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FuzzerDriver.cpp
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FuzzerDriver.cpp
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//===- FuzzerDriver.cpp - FuzzerDriver function and flags -----------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// FuzzerDriver and flag parsing.
//===----------------------------------------------------------------------===//
#include "FuzzerCommand.h"
#include "FuzzerCorpus.h"
#include "FuzzerFork.h"
#include "FuzzerIO.h"
#include "FuzzerInterface.h"
#include "FuzzerInternal.h"
#include "FuzzerMerge.h"
#include "FuzzerMutate.h"
#include "FuzzerPlatform.h"
#include "FuzzerRandom.h"
#include "FuzzerTracePC.h"
#include <algorithm>
#include <atomic>
#include <chrono>
#include <cstdlib>
#include <cstring>
#include <mutex>
#include <string>
#include <thread>
#include <fstream>
// This function should be present in the libFuzzer so that the client
// binary can test for its existence.
#if LIBFUZZER_MSVC
extern "C" void __libfuzzer_is_present() {}
#if defined(_M_IX86) || defined(__i386__)
#pragma comment(linker, "/include:___libfuzzer_is_present")
#else
#pragma comment(linker, "/include:__libfuzzer_is_present")
#endif
#else
extern "C" __attribute__((used)) void __libfuzzer_is_present() {}
#endif // LIBFUZZER_MSVC
namespace fuzzer {
// Program arguments.
struct FlagDescription {
const char *Name;
const char *Description;
int Default;
int *IntFlag;
const char **StrFlag;
unsigned int *UIntFlag;
};
struct {
#define FUZZER_DEPRECATED_FLAG(Name)
#define FUZZER_FLAG_INT(Name, Default, Description) int Name;
#define FUZZER_FLAG_UNSIGNED(Name, Default, Description) unsigned int Name;
#define FUZZER_FLAG_STRING(Name, Description) const char *Name;
#include "FuzzerFlags.def"
#undef FUZZER_DEPRECATED_FLAG
#undef FUZZER_FLAG_INT
#undef FUZZER_FLAG_UNSIGNED
#undef FUZZER_FLAG_STRING
} Flags;
static const FlagDescription FlagDescriptions [] {
#define FUZZER_DEPRECATED_FLAG(Name) \
{#Name, "Deprecated; don't use", 0, nullptr, nullptr, nullptr},
#define FUZZER_FLAG_INT(Name, Default, Description) \
{#Name, Description, Default, &Flags.Name, nullptr, nullptr},
#define FUZZER_FLAG_UNSIGNED(Name, Default, Description) \
{#Name, Description, static_cast<int>(Default), \
nullptr, nullptr, &Flags.Name},
#define FUZZER_FLAG_STRING(Name, Description) \
{#Name, Description, 0, nullptr, &Flags.Name, nullptr},
#include "FuzzerFlags.def"
#undef FUZZER_DEPRECATED_FLAG
#undef FUZZER_FLAG_INT
#undef FUZZER_FLAG_UNSIGNED
#undef FUZZER_FLAG_STRING
};
static const size_t kNumFlags =
sizeof(FlagDescriptions) / sizeof(FlagDescriptions[0]);
static Vector<std::string> *Inputs;
static std::string *ProgName;
static void PrintHelp() {
Printf("Usage:\n");
auto Prog = ProgName->c_str();
Printf("\nTo run fuzzing pass 0 or more directories.\n");
Printf("%s [-flag1=val1 [-flag2=val2 ...] ] [dir1 [dir2 ...] ]\n", Prog);
Printf("\nTo run individual tests without fuzzing pass 1 or more files:\n");
Printf("%s [-flag1=val1 [-flag2=val2 ...] ] file1 [file2 ...]\n", Prog);
Printf("\nFlags: (strictly in form -flag=value)\n");
size_t MaxFlagLen = 0;
for (size_t F = 0; F < kNumFlags; F++)
MaxFlagLen = std::max(strlen(FlagDescriptions[F].Name), MaxFlagLen);
for (size_t F = 0; F < kNumFlags; F++) {
const auto &D = FlagDescriptions[F];
if (strstr(D.Description, "internal flag") == D.Description) continue;
Printf(" %s", D.Name);
for (size_t i = 0, n = MaxFlagLen - strlen(D.Name); i < n; i++)
Printf(" ");
Printf("\t");
Printf("%d\t%s\n", D.Default, D.Description);
}
Printf("\nFlags starting with '--' will be ignored and "
"will be passed verbatim to subprocesses.\n");
}
static const char *FlagValue(const char *Param, const char *Name) {
size_t Len = strlen(Name);
if (Param[0] == '-' && strstr(Param + 1, Name) == Param + 1 &&
Param[Len + 1] == '=')
return &Param[Len + 2];
return nullptr;
}
// Avoid calling stol as it triggers a bug in clang/glibc build.
static long MyStol(const char *Str) {
long Res = 0;
long Sign = 1;
if (*Str == '-') {
Str++;
Sign = -1;
}
for (size_t i = 0; Str[i]; i++) {
char Ch = Str[i];
if (Ch < '0' || Ch > '9')
return Res;
Res = Res * 10 + (Ch - '0');
}
return Res * Sign;
}
static bool ParseOneFlag(const char *Param) {
if (Param[0] != '-') return false;
if (Param[1] == '-') {
static bool PrintedWarning = false;
if (!PrintedWarning) {
PrintedWarning = true;
Printf("INFO: libFuzzer ignores flags that start with '--'\n");
}
for (size_t F = 0; F < kNumFlags; F++)
if (FlagValue(Param + 1, FlagDescriptions[F].Name))
Printf("WARNING: did you mean '%s' (single dash)?\n", Param + 1);
return true;
}
for (size_t F = 0; F < kNumFlags; F++) {
const char *Name = FlagDescriptions[F].Name;
const char *Str = FlagValue(Param, Name);
if (Str) {
if (FlagDescriptions[F].IntFlag) {
int Val = MyStol(Str);
*FlagDescriptions[F].IntFlag = Val;
if (Flags.verbosity >= 2)
Printf("Flag: %s %d\n", Name, Val);
return true;
} else if (FlagDescriptions[F].UIntFlag) {
unsigned int Val = std::stoul(Str);
*FlagDescriptions[F].UIntFlag = Val;
if (Flags.verbosity >= 2)
Printf("Flag: %s %u\n", Name, Val);
return true;
} else if (FlagDescriptions[F].StrFlag) {
*FlagDescriptions[F].StrFlag = Str;
if (Flags.verbosity >= 2)
Printf("Flag: %s %s\n", Name, Str);
return true;
} else { // Deprecated flag.
Printf("Flag: %s: deprecated, don't use\n", Name);
return true;
}
}
}
Printf("\n\nWARNING: unrecognized flag '%s'; "
"use -help=1 to list all flags\n\n", Param);
return true;
}
// We don't use any library to minimize dependencies.
static void ParseFlags(const Vector<std::string> &Args,
const ExternalFunctions *EF) {
for (size_t F = 0; F < kNumFlags; F++) {
if (FlagDescriptions[F].IntFlag)
*FlagDescriptions[F].IntFlag = FlagDescriptions[F].Default;
if (FlagDescriptions[F].UIntFlag)
*FlagDescriptions[F].UIntFlag =
static_cast<unsigned int>(FlagDescriptions[F].Default);
if (FlagDescriptions[F].StrFlag)
*FlagDescriptions[F].StrFlag = nullptr;
}
// Disable len_control by default, if LLVMFuzzerCustomMutator is used.
if (EF->LLVMFuzzerCustomMutator) {
Flags.len_control = 0;
Printf("INFO: found LLVMFuzzerCustomMutator (%p). "
"Disabling -len_control by default.\n", EF->LLVMFuzzerCustomMutator);
}
Inputs = new Vector<std::string>;
for (size_t A = 1; A < Args.size(); A++) {
if (ParseOneFlag(Args[A].c_str())) {
if (Flags.ignore_remaining_args)
break;
continue;
}
Inputs->push_back(Args[A]);
}
}
static std::mutex Mu;
static void PulseThread() {
while (true) {
SleepSeconds(600);
std::lock_guard<std::mutex> Lock(Mu);
Printf("pulse...\n");
}
}
static void WorkerThread(const Command &BaseCmd, std::atomic<unsigned> *Counter,
unsigned NumJobs, std::atomic<bool> *HasErrors) {
while (true) {
unsigned C = (*Counter)++;
if (C >= NumJobs) break;
std::string Log = "fuzz-" + std::to_string(C) + ".log";
Command Cmd(BaseCmd);
Cmd.setOutputFile(Log);
Cmd.combineOutAndErr();
if (Flags.verbosity) {
std::string CommandLine = Cmd.toString();
Printf("%s\n", CommandLine.c_str());
}
int ExitCode = ExecuteCommand(Cmd);
if (ExitCode != 0)
*HasErrors = true;
std::lock_guard<std::mutex> Lock(Mu);
Printf("================== Job %u exited with exit code %d ============\n",
C, ExitCode);
fuzzer::CopyFileToErr(Log);
}
}
static void ValidateDirectoryExists(const std::string &Path,
bool CreateDirectory) {
if (Path.empty()) {
Printf("ERROR: Provided directory path is an empty string\n");
exit(1);
}
if (IsDirectory(Path))
return;
if (CreateDirectory) {
if (!MkDirRecursive(Path)) {
Printf("ERROR: Failed to create directory \"%s\"\n", Path.c_str());
exit(1);
}
return;
}
Printf("ERROR: The required directory \"%s\" does not exist\n", Path.c_str());
exit(1);
}
std::string CloneArgsWithoutX(const Vector<std::string> &Args,
const char *X1, const char *X2) {
std::string Cmd;
for (auto &S : Args) {
if (FlagValue(S.c_str(), X1) || FlagValue(S.c_str(), X2))
continue;
Cmd += S + " ";
}
return Cmd;
}
static int RunInMultipleProcesses(const Vector<std::string> &Args,
unsigned NumWorkers, unsigned NumJobs) {
std::atomic<unsigned> Counter(0);
std::atomic<bool> HasErrors(false);
Command Cmd(Args);
Cmd.removeFlag("jobs");
Cmd.removeFlag("workers");
Vector<std::thread> V;
std::thread Pulse(PulseThread);
Pulse.detach();
for (unsigned i = 0; i < NumWorkers; i++)
V.push_back(std::thread(WorkerThread, std::ref(Cmd), &Counter, NumJobs, &HasErrors));
for (auto &T : V)
T.join();
return HasErrors ? 1 : 0;
}
static void RssThread(Fuzzer *F, size_t RssLimitMb) {
while (true) {
SleepSeconds(1);
size_t Peak = GetPeakRSSMb();
if (Peak > RssLimitMb)
F->RssLimitCallback();
}
}
static void StartRssThread(Fuzzer *F, size_t RssLimitMb) {
if (!RssLimitMb)
return;
std::thread T(RssThread, F, RssLimitMb);
T.detach();
}
int RunOneTest(Fuzzer *F, const char *InputFilePath, size_t MaxLen) {
Unit U = FileToVector(InputFilePath);
if (MaxLen && MaxLen < U.size())
U.resize(MaxLen);
F->ExecuteCallback(U.data(), U.size());
if (Flags.print_full_coverage) {
// Leak detection is not needed when collecting full coverage data.
F->TPCUpdateObservedPCs();
} else {
F->TryDetectingAMemoryLeak(U.data(), U.size(), true);
}
return 0;
}
static bool AllInputsAreFiles() {
if (Inputs->empty()) return false;
for (auto &Path : *Inputs)
if (!IsFile(Path))
return false;
return true;
}
static std::string GetDedupTokenFromCmdOutput(const std::string &S) {
auto Beg = S.find("DEDUP_TOKEN:");
if (Beg == std::string::npos)
return "";
auto End = S.find('\n', Beg);
if (End == std::string::npos)
return "";
return S.substr(Beg, End - Beg);
}
int CleanseCrashInput(const Vector<std::string> &Args,
const FuzzingOptions &Options) {
if (Inputs->size() != 1 || !Flags.exact_artifact_path) {
Printf("ERROR: -cleanse_crash should be given one input file and"
" -exact_artifact_path\n");
exit(1);
}
std::string InputFilePath = Inputs->at(0);
std::string OutputFilePath = Flags.exact_artifact_path;
Command Cmd(Args);
Cmd.removeFlag("cleanse_crash");
assert(Cmd.hasArgument(InputFilePath));
Cmd.removeArgument(InputFilePath);
auto TmpFilePath = TempPath("CleanseCrashInput", ".repro");
Cmd.addArgument(TmpFilePath);
Cmd.setOutputFile(getDevNull());
Cmd.combineOutAndErr();
std::string CurrentFilePath = InputFilePath;
auto U = FileToVector(CurrentFilePath);
size_t Size = U.size();
const Vector<uint8_t> ReplacementBytes = {' ', 0xff};
for (int NumAttempts = 0; NumAttempts < 5; NumAttempts++) {
bool Changed = false;
for (size_t Idx = 0; Idx < Size; Idx++) {
Printf("CLEANSE[%d]: Trying to replace byte %zd of %zd\n", NumAttempts,
Idx, Size);
uint8_t OriginalByte = U[Idx];
if (ReplacementBytes.end() != std::find(ReplacementBytes.begin(),
ReplacementBytes.end(),
OriginalByte))
continue;
for (auto NewByte : ReplacementBytes) {
U[Idx] = NewByte;
WriteToFile(U, TmpFilePath);
auto ExitCode = ExecuteCommand(Cmd);
RemoveFile(TmpFilePath);
if (!ExitCode) {
U[Idx] = OriginalByte;
} else {
Changed = true;
Printf("CLEANSE: Replaced byte %zd with 0x%x\n", Idx, NewByte);
WriteToFile(U, OutputFilePath);
break;
}
}
}
if (!Changed) break;
}
return 0;
}
int MinimizeCrashInput(const Vector<std::string> &Args,
const FuzzingOptions &Options) {
if (Inputs->size() != 1) {
Printf("ERROR: -minimize_crash should be given one input file\n");
exit(1);
}
std::string InputFilePath = Inputs->at(0);
Command BaseCmd(Args);
BaseCmd.removeFlag("minimize_crash");
BaseCmd.removeFlag("exact_artifact_path");
assert(BaseCmd.hasArgument(InputFilePath));
BaseCmd.removeArgument(InputFilePath);
if (Flags.runs <= 0 && Flags.max_total_time == 0) {
Printf("INFO: you need to specify -runs=N or "
"-max_total_time=N with -minimize_crash=1\n"
"INFO: defaulting to -max_total_time=600\n");
BaseCmd.addFlag("max_total_time", "600");
}
BaseCmd.combineOutAndErr();
std::string CurrentFilePath = InputFilePath;
while (true) {
Unit U = FileToVector(CurrentFilePath);
Printf("CRASH_MIN: minimizing crash input: '%s' (%zd bytes)\n",
CurrentFilePath.c_str(), U.size());
Command Cmd(BaseCmd);
Cmd.addArgument(CurrentFilePath);
Printf("CRASH_MIN: executing: %s\n", Cmd.toString().c_str());
std::string CmdOutput;
bool Success = ExecuteCommand(Cmd, &CmdOutput);
if (Success) {
Printf("ERROR: the input %s did not crash\n", CurrentFilePath.c_str());
exit(1);
}
Printf("CRASH_MIN: '%s' (%zd bytes) caused a crash. Will try to minimize "
"it further\n",
CurrentFilePath.c_str(), U.size());
auto DedupToken1 = GetDedupTokenFromCmdOutput(CmdOutput);
if (!DedupToken1.empty())
Printf("CRASH_MIN: DedupToken1: %s\n", DedupToken1.c_str());
std::string ArtifactPath =
Flags.exact_artifact_path
? Flags.exact_artifact_path
: Options.ArtifactPrefix + "minimized-from-" + Hash(U);
Cmd.addFlag("minimize_crash_internal_step", "1");
Cmd.addFlag("exact_artifact_path", ArtifactPath);
Printf("CRASH_MIN: executing: %s\n", Cmd.toString().c_str());
CmdOutput.clear();
Success = ExecuteCommand(Cmd, &CmdOutput);
Printf("%s", CmdOutput.c_str());
if (Success) {
if (Flags.exact_artifact_path) {
CurrentFilePath = Flags.exact_artifact_path;
WriteToFile(U, CurrentFilePath);
}
Printf("CRASH_MIN: failed to minimize beyond %s (%d bytes), exiting\n",
CurrentFilePath.c_str(), U.size());
break;
}
auto DedupToken2 = GetDedupTokenFromCmdOutput(CmdOutput);
if (!DedupToken2.empty())
Printf("CRASH_MIN: DedupToken2: %s\n", DedupToken2.c_str());
if (DedupToken1 != DedupToken2) {
if (Flags.exact_artifact_path) {
CurrentFilePath = Flags.exact_artifact_path;
WriteToFile(U, CurrentFilePath);
}
Printf("CRASH_MIN: mismatch in dedup tokens"
" (looks like a different bug). Won't minimize further\n");
break;
}
CurrentFilePath = ArtifactPath;
Printf("*********************************\n");
}
return 0;
}
int MinimizeCrashInputInternalStep(Fuzzer *F, InputCorpus *Corpus) {
assert(Inputs->size() == 1);
std::string InputFilePath = Inputs->at(0);
Unit U = FileToVector(InputFilePath);
Printf("INFO: Starting MinimizeCrashInputInternalStep: %zd\n", U.size());
if (U.size() < 2) {
Printf("INFO: The input is small enough, exiting\n");
exit(0);
}
F->SetMaxInputLen(U.size());
F->SetMaxMutationLen(U.size() - 1);
F->MinimizeCrashLoop(U);
Printf("INFO: Done MinimizeCrashInputInternalStep, no crashes found\n");
exit(0);
return 0;
}
void Merge(Fuzzer *F, FuzzingOptions &Options, const Vector<std::string> &Args,
const Vector<std::string> &Corpora, const char *CFPathOrNull) {
if (Corpora.size() < 2) {
Printf("INFO: Merge requires two or more corpus dirs\n");
exit(0);
}
Vector<SizedFile> OldCorpus, NewCorpus;
GetSizedFilesFromDir(Corpora[0], &OldCorpus);
for (size_t i = 1; i < Corpora.size(); i++)
GetSizedFilesFromDir(Corpora[i], &NewCorpus);
std::sort(OldCorpus.begin(), OldCorpus.end());
std::sort(NewCorpus.begin(), NewCorpus.end());
std::string CFPath = CFPathOrNull ? CFPathOrNull : TempPath("Merge", ".txt");
Vector<std::string> NewFiles;
Set<uint32_t> NewFeatures, NewCov;
CrashResistantMerge(Args, OldCorpus, NewCorpus, &NewFiles, {}, &NewFeatures,
{}, &NewCov, CFPath, true);
for (auto &Path : NewFiles)
F->WriteToOutputCorpus(FileToVector(Path, Options.MaxLen));
// We are done, delete the control file if it was a temporary one.
if (!Flags.merge_control_file)
RemoveFile(CFPath);
exit(0);
}
int AnalyzeDictionary(Fuzzer *F, const Vector<Unit>& Dict,
UnitVector& Corpus) {
Printf("Started dictionary minimization (up to %d tests)\n",
Dict.size() * Corpus.size() * 2);
// Scores and usage count for each dictionary unit.
Vector<int> Scores(Dict.size());
Vector<int> Usages(Dict.size());
Vector<size_t> InitialFeatures;
Vector<size_t> ModifiedFeatures;
for (auto &C : Corpus) {
// Get coverage for the testcase without modifications.
F->ExecuteCallback(C.data(), C.size());
InitialFeatures.clear();
TPC.CollectFeatures([&](size_t Feature) {
InitialFeatures.push_back(Feature);
});
for (size_t i = 0; i < Dict.size(); ++i) {
Vector<uint8_t> Data = C;
auto StartPos = std::search(Data.begin(), Data.end(),
Dict[i].begin(), Dict[i].end());
// Skip dictionary unit, if the testcase does not contain it.
if (StartPos == Data.end())
continue;
++Usages[i];
while (StartPos != Data.end()) {
// Replace all occurrences of dictionary unit in the testcase.
auto EndPos = StartPos + Dict[i].size();
for (auto It = StartPos; It != EndPos; ++It)
*It ^= 0xFF;
StartPos = std::search(EndPos, Data.end(),
Dict[i].begin(), Dict[i].end());
}
// Get coverage for testcase with masked occurrences of dictionary unit.
F->ExecuteCallback(Data.data(), Data.size());
ModifiedFeatures.clear();
TPC.CollectFeatures([&](size_t Feature) {
ModifiedFeatures.push_back(Feature);
});
if (InitialFeatures == ModifiedFeatures)
--Scores[i];
else
Scores[i] += 2;
}
}
Printf("###### Useless dictionary elements. ######\n");
for (size_t i = 0; i < Dict.size(); ++i) {
// Dictionary units with positive score are treated as useful ones.
if (Scores[i] > 0)
continue;
Printf("\"");
PrintASCII(Dict[i].data(), Dict[i].size(), "\"");
Printf(" # Score: %d, Used: %d\n", Scores[i], Usages[i]);
}
Printf("###### End of useless dictionary elements. ######\n");
return 0;
}
Vector<std::string> ParseSeedInuts(const char *seed_inputs) {
// Parse -seed_inputs=file1,file2,... or -seed_inputs=@seed_inputs_file
Vector<std::string> Files;
if (!seed_inputs) return Files;
std::string SeedInputs;
if (Flags.seed_inputs[0] == '@')
SeedInputs = FileToString(Flags.seed_inputs + 1); // File contains list.
else
SeedInputs = Flags.seed_inputs; // seed_inputs contains the list.
if (SeedInputs.empty()) {
Printf("seed_inputs is empty or @file does not exist.\n");
exit(1);
}
// Parse SeedInputs.
size_t comma_pos = 0;
while ((comma_pos = SeedInputs.find_last_of(',')) != std::string::npos) {
Files.push_back(SeedInputs.substr(comma_pos + 1));
SeedInputs = SeedInputs.substr(0, comma_pos);
}
Files.push_back(SeedInputs);
return Files;
}
static Vector<SizedFile> ReadCorpora(const Vector<std::string> &CorpusDirs,
const Vector<std::string> &ExtraSeedFiles) {
Vector<SizedFile> SizedFiles;
size_t LastNumFiles = 0;
for (auto &Dir : CorpusDirs) {
GetSizedFilesFromDir(Dir, &SizedFiles);
Printf("INFO: % 8zd files found in %s\n", SizedFiles.size() - LastNumFiles,
Dir.c_str());
LastNumFiles = SizedFiles.size();
}
for (auto &File : ExtraSeedFiles)
if (auto Size = FileSize(File))
SizedFiles.push_back({File, Size});
return SizedFiles;
}
int FuzzerDriver(int *argc, char ***argv, UserCallback Callback) {
using namespace fuzzer;
assert(argc && argv && "Argument pointers cannot be nullptr");
std::string Argv0((*argv)[0]);
EF = new ExternalFunctions();
if (EF->LLVMFuzzerInitialize)
EF->LLVMFuzzerInitialize(argc, argv);
if (EF->__msan_scoped_disable_interceptor_checks)
EF->__msan_scoped_disable_interceptor_checks();
const Vector<std::string> Args(*argv, *argv + *argc);
assert(!Args.empty());
ProgName = new std::string(Args[0]);
if (Argv0 != *ProgName) {
Printf("ERROR: argv[0] has been modified in LLVMFuzzerInitialize\n");
exit(1);
}
ParseFlags(Args, EF);
if (Flags.help) {
PrintHelp();
return 0;
}
if (Flags.close_fd_mask & 2)
DupAndCloseStderr();
if (Flags.close_fd_mask & 1)
CloseStdout();
if (Flags.jobs > 0 && Flags.workers == 0) {
Flags.workers = std::min(NumberOfCpuCores() / 2, Flags.jobs);
if (Flags.workers > 1)
Printf("Running %u workers\n", Flags.workers);
}
if (Flags.workers > 0 && Flags.jobs > 0)
return RunInMultipleProcesses(Args, Flags.workers, Flags.jobs);
FuzzingOptions Options;
Options.Verbosity = Flags.verbosity;
Options.MaxLen = Flags.max_len;
Options.LenControl = Flags.len_control;
Options.KeepSeed = Flags.keep_seed;
Options.UnitTimeoutSec = Flags.timeout;
Options.ErrorExitCode = Flags.error_exitcode;
Options.TimeoutExitCode = Flags.timeout_exitcode;
Options.IgnoreTimeouts = Flags.ignore_timeouts;
Options.IgnoreOOMs = Flags.ignore_ooms;
Options.IgnoreCrashes = Flags.ignore_crashes;
Options.MaxTotalTimeSec = Flags.max_total_time;
Options.DoCrossOver = Flags.cross_over;
Options.CrossOverUniformDist = Flags.cross_over_uniform_dist;
Options.MutateDepth = Flags.mutate_depth;
Options.ReduceDepth = Flags.reduce_depth;
Options.UseCounters = Flags.use_counters;
Options.UseMemmem = Flags.use_memmem;
Options.UseCmp = Flags.use_cmp;
Options.UseValueProfile = Flags.use_value_profile;
Options.Shrink = Flags.shrink;
Options.ReduceInputs = Flags.reduce_inputs;
Options.ShuffleAtStartUp = Flags.shuffle;
Options.PreferSmall = Flags.prefer_small;
Options.ReloadIntervalSec = Flags.reload;
Options.OnlyASCII = Flags.only_ascii;
Options.DetectLeaks = Flags.detect_leaks;
Options.PurgeAllocatorIntervalSec = Flags.purge_allocator_interval;
Options.TraceMalloc = Flags.trace_malloc;
Options.RssLimitMb = Flags.rss_limit_mb;
Options.MallocLimitMb = Flags.malloc_limit_mb;
if (!Options.MallocLimitMb)
Options.MallocLimitMb = Options.RssLimitMb;
if (Flags.runs >= 0)
Options.MaxNumberOfRuns = Flags.runs;
if (!Inputs->empty() && !Flags.minimize_crash_internal_step) {
// Ensure output corpus assumed to be the first arbitrary argument input
// is not a path to an existing file.
std::string OutputCorpusDir = (*Inputs)[0];
if (!IsFile(OutputCorpusDir)) {
Options.OutputCorpus = OutputCorpusDir;
ValidateDirectoryExists(Options.OutputCorpus, Flags.create_missing_dirs);
}
}
Options.ReportSlowUnits = Flags.report_slow_units;
if (Flags.artifact_prefix) {
Options.ArtifactPrefix = Flags.artifact_prefix;
// Since the prefix could be a full path to a file name prefix, assume
// that if the path ends with the platform's separator that a directory
// is desired
std::string ArtifactPathDir = Options.ArtifactPrefix;
if (!IsSeparator(ArtifactPathDir[ArtifactPathDir.length() - 1])) {
ArtifactPathDir = DirName(ArtifactPathDir);
}
ValidateDirectoryExists(ArtifactPathDir, Flags.create_missing_dirs);
}
if (Flags.exact_artifact_path) {
Options.ExactArtifactPath = Flags.exact_artifact_path;
ValidateDirectoryExists(DirName(Options.ExactArtifactPath),
Flags.create_missing_dirs);
}
Vector<Unit> Dictionary;
if (Flags.dict)
if (!ParseDictionaryFile(FileToString(Flags.dict), &Dictionary))
return 1;
if (Flags.verbosity > 0 && !Dictionary.empty())
Printf("Dictionary: %zd entries\n", Dictionary.size());
bool RunIndividualFiles = AllInputsAreFiles();
Options.SaveArtifacts =
!RunIndividualFiles || Flags.minimize_crash_internal_step;
Options.PrintNewCovPcs = Flags.print_pcs;
Options.PrintNewCovFuncs = Flags.print_funcs;
Options.PrintFinalStats = Flags.print_final_stats;
Options.PrintCorpusStats = Flags.print_corpus_stats;
Options.PrintCoverage = Flags.print_coverage;
Options.PrintFullCoverage = Flags.print_full_coverage;
if (Flags.exit_on_src_pos)
Options.ExitOnSrcPos = Flags.exit_on_src_pos;
if (Flags.exit_on_item)
Options.ExitOnItem = Flags.exit_on_item;
if (Flags.focus_function)
Options.FocusFunction = Flags.focus_function;
if (Flags.data_flow_trace)
Options.DataFlowTrace = Flags.data_flow_trace;
if (Flags.features_dir) {
Options.FeaturesDir = Flags.features_dir;
ValidateDirectoryExists(Options.FeaturesDir, Flags.create_missing_dirs);
}
if (Flags.mutation_graph_file)
Options.MutationGraphFile = Flags.mutation_graph_file;
if (Flags.collect_data_flow)
Options.CollectDataFlow = Flags.collect_data_flow;
if (Flags.stop_file)
Options.StopFile = Flags.stop_file;
Options.Entropic = Flags.entropic;
Options.EntropicFeatureFrequencyThreshold =
(size_t)Flags.entropic_feature_frequency_threshold;
Options.EntropicNumberOfRarestFeatures =
(size_t)Flags.entropic_number_of_rarest_features;
Options.EntropicScalePerExecTime = Flags.entropic_scale_per_exec_time;
if (!Options.FocusFunction.empty())
Options.Entropic = false; // FocusFunction overrides entropic scheduling.
if (Options.Entropic)
Printf("INFO: Running with entropic power schedule (0x%X, %d).\n",
Options.EntropicFeatureFrequencyThreshold,
Options.EntropicNumberOfRarestFeatures);
struct EntropicOptions Entropic;
Entropic.Enabled = Options.Entropic;
Entropic.FeatureFrequencyThreshold =
Options.EntropicFeatureFrequencyThreshold;
Entropic.NumberOfRarestFeatures = Options.EntropicNumberOfRarestFeatures;
Entropic.ScalePerExecTime = Options.EntropicScalePerExecTime;
unsigned Seed = Flags.seed;
// Initialize Seed.
if (Seed == 0)
Seed =
std::chrono::system_clock::now().time_since_epoch().count() + GetPid();
if (Flags.verbosity)
Printf("INFO: Seed: %u\n", Seed);
if (Flags.collect_data_flow && !Flags.fork && !Flags.merge) {
if (RunIndividualFiles)
return CollectDataFlow(Flags.collect_data_flow, Flags.data_flow_trace,
ReadCorpora({}, *Inputs));
else
return CollectDataFlow(Flags.collect_data_flow, Flags.data_flow_trace,
ReadCorpora(*Inputs, {}));
}
Random Rand(Seed);
auto *MD = new MutationDispatcher(Rand, Options);
auto *Corpus = new InputCorpus(Options.OutputCorpus, Entropic);
auto *F = new Fuzzer(Callback, *Corpus, *MD, Options);
for (auto &U: Dictionary)
if (U.size() <= Word::GetMaxSize())
MD->AddWordToManualDictionary(Word(U.data(), U.size()));
// Threads are only supported by Chrome. Don't use them with emscripten
// for now.
#if !LIBFUZZER_EMSCRIPTEN
StartRssThread(F, Flags.rss_limit_mb);
#endif // LIBFUZZER_EMSCRIPTEN
Options.HandleAbrt = Flags.handle_abrt;
Options.HandleAlrm = !Flags.minimize_crash;
Options.HandleBus = Flags.handle_bus;
Options.HandleFpe = Flags.handle_fpe;
Options.HandleIll = Flags.handle_ill;
Options.HandleInt = Flags.handle_int;
Options.HandleSegv = Flags.handle_segv;
Options.HandleTerm = Flags.handle_term;
Options.HandleXfsz = Flags.handle_xfsz;
Options.HandleUsr1 = Flags.handle_usr1;
Options.HandleUsr2 = Flags.handle_usr2;
Options.HandleWinExcept = Flags.handle_winexcept;
SetSignalHandler(Options);
std::atexit(Fuzzer::StaticExitCallback);
if (Flags.minimize_crash)
return MinimizeCrashInput(Args, Options);
if (Flags.minimize_crash_internal_step)
return MinimizeCrashInputInternalStep(F, Corpus);
if (Flags.cleanse_crash)
return CleanseCrashInput(Args, Options);
if (RunIndividualFiles) {
Options.SaveArtifacts = false;
int Runs = std::max(1, Flags.runs);
Printf("%s: Running %zd inputs %d time(s) each.\n", ProgName->c_str(),
Inputs->size(), Runs);
for (auto &Path : *Inputs) {
auto StartTime = system_clock::now();
Printf("Running: %s\n", Path.c_str());
for (int Iter = 0; Iter < Runs; Iter++)
RunOneTest(F, Path.c_str(), Options.MaxLen);
auto StopTime = system_clock::now();
auto MS = duration_cast<milliseconds>(StopTime - StartTime).count();
Printf("Executed %s in %zd ms\n", Path.c_str(), (long)MS);
}
Printf("***\n"
"*** NOTE: fuzzing was not performed, you have only\n"
"*** executed the target code on a fixed set of inputs.\n"
"***\n");
F->PrintFinalStats();
exit(0);
}
if (Flags.fork)
FuzzWithFork(F->GetMD().GetRand(), Options, Args, *Inputs, Flags.fork);
if (Flags.merge)
Merge(F, Options, Args, *Inputs, Flags.merge_control_file);
if (Flags.merge_inner) {
const size_t kDefaultMaxMergeLen = 1 << 20;
if (Options.MaxLen == 0)
F->SetMaxInputLen(kDefaultMaxMergeLen);
assert(Flags.merge_control_file);
F->CrashResistantMergeInternalStep(Flags.merge_control_file);
exit(0);
}
if (Flags.analyze_dict) {
size_t MaxLen = INT_MAX; // Large max length.
UnitVector InitialCorpus;
for (auto &Inp : *Inputs) {
Printf("Loading corpus dir: %s\n", Inp.c_str());
ReadDirToVectorOfUnits(Inp.c_str(), &InitialCorpus, nullptr,
MaxLen, /*ExitOnError=*/false);
}
if (Dictionary.empty() || Inputs->empty()) {
Printf("ERROR: can't analyze dict without dict and corpus provided\n");
return 1;
}
if (AnalyzeDictionary(F, Dictionary, InitialCorpus)) {
Printf("Dictionary analysis failed\n");
exit(1);
}
Printf("Dictionary analysis succeeded\n");
exit(0);
}
auto CorporaFiles = ReadCorpora(*Inputs, ParseSeedInuts(Flags.seed_inputs));
F->Loop(CorporaFiles);
if (Flags.verbosity)
Printf("Done %zd runs in %zd second(s)\n", F->getTotalNumberOfRuns(),
F->secondsSinceProcessStartUp());
F->PrintFinalStats();
exit(0); // Don't let F destroy itself.
}
extern "C" ATTRIBUTE_INTERFACE int
LLVMFuzzerRunDriver(int *argc, char ***argv,
int (*UserCb)(const uint8_t *Data, size_t Size)) {
return FuzzerDriver(argc, argv, UserCb);
}
// Storage for global ExternalFunctions object.
ExternalFunctions *EF = nullptr;
} // namespace fuzzer