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Fix #14883 fuzzing crash (null-pointer-use) in Tokenizer::findGarbageCode() #8692

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Fix #14883 fuzzing crash (null-pointer-use) in Tokenizer::findGarbageCode() #8692

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157f79d
Update tokenize.cpp
chrchr-github Jul 3, 2026
e00e1f2
Create crash-17be2b85446aeb0c7722bedfad4b0e4af27fae3d
chrchr-github Jul 3, 2026
04e518d
Update tokenize.cpp
chrchr-github Jul 3, 2026
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2 changes: 2 additions & 0 deletions lib/tokenize.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -8962,6 +8962,8 @@ void Tokenizer::findGarbageCode() const
const Token* const endTok = tok->linkAt(1);
for (tok = tok->tokAt(2); tok != endTok; tok = tok->next()) {
if (const Token* lam = findLambdaEndTokenWithoutAST(tok)) {

@firewave firewave Jul 3, 2026

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If tok is nullptr this call would "fail" and thus we would still deref it below. IS this something to address or should we wait for fuzzed variant which will actually trigger that?

@chrchr-github chrchr-github Jul 3, 2026 •
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It should be fine for now since tok cannot be set to endTok anywhere else (findLambdaEndTokenWithoutAST() returns the Token after }).
precedes() cannot be used because token indices don't exist yet.

if (lam == endTok)
break;
tok = lam;
continue;
}
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1 change: 1 addition & 0 deletions test/cli/fuzz-crash/crash-17be2b85446aeb0c7722bedfad4b0e4af27fae3d
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@@ -0,0 +1 @@
{for([]{});}
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