-  predicate isUseVCCompilation() {
-    exists(Compilation c |
-      c.getAFileCompiled() = this.getFile() and
-      (
-        c.getArgument(2).toString().matches("%gcc%") or
-        c.getArgument(2).toString().matches("%g++%") or
-        c.getArgument(2).toString().matches("%clang%") or
-        c.getArgument(2).toString() = "--force-recompute"
-      )
-    )
-  }
-}
-
-from CompilerRemovaMemset fc
-where
-  not (fc.isExistsAllocForThisVariable() and not fc.isExistsFreeForThisVariable()) and
-  not (fc.isExistsFreeForThisVariable() and not fc.isUseVCCompilation()) and
-  not fc.isVariableUseAfterMemsetExcludingCalls() and
-  not fc.isExistsCallWithThisVariableExcludingDeallocationCalls() and
-  not fc.isVariableUseBoundWithArgumentFunction() and
-  not fc.isVariableUseBoundWithGlobalVariable() and
-  not fc.isExistsCompilationFlagsBlockingRemoval()
-select fc.getArgument(0), "this variable will not be cleared"