#include "FuzzerInternal.h"
#include <sanitizer/coverage_interface.h>
#include <algorithm>
-#include <iostream>
+
+extern "C" {
+// Re-declare some of the sanitizer functions as "weak" so that
+// libFuzzer can be linked w/o the sanitizers and sanitizer-coveragte
+// (in which case it will complain at start-up time).
+__attribute__((weak)) void __sanitizer_print_stack_trace();
+__attribute__((weak)) size_t __sanitizer_get_total_unique_caller_callee_pairs();
+__attribute__((weak)) size_t __sanitizer_get_total_unique_coverage();
+__attribute__((weak))
+void __sanitizer_set_death_callback(void (*callback)(void));
+__attribute__((weak)) size_t __sanitizer_get_number_of_counters();
+__attribute__((weak))
+uintptr_t __sanitizer_update_counter_bitset_and_clear_counters(uint8_t *bitset);
+}
namespace fuzzer {
+static const size_t kMaxUnitSizeToPrint = 256;
+
+static void MissingWeakApiFunction(const char *FnName) {
+ Printf("ERROR: %s is not defined. Exiting.\n"
+ "Did you use -fsanitize-coverage=... to build your code?\n", FnName);
+ exit(1);
+}
-// static
-Unit Fuzzer::CurrentUnit;
-system_clock::time_point Fuzzer::UnitStartTime;
+#define CHECK_WEAK_API_FUNCTION(fn) \
+ do { \
+ if (!fn) \
+ MissingWeakApiFunction(#fn); \
+ } while (false)
+
+// Only one Fuzzer per process.
+static Fuzzer *F;
+
+Fuzzer::Fuzzer(UserSuppliedFuzzer &USF, FuzzingOptions Options)
+ : USF(USF), Options(Options) {
+ SetDeathCallback();
+ InitializeTraceState();
+ assert(!F);
+ F = this;
+}
void Fuzzer::SetDeathCallback() {
- __sanitizer_set_death_callback(DeathCallback);
+ CHECK_WEAK_API_FUNCTION(__sanitizer_set_death_callback);
+ __sanitizer_set_death_callback(StaticDeathCallback);
+}
+
+void Fuzzer::PrintUnitInASCII(const Unit &U, const char *PrintAfter) {
+ PrintASCII(U, PrintAfter);
+}
+
+void Fuzzer::StaticDeathCallback() {
+ assert(F);
+ F->DeathCallback();
}
void Fuzzer::DeathCallback() {
- std::cerr << "DEATH: " << std::endl;
- Print(CurrentUnit, "\n");
- PrintASCII(CurrentUnit, "\n");
- WriteToCrash(CurrentUnit, "crash-");
+ Printf("DEATH:\n");
+ if (CurrentUnit.size() <= kMaxUnitSizeToPrint) {
+ Print(CurrentUnit, "\n");
+ PrintUnitInASCII(CurrentUnit, "\n");
+ }
+ WriteUnitToFileWithPrefix(CurrentUnit, "crash-");
+}
+
+void Fuzzer::StaticAlarmCallback() {
+ assert(F);
+ F->AlarmCallback();
}
void Fuzzer::AlarmCallback() {
+ assert(Options.UnitTimeoutSec > 0);
size_t Seconds =
duration_cast<seconds>(system_clock::now() - UnitStartTime).count();
- std::cerr << "ALARM: working on the last Unit for " << Seconds << " seconds"
- << std::endl;
- if (Seconds >= 3) {
- Print(CurrentUnit, "\n");
- PrintASCII(CurrentUnit, "\n");
- WriteToCrash(CurrentUnit, "timeout-");
+ if (Seconds == 0) return;
+ if (Options.Verbosity >= 2)
+ Printf("AlarmCallback %zd\n", Seconds);
+ if (Seconds >= (size_t)Options.UnitTimeoutSec) {
+ Printf("ALARM: working on the last Unit for %zd seconds\n", Seconds);
+ Printf(" and the timeout value is %d (use -timeout=N to change)\n",
+ Options.UnitTimeoutSec);
+ if (CurrentUnit.size() <= kMaxUnitSizeToPrint) {
+ Print(CurrentUnit, "\n");
+ PrintUnitInASCII(CurrentUnit, "\n");
+ }
+ WriteUnitToFileWithPrefix(CurrentUnit, "timeout-");
+ Printf("==%d== ERROR: libFuzzer: timeout after %d seconds\n", GetPid(),
+ Seconds);
+ if (__sanitizer_print_stack_trace)
+ __sanitizer_print_stack_trace();
+ Printf("SUMMARY: libFuzzer: timeout\n");
+ exit(1);
+ }
+}
+
+void Fuzzer::PrintStats(const char *Where, const char *End) {
+ if (!Options.Verbosity) return;
+ size_t Seconds = secondsSinceProcessStartUp();
+ size_t ExecPerSec = (Seconds ? TotalNumberOfRuns / Seconds : 0);
+ Printf("#%zd\t%s", TotalNumberOfRuns, Where);
+ if (LastRecordedBlockCoverage)
+ Printf(" cov: %zd", LastRecordedBlockCoverage);
+ if (auto TB = TotalBits())
+ Printf(" bits: %zd", TB);
+ if (LastRecordedCallerCalleeCoverage)
+ Printf(" indir: %zd", LastRecordedCallerCalleeCoverage);
+ Printf(" units: %zd exec/s: %zd", Corpus.size(), ExecPerSec);
+ if (TotalNumberOfExecutedTraceBasedMutations)
+ Printf(" tbm: %zd", TotalNumberOfExecutedTraceBasedMutations);
+ Printf("%s", End);
+}
+
+void Fuzzer::RereadOutputCorpus() {
+ if (Options.OutputCorpus.empty()) return;
+ std::vector<Unit> AdditionalCorpus;
+ ReadDirToVectorOfUnits(Options.OutputCorpus.c_str(), &AdditionalCorpus,
+ &EpochOfLastReadOfOutputCorpus);
+ if (Corpus.empty()) {
+ Corpus = AdditionalCorpus;
+ return;
+ }
+ if (!Options.Reload) return;
+ if (Options.Verbosity >= 2)
+ Printf("Reload: read %zd new units.\n", AdditionalCorpus.size());
+ for (auto &X : AdditionalCorpus) {
+ if (X.size() > (size_t)Options.MaxLen)
+ X.resize(Options.MaxLen);
+ if (UnitHashesAddedToCorpus.insert(Hash(X)).second) {
+ CurrentUnit.clear();
+ CurrentUnit.insert(CurrentUnit.begin(), X.begin(), X.end());
+ if (RunOne(CurrentUnit)) {
+ Corpus.push_back(X);
+ if (Options.Verbosity >= 1)
+ PrintStats("RELOAD");
+ }
+ }
}
- exit(1);
}
void Fuzzer::ShuffleAndMinimize() {
- bool PreferSmall =
- (Options.PreferSmallDuringInitialShuffle == 1 ||
- (Options.PreferSmallDuringInitialShuffle == -1 && rand() % 2));
+ bool PreferSmall = (Options.PreferSmallDuringInitialShuffle == 1 ||
+ (Options.PreferSmallDuringInitialShuffle == -1 &&
+ USF.GetRand().RandBool()));
if (Options.Verbosity)
- std::cerr << "Shuffle: Size: " << Corpus.size()
- << " prefer small: " << PreferSmall
- << "\n";
+ Printf("PreferSmall: %d\n", PreferSmall);
+ PrintStats("READ ");
std::vector<Unit> NewCorpus;
- std::random_shuffle(Corpus.begin(), Corpus.end());
- if (PreferSmall)
- std::stable_sort(
- Corpus.begin(), Corpus.end(),
- [](const Unit &A, const Unit &B) { return A.size() < B.size(); });
- size_t MaxCov = 0;
+ if (Options.ShuffleAtStartUp) {
+ std::random_shuffle(Corpus.begin(), Corpus.end(), USF.GetRand());
+ if (PreferSmall)
+ std::stable_sort(
+ Corpus.begin(), Corpus.end(),
+ [](const Unit &A, const Unit &B) { return A.size() < B.size(); });
+ }
Unit &U = CurrentUnit;
for (const auto &C : Corpus) {
for (size_t First = 0; First < 1; First++) {
U.clear();
size_t Last = std::min(First + Options.MaxLen, C.size());
U.insert(U.begin(), C.begin() + First, C.begin() + Last);
- size_t NewCoverage = RunOne(U);
- if (NewCoverage) {
- MaxCov = NewCoverage;
+ if (Options.OnlyASCII)
+ ToASCII(U);
+ if (RunOne(U)) {
NewCorpus.push_back(U);
if (Options.Verbosity >= 2)
- std::cerr << "NEW0: " << NewCoverage
- << " L " << U.size()
- << "\n";
+ Printf("NEW0: %zd L %zd\n", LastRecordedBlockCoverage, U.size());
}
}
}
Corpus = NewCorpus;
- if (Options.Verbosity)
- std::cerr << "Shuffle done: " << Corpus.size() << " IC: " << MaxCov << "\n";
+ for (auto &X : Corpus)
+ UnitHashesAddedToCorpus.insert(Hash(X));
+ PrintStats("INITED");
}
-size_t Fuzzer::RunOne(const Unit &U) {
+bool Fuzzer::RunOne(const Unit &U) {
UnitStartTime = system_clock::now();
TotalNumberOfRuns++;
- if (Options.UseFullCoverageSet)
- return RunOneMaximizeFullCoverageSet(U);
- if (Options.UseCoveragePairs)
- return RunOneMaximizeCoveragePairs(U);
- return RunOneMaximizeTotalCoverage(U);
-}
-static uintptr_t HashOfArrayOfPCs(uintptr_t *PCs, uintptr_t NumPCs) {
- uintptr_t Res = 0;
- for (uintptr_t i = 0; i < NumPCs; i++) {
- Res = (Res + PCs[i]) * 7;
+ PrepareCoverageBeforeRun();
+ ExecuteCallback(U);
+ bool Res = CheckCoverageAfterRun();
+
+ auto UnitStopTime = system_clock::now();
+ auto TimeOfUnit =
+ duration_cast<seconds>(UnitStopTime - UnitStartTime).count();
+ if (!(TotalNumberOfRuns & (TotalNumberOfRuns - 1))
+ && secondsSinceProcessStartUp() >= 2
+ && Options.Verbosity)
+ PrintStats("pulse ");
+ if (TimeOfUnit > TimeOfLongestUnitInSeconds &&
+ TimeOfUnit >= Options.ReportSlowUnits) {
+ TimeOfLongestUnitInSeconds = TimeOfUnit;
+ Printf("Slowest unit: %zd s:\n", TimeOfLongestUnitInSeconds);
+ WriteUnitToFileWithPrefix(U, "slow-unit-");
}
return Res;
}
-// Experimental. Does not yet scale.
-// Fuly reset the current coverage state, run a single unit,
-// collect all coverage pairs and return non-zero if a new pair is observed.
-size_t Fuzzer::RunOneMaximizeCoveragePairs(const Unit &U) {
- __sanitizer_reset_coverage();
- Callback(U.data(), U.size());
- uintptr_t *PCs;
- uintptr_t NumPCs = __sanitizer_get_coverage_guards(&PCs);
- bool HasNewPairs = false;
- for (uintptr_t i = 0; i < NumPCs; i++) {
- if (!PCs[i]) continue;
- for (uintptr_t j = 0; j < NumPCs; j++) {
- if (!PCs[j]) continue;
- uint64_t Pair = (i << 32) | j;
- HasNewPairs |= CoveragePairs.insert(Pair).second;
- }
- }
- if (HasNewPairs)
- return CoveragePairs.size();
- return 0;
-}
-
-// Experimental.
-// Fuly reset the current coverage state, run a single unit,
-// compute a hash function from the full coverage set,
-// return non-zero if the hash value is new.
-// This produces tons of new units and as is it's only suitable for small tests,
-// e.g. test/FullCoverageSetTest.cpp. FIXME: make it scale.
-size_t Fuzzer::RunOneMaximizeFullCoverageSet(const Unit &U) {
- __sanitizer_reset_coverage();
- Callback(U.data(), U.size());
- uintptr_t *PCs;
- uintptr_t NumPCs =__sanitizer_get_coverage_guards(&PCs);
- if (FullCoverageSets.insert(HashOfArrayOfPCs(PCs, NumPCs)).second)
- return FullCoverageSets.size();
- return 0;
-}
-
-size_t Fuzzer::RunOneMaximizeTotalCoverage(const Unit &U) {
- size_t OldCoverage = __sanitizer_get_total_unique_coverage();
- Callback(U.data(), U.size());
- size_t NewCoverage = __sanitizer_get_total_unique_coverage();
- if (!(TotalNumberOfRuns & (TotalNumberOfRuns - 1)) && Options.Verbosity) {
- size_t Seconds = secondsSinceProcessStartUp();
- std::cerr
- << "#" << TotalNumberOfRuns
- << "\tcov: " << NewCoverage
- << "\texec/s: " << (Seconds ? TotalNumberOfRuns / Seconds : 0) << "\n";
+void Fuzzer::RunOneAndUpdateCorpus(Unit &U) {
+ if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
+ return;
+ if (Options.OnlyASCII)
+ ToASCII(U);
+ if (RunOne(U))
+ ReportNewCoverage(U);
+}
+
+void Fuzzer::ExecuteCallback(const Unit &U) {
+ int Res = USF.TargetFunction(U.data(), U.size());
+ (void)Res;
+ assert(Res == 0);
+}
+
+size_t Fuzzer::RecordBlockCoverage() {
+ CHECK_WEAK_API_FUNCTION(__sanitizer_get_total_unique_coverage);
+ return LastRecordedBlockCoverage = __sanitizer_get_total_unique_coverage();
+}
+
+size_t Fuzzer::RecordCallerCalleeCoverage() {
+ if (!Options.UseIndirCalls)
+ return 0;
+ if (!__sanitizer_get_total_unique_caller_callee_pairs)
+ return 0;
+ return LastRecordedCallerCalleeCoverage =
+ __sanitizer_get_total_unique_caller_callee_pairs();
+}
+
+void Fuzzer::PrepareCoverageBeforeRun() {
+ if (Options.UseCounters) {
+ size_t NumCounters = __sanitizer_get_number_of_counters();
+ CounterBitmap.resize(NumCounters);
+ __sanitizer_update_counter_bitset_and_clear_counters(0);
}
- if (NewCoverage > OldCoverage)
- return NewCoverage;
- return 0;
+ RecordBlockCoverage();
+ RecordCallerCalleeCoverage();
+}
+
+bool Fuzzer::CheckCoverageAfterRun() {
+ size_t OldCoverage = LastRecordedBlockCoverage;
+ size_t NewCoverage = RecordBlockCoverage();
+ size_t OldCallerCalleeCoverage = LastRecordedCallerCalleeCoverage;
+ size_t NewCallerCalleeCoverage = RecordCallerCalleeCoverage();
+ size_t NumNewBits = 0;
+ if (Options.UseCounters)
+ NumNewBits = __sanitizer_update_counter_bitset_and_clear_counters(
+ CounterBitmap.data());
+ return NewCoverage > OldCoverage ||
+ NewCallerCalleeCoverage > OldCallerCalleeCoverage || NumNewBits;
}
void Fuzzer::WriteToOutputCorpus(const Unit &U) {
std::string Path = DirPlusFile(Options.OutputCorpus, Hash(U));
WriteToFile(U, Path);
if (Options.Verbosity >= 2)
- std::cerr << "Written to " << Path << std::endl;
+ Printf("Written to %s\n", Path.c_str());
+ assert(!Options.OnlyASCII || IsASCII(U));
}
-void Fuzzer::WriteToCrash(const Unit &U, const char *Prefix) {
- std::string Path = Prefix + Hash(U);
+void Fuzzer::WriteUnitToFileWithPrefix(const Unit &U, const char *Prefix) {
+ if (!Options.SaveArtifacts)
+ return;
+ std::string Path = Options.ArtifactPrefix + Prefix + Hash(U);
WriteToFile(U, Path);
- std::cerr << "CRASHED; file written to " << Path << std::endl;
+ Printf("artifact_prefix='%s'; Test unit written to %s\n",
+ Options.ArtifactPrefix.c_str(), Path.c_str());
+ if (U.size() <= kMaxUnitSizeToPrint) {
+ Printf("Base64: ");
+ PrintFileAsBase64(Path);
+ }
}
void Fuzzer::SaveCorpus() {
for (const auto &U : Corpus)
WriteToFile(U, DirPlusFile(Options.OutputCorpus, Hash(U)));
if (Options.Verbosity)
- std::cerr << "Written corpus of " << Corpus.size() << " files to "
- << Options.OutputCorpus << "\n";
+ Printf("Written corpus of %zd files to %s\n", Corpus.size(),
+ Options.OutputCorpus.c_str());
+}
+
+void Fuzzer::ReportNewCoverage(const Unit &U) {
+ Corpus.push_back(U);
+ UnitHashesAddedToCorpus.insert(Hash(U));
+ PrintStats("NEW ", "");
+ if (Options.Verbosity) {
+ Printf(" L: %zd", U.size());
+ if (U.size() < 30) {
+ Printf(" ");
+ PrintUnitInASCII(U, "\t");
+ Print(U);
+ }
+ Printf("\n");
+ }
+ WriteToOutputCorpus(U);
+ if (Options.ExitOnFirst)
+ exit(0);
+}
+
+void Fuzzer::Merge(const std::vector<std::string> &Corpora) {
+ if (Corpora.size() <= 1) {
+ Printf("Merge requires two or more corpus dirs\n");
+ return;
+ }
+ auto InitialCorpusDir = Corpora[0];
+ ReadDir(InitialCorpusDir, nullptr);
+ Printf("Merge: running the initial corpus '%s' of %d units\n",
+ InitialCorpusDir.c_str(), Corpus.size());
+ for (auto &U : Corpus)
+ RunOne(U);
+
+ std::vector<std::string> ExtraCorpora(Corpora.begin() + 1, Corpora.end());
+
+ size_t NumTried = 0;
+ size_t NumMerged = 0;
+ for (auto &C : ExtraCorpora) {
+ Corpus.clear();
+ ReadDir(C, nullptr);
+ Printf("Merge: merging the extra corpus '%s' of %zd units\n", C.c_str(),
+ Corpus.size());
+ for (auto &U : Corpus) {
+ NumTried++;
+ if (RunOne(U)) {
+ WriteToOutputCorpus(U);
+ NumMerged++;
+ }
+ }
+ }
+ Printf("Merge: written %zd out of %zd units\n", NumMerged, NumTried);
}
-size_t Fuzzer::MutateAndTestOne(Unit *U) {
- size_t NewUnits = 0;
+void Fuzzer::MutateAndTestOne(Unit *U) {
for (int i = 0; i < Options.MutateDepth; i++) {
- if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
- return NewUnits;
- Mutate(U, Options.MaxLen);
- size_t NewCoverage = RunOne(*U);
- if (NewCoverage) {
- Corpus.push_back(*U);
- NewUnits++;
- if (Options.Verbosity) {
- std::cerr << "#" << TotalNumberOfRuns
- << "\tNEW: " << NewCoverage
- << " L: " << U->size()
- << " S: " << Corpus.size()
- << " I: " << i
- << "\t";
- if (U->size() < 30) {
- PrintASCII(*U);
- std::cerr << "\t";
- Print(*U);
- }
- std::cerr << "\n";
+ StartTraceRecording();
+ size_t Size = U->size();
+ U->resize(Options.MaxLen);
+ size_t NewSize = USF.Mutate(U->data(), Size, U->size());
+ assert(NewSize > 0 && "Mutator returned empty unit");
+ assert(NewSize <= (size_t)Options.MaxLen &&
+ "Mutator return overisized unit");
+ U->resize(NewSize);
+ RunOneAndUpdateCorpus(*U);
+ size_t NumTraceBasedMutations = StopTraceRecording();
+ size_t TBMWidth =
+ std::min((size_t)Options.TBMWidth, NumTraceBasedMutations);
+ size_t TBMDepth =
+ std::min((size_t)Options.TBMDepth, NumTraceBasedMutations);
+ Unit BackUp = *U;
+ for (size_t w = 0; w < TBMWidth; w++) {
+ *U = BackUp;
+ for (size_t d = 0; d < TBMDepth; d++) {
+ TotalNumberOfExecutedTraceBasedMutations++;
+ ApplyTraceBasedMutation(USF.GetRand()(NumTraceBasedMutations), U);
+ RunOneAndUpdateCorpus(*U);
}
- WriteToOutputCorpus(*U);
- if (Options.ExitOnFirst)
- exit(0);
}
}
- return NewUnits;
-}
-
-size_t Fuzzer::Loop(size_t NumIterations) {
- size_t NewUnits = 0;
- for (size_t i = 1; i <= NumIterations; i++) {
- for (size_t J1 = 0; J1 < Corpus.size(); J1++) {
- if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
- return NewUnits;
- // First, simply mutate the unit w/o doing crosses.
- CurrentUnit = Corpus[J1];
- NewUnits += MutateAndTestOne(&CurrentUnit);
- // Now, cross with others.
- if (Options.DoCrossOver) {
- for (size_t J2 = 0; J2 < Corpus.size(); J2++) {
- CurrentUnit.clear();
- CrossOver(Corpus[J1], Corpus[J2], &CurrentUnit, Options.MaxLen);
- NewUnits += MutateAndTestOne(&CurrentUnit);
- }
+}
+
+// Returns an index of random unit from the corpus to mutate.
+// Hypothesis: units added to the corpus last are more likely to be interesting.
+// This function gives more wieght to the more recent units.
+size_t Fuzzer::ChooseUnitToMutate() {
+ size_t N = Corpus.size();
+ size_t Total = (N + 1) * N / 2;
+ size_t R = USF.GetRand()(Total);
+ size_t IdxBeg = 0, IdxEnd = N;
+ // Binary search.
+ while (IdxEnd - IdxBeg >= 2) {
+ size_t Idx = IdxBeg + (IdxEnd - IdxBeg) / 2;
+ if (R > (Idx + 1) * Idx / 2)
+ IdxBeg = Idx;
+ else
+ IdxEnd = Idx;
+ }
+ assert(IdxBeg < N);
+ return IdxBeg;
+}
+
+void Fuzzer::Loop() {
+ for (auto &U: Options.Dictionary)
+ USF.GetMD().AddWordToDictionary(U.data(), U.size());
+
+ while (true) {
+ size_t J1 = ChooseUnitToMutate();;
+ SyncCorpus();
+ RereadOutputCorpus();
+ if (TotalNumberOfRuns >= Options.MaxNumberOfRuns)
+ return;
+ if (Options.MaxTotalTimeSec > 0 &&
+ secondsSinceProcessStartUp() >
+ static_cast<size_t>(Options.MaxTotalTimeSec))
+ return;
+ CurrentUnit = Corpus[J1];
+ // Optionally, cross with another unit.
+ if (Options.DoCrossOver && USF.GetRand().RandBool()) {
+ size_t J2 = ChooseUnitToMutate();
+ if (!Corpus[J1].empty() && !Corpus[J2].empty()) {
+ assert(!Corpus[J2].empty());
+ CurrentUnit.resize(Options.MaxLen);
+ size_t NewSize = USF.CrossOver(
+ Corpus[J1].data(), Corpus[J1].size(), Corpus[J2].data(),
+ Corpus[J2].size(), CurrentUnit.data(), CurrentUnit.size());
+ assert(NewSize > 0 && "CrossOver returned empty unit");
+ assert(NewSize <= (size_t)Options.MaxLen &&
+ "CrossOver returned overisized unit");
+ CurrentUnit.resize(NewSize);
}
}
+ // Perform several mutations and runs.
+ MutateAndTestOne(&CurrentUnit);
}
- return NewUnits;
+}
+
+void Fuzzer::SyncCorpus() {
+ if (Options.SyncCommand.empty() || Options.OutputCorpus.empty()) return;
+ auto Now = system_clock::now();
+ if (duration_cast<seconds>(Now - LastExternalSync).count() <
+ Options.SyncTimeout)
+ return;
+ LastExternalSync = Now;
+ ExecuteCommand(Options.SyncCommand + " " + Options.OutputCorpus);
}
} // namespace fuzzer
projects / oota-llvm.git / blobdiff