[libFuzzer] properly intercept memmem
llvm-svn: 276006
diff --git a/llvm/lib/Fuzzer/FuzzerTraceState.cpp b/llvm/lib/Fuzzer/FuzzerTraceState.cpp
index d6e1f79..6f87fca 100644
--- a/llvm/lib/Fuzzer/FuzzerTraceState.cpp
+++ b/llvm/lib/Fuzzer/FuzzerTraceState.cpp
@@ -173,6 +173,12 @@
static bool RecordingTraces = false;
static bool RecordingMemcmp = false;
static bool RecordingMemmem = false;
+static bool DoingMyOwnMemmem = false;
+
+struct ScopedDoingMyOwnMemmem {
+ ScopedDoingMyOwnMemmem() { DoingMyOwnMemmem = true; }
+ ~ScopedDoingMyOwnMemmem() { DoingMyOwnMemmem = false; }
+};
class TraceState {
public:
@@ -400,6 +406,7 @@
int TraceState::TryToAddDesiredData(uint64_t PresentData, uint64_t DesiredData,
size_t DataSize) {
if (NumMutations >= kMaxMutations || !WantToHandleOneMoreMutation()) return 0;
+ ScopedDoingMyOwnMemmem scoped_doing_my_own_memmem;
const uint8_t *UnitData;
auto UnitSize = F->GetCurrentUnitInFuzzingThead(&UnitData);
int Res = 0;
@@ -423,6 +430,7 @@
const uint8_t *DesiredData,
size_t DataSize) {
if (NumMutations >= kMaxMutations || !WantToHandleOneMoreMutation()) return 0;
+ ScopedDoingMyOwnMemmem scoped_doing_my_own_memmem;
const uint8_t *UnitData;
auto UnitSize = F->GetCurrentUnitInFuzzingThead(&UnitData);
int Res = 0;
@@ -639,7 +647,8 @@
}
void __sanitizer_weak_hook_memmem(void *called_pc, const void *s1, size_t len1,
const void *s2, size_t len2, void *result) {
- // TODO: can't hook memmem since memmem is used by libFuzzer.
+ if (fuzzer::DoingMyOwnMemmem) return;
+ TS->AddInterestingWord(reinterpret_cast<const uint8_t *>(s2), len2);
}
#endif // LLVM_FUZZER_DEFINES_SANITIZER_WEAK_HOOOKS