hohn/codeql
1
0
Fork 0
mirror of https://github.com/github/codeql.git synced 2026-04-28 02:05:14 +02:00
Code Issues Packages Projects Releases Wiki Activity

JS: sharpen js/unneeded-defensive-code for negations and sequences

Browse Source
This commit is contained in:
Esben Sparre Andreasen
2019-01-21 08:12:47 +01:00
parent cf3a4ac956
commit 9e4613094a
5 changed files with 22 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
javascript/ql/src/semmle/javascript/DefensiveProgramming.qll
View File

@@ -53,7 +53,7 @@ module Internal {
* `polarity` is true iff the inner expression is nested in an even number of negations.
*/
private Expr stripNotsAndParens(Expr e, boolean polarity) {
exists(Expr inner | inner = e.getUnderlyingValue() |
exists(Expr inner | inner = e.stripParens() |
if inner instanceof LogNotExpr
then result = stripNotsAndParens(inner.(LogNotExpr).getOperand(), polarity.booleanNot())
else (
@@ -199,11 +199,14 @@ module Internal {
Expr target;
UndefinedNullCrashUse() {
this.(InvokeExpr).getCallee().getUnderlyingValue() = target
or
this.(PropAccess).getBase().getUnderlyingValue() = target
or
this.(MethodCallExpr).getReceiver().getUnderlyingValue() = target
exists (Expr thrower |
stripNotsAndParens(this, _) = thrower |
thrower.(InvokeExpr).getCallee().getUnderlyingValue() = target
or
thrower.(PropAccess).getBase().getUnderlyingValue() = target
or
thrower.(MethodCallExpr).getReceiver().getUnderlyingValue() = target
)
}
/**
@@ -220,7 +223,8 @@ module Internal {
private class NonFunctionCallCrashUse extends Expr {
Expr target;
NonFunctionCallCrashUse() { this.(InvokeExpr).getCallee().getUnderlyingValue() = target }
NonFunctionCallCrashUse() {
stripNotsAndParens(this, _).(InvokeExpr).getCallee().getUnderlyingValue() = target }
/**
* Gets the subexpression that will cause an exception to be thrown if it is not a `function`.
@@ -273,7 +277,6 @@ module Internal {
guardVar.getVariable() = useVar.getVariable()
|
getAGuardedExpr(this.asExpr())
.getUnderlyingValue()
.(UndefinedNullCrashUse)
.getVulnerableSubexpression() = useVar and
// exclude types whose truthiness depend on the value
@@ -306,7 +309,6 @@ module Internal {
guardVar.getVariable() = useVar.getVariable()
|
getAGuardedExpr(guard)
.getUnderlyingValue()
.(UndefinedNullCrashUse)
.getVulnerableSubexpression() = useVar
)
@@ -375,7 +377,6 @@ module Internal {
guardVar.getVariable() = useVar.getVariable()
|
getAGuardedExpr(guard)
.getUnderlyingValue()
.(NonFunctionCallCrashUse)
.getVulnerableSubexpression() = useVar
) and