Exemplo n.º 1
0
// Tries detecting a memory leak on the particular input that we have just
// executed before calling this function.
void Fuzzer::TryDetectingAMemoryLeak(uint8_t *Data, size_t Size) {
  if (!HasMoreMallocsThanFrees) return;  // mallocs==frees, a leak is unlikely.
  if (!Options.DetectLeaks) return;
  if (!&__lsan_enable || !&__lsan_disable || !__lsan_do_recoverable_leak_check)
    return;  // No lsan.
  // Run the target once again, but with lsan disabled so that if there is
  // a real leak we do not report it twice.
  __lsan_disable();
  RunOneAndUpdateCorpus(Data, Size);
  __lsan_enable();
  if (!HasMoreMallocsThanFrees) return;  // a leak is unlikely.
  if (NumberOfLeakDetectionAttempts++ > 1000) {
    Options.DetectLeaks = false;
    Printf("INFO: libFuzzer disabled leak detection after every mutation.\n"
           "      Most likely the target function accumulates allocated\n"
           "      memory in a global state w/o actually leaking it.\n"
           "      If LeakSanitizer is enabled in this process it will still\n"
           "      run on the process shutdown.\n");
    return;
  }
  // Now perform the actual lsan pass. This is expensive and we must ensure
  // we don't call it too often.
  if (__lsan_do_recoverable_leak_check()) {  // Leak is found, report it.
    CurrentUnitData = Data;
    CurrentUnitSize = Size;
    DumpCurrentUnit("leak-");
    PrintFinalStats();
    _Exit(Options.ErrorExitCode);  // not exit() to disable lsan further on.
  }
}
Exemplo n.º 2
0
void key_destructor(void *arg) {
  __lsan_disable();
  void *p = malloc(1337);
  // Break optimization.
  fprintf(stderr, "Test alloc: %p.\n", p);
  pthread_setspecific(key, 0);
  __lsan_enable();
}
Exemplo n.º 3
0
int main() {
  void **p;
  {
    __lsan_disable();
    p = malloc(sizeof(void *));
    __lsan_enable();
  }
  *p = malloc(666);
  void *q = malloc(1337);
  // Break optimization.
  fprintf(stderr, "Test alloc: %p.\n", q);
  return 0;
}