From f9f672781cda1888b34edb1756753a3801063026 Mon Sep 17 00:00:00 2001 From: Xinhao Yuan Date: Thu, 9 Jul 2026 08:29:10 -0700 Subject: [PATCH] No public description PiperOrigin-RevId: 945131828 --- centipede/BUILD | 2 - centipede/centipede_test.cc | 35 +-- centipede/engine_worker.cc | 268 ++++++++++++++++-- .../testing/test_binary_for_engine_testing.cc | 8 +- 4 files changed, 260 insertions(+), 53 deletions(-) diff --git a/centipede/BUILD b/centipede/BUILD index 607811f8d..683b2afde 100644 --- a/centipede/BUILD +++ b/centipede/BUILD @@ -991,8 +991,6 @@ cc_library( ":runner_result", ":shared_memory_blob_sequence", "@abseil-cpp//absl/base:nullability", - "@abseil-cpp//absl/random", - "@abseil-cpp//absl/random:bit_gen_ref", "@com_google_fuzztest//common:defs", ], ) diff --git a/centipede/centipede_test.cc b/centipede/centipede_test.cc index 17383e8f3..c48578121 100644 --- a/centipede/centipede_test.cc +++ b/centipede/centipede_test.cc @@ -86,7 +86,7 @@ class CentipedeMock : public CentipedeCallbacks { // i-th element is the number of bytes with the value 'i' in the input. // `counters` is converted to FeatureVec and added to // `batch_result.results()`. - for (auto &input : inputs) { + for (auto& input : inputs) { ByteArray counters(256); for (uint8_t byte : input) { counters[byte]++; @@ -496,7 +496,7 @@ TEST_F(CentipedeWithTemporaryLocalDir, MutateViaExternalBinary) { // Must contain normal mutants, but not the ones from crossover. const auto mutant_data = GetDataFromMutants(result.mutants()); EXPECT_THAT(mutant_data, IsSupersetOf(some_of_expected_mutants)); - for (const auto &crossover_mutant : expected_crossover_mutants) { + for (const auto& crossover_mutant : expected_crossover_mutants) { EXPECT_THAT(mutant_data, Not(Contains(crossover_mutant))); } } @@ -525,7 +525,7 @@ class MergeMock : public CentipedeCallbacks { std::vector Mutate(absl::Span inputs, size_t num_mutants) override { std::vector mutants(num_mutants); - for (auto &mutant : mutants) { + for (auto& mutant : mutants) { mutant.data.resize(1); mutant.data[0] = ++number_of_mutations_; mutant.origin = Mutant::kOriginNone; @@ -611,7 +611,7 @@ class FunctionFilterMock : public CentipedeCallbacks { // Sets the inputs to one of 3 pre-defined values. std::vector Mutate(absl::Span inputs, size_t num_mutants) override { - for (auto &input : inputs) { + for (auto& input : inputs) { if (!seed_inputs_.contains(input.data)) { observed_inputs_.insert(input.data); } @@ -628,8 +628,8 @@ class FunctionFilterMock : public CentipedeCallbacks { // Returns one of 3 pre-defined values, that trigger different code paths in // the test target. static ByteArray GetMutant(size_t idx) { - const char *mutants[3] = {"func1", "func2-A", "foo"}; - const char *mutant = mutants[idx % 3]; + const char* mutants[3] = {"func1", "func2-A", "foo"}; + const char* mutant = mutants[idx % 3]; return {mutant, mutant + strlen(mutant)}; } @@ -646,7 +646,7 @@ class FunctionFilterMock : public CentipedeCallbacks { // Runs a short fuzzing session with the provided `function_filter`. // Returns a sorted array of observed inputs. static std::vector RunWithFunctionFilter( - std::string_view function_filter, const TempDir &tmp_dir) { + std::string_view function_filter, const TempDir& tmp_dir) { Environment env; env.workdir = tmp_dir.path(); env.seed = 1; // make the runs predictable. @@ -717,9 +717,9 @@ class ExtraBinariesMock : public CentipedeCallbacks { bool Execute(std::string_view binary, absl::Span inputs, BatchResult& batch_result) override { bool res = true; - for (const auto &input : inputs) { + for (const auto& input : inputs) { if (input.size() != 1) continue; - for (const Crash &crash : crashes_) { + for (const Crash& crash : crashes_) { if (binary == crash.binary && input[0] == crash.input) { batch_result.exit_code() = EXIT_FAILURE; batch_result.failure_description() = crash.description; @@ -736,7 +736,7 @@ class ExtraBinariesMock : public CentipedeCallbacks { std::vector Mutate(absl::Span inputs, size_t num_mutants) override { std::vector mutants(num_mutants); - for (auto &mutant : mutants) { + for (auto& mutant : mutants) { mutant.data.resize(1); mutant.data[0] = ++number_of_mutations_; mutant.origin = Mutant::kOriginNone; @@ -754,20 +754,20 @@ struct FileAndContents { std::string file; std::string contents; - bool operator==(const FileAndContents &other) const { + bool operator==(const FileAndContents& other) const { return file == other.file && contents == other.contents; } template - friend void AbslStringify(Sink &sink, const FileAndContents &f) { + friend void AbslStringify(Sink& sink, const FileAndContents& f) { absl::Format(&sink, "FileAndContents{%s, \"%s\"}", f.file, f.contents); } }; MATCHER_P(HasFilesWithContents, expected_files_and_contents, "") { - const std::string &dir_path = arg; + const std::string& dir_path = arg; std::vector files_and_contents; - for (const auto &dir_ent : std::filesystem::directory_iterator(dir_path)) { + for (const auto& dir_ent : std::filesystem::directory_iterator(dir_path)) { auto file_and_contents = FileAndContents{dir_ent.path().filename()}; ReadFromLocalFile(dir_ent.path().c_str(), file_and_contents.contents); files_and_contents.push_back(std::move(file_and_contents)); @@ -843,7 +843,7 @@ class UndetectedCrashingInputMock : public CentipedeCallbacks { if (!first_pass_) { num_inputs_triaged_ += inputs.size(); } - for (const auto &input : inputs) { + for (const auto& input : inputs) { FUZZTEST_CHECK_EQ(input.size(), 1); // By construction in `Mutate()`. // The contents of each mutant is its sequential number. if (input[0] == crashing_input_idx_) { @@ -933,7 +933,7 @@ TEST(Centipede, UndetectedCrashingInput) { absl::StrCat("crashing_batch-", crashing_input_hash); EXPECT_TRUE(std::filesystem::exists(crashes_dir_path)) << crashes_dir_path; std::vector found_crash_file_names; - for (auto const &dir_ent : + for (auto const& dir_ent : std::filesystem::directory_iterator(crashes_dir_path)) { found_crash_file_names.push_back(dir_ent.path().filename()); } @@ -1400,8 +1400,9 @@ TEST_F(CentipedeWithTemporaryLocalDir, EngineWorksInWorkerMode) { env.test_name = "some_test"; env.populate_binary_info = false; env.fork_server = false; - env.persistent_mode = false; + env.persistent_mode = true; env.exit_on_crash = true; + env.stop_at = absl::Now() + absl::Seconds(10); fuzztest::internal::DefaultCallbacksFactory< fuzztest::internal::CentipedeDefaultCallbacks> callbacks; diff --git a/centipede/engine_worker.cc b/centipede/engine_worker.cc index 01030d1eb..9d48b8303 100644 --- a/centipede/engine_worker.cc +++ b/centipede/engine_worker.cc @@ -12,6 +12,10 @@ // See the License for the specific language governing permissions and // limitations under the License. #include +#include +#include +#include +#include #include #include @@ -23,14 +27,13 @@ #include #include #include +#include #include #include #include #include #include "absl/base/nullability.h" -#include "absl/random/bit_gen_ref.h" -#include "absl/random/random.h" #include "./centipede/engine_abi.h" #include "./centipede/engine_worker_abi.h" #include "./centipede/execution_metadata.h" @@ -105,7 +108,7 @@ struct WorkerFlags { }; // The first call of this function must be outside of signal handlers since it -// allocates memory (enforced by `GetWorkerFlagsEarly`). After that it would be +// allocates memory (enforced by `WorkerInitEarly`). After that it would be // signal-safe. // // The worker flags format is `:(NAME=VALUE|SWITCH:)+`. `GetWorkerFlags` @@ -137,10 +140,6 @@ const WorkerFlags& GetWorkerFlags() { return worker_flags; } -__attribute__((constructor(200))) void GetWorkerFlagsEarly() { - (void)GetWorkerFlags(); -} - // `header` should be in the form of `FLAG_NAME=`. // // Extracts "value" as a null-terminated string from "\0FLAG_NAME=value\0" in @@ -220,6 +219,7 @@ enum class WorkerAction { kTestGetSeeds, kTestMutate, kTestExecute, + kNoOp, }; constexpr std::string_view kWorkerBinaryIdOutputFlagHeader = @@ -237,6 +237,10 @@ constexpr std::string_view kWorkerInputsBlobSequencePathFlagHeader = "arg1="; // TODO: Use better flag names when standardizing the protocol. constexpr std::string_view kWorkerOutputsBlobSequencePathFlagHeader = "arg2="; // TODO: Use better flag names when standardizing the protocol. +constexpr std::string_view kWorkerPersistentModeSocketPathFlagHeader = + "persistent_mode_socket="; // TODO: Use better flag names when + // standardizing the protocol. +constexpr std::string_view kWorkerCrossOverLevel = "crossover_level="; struct WorkerState { std::atomic has_failure_output = false; @@ -244,6 +248,11 @@ struct WorkerState { std::atomic in_adapter_execute = false; std::atomic has_finding = false; std::atomic saved_binary_id = false; + + void ResetForPersistentMode() { + has_failure_output.store(false, std::memory_order_relaxed); + has_finding.store(false, std::memory_order_relaxed); + } }; WorkerState& GetWorkerState() { @@ -323,6 +332,64 @@ inline std::string_view ToStringView(const std::vector& bytes) { return {reinterpret_cast(bytes.data()), bytes.size()}; } +// Zero initialized. +static int persistent_mode_socket; + +__attribute__((constructor(200))) void WorkerInitEarly() { + const char* persistent_mode_socket_path = + GetWorkerFlag(kWorkerPersistentModeSocketPathFlagHeader); + if (persistent_mode_socket_path == nullptr) return; + persistent_mode_socket = socket(AF_UNIX, SOCK_STREAM, 0); + if (persistent_mode_socket < 0) { + WorkerLog( + "Failed to create persistent mode socket - not running persistent " + "mode.", + LogLnSync{}); + return; + } + + struct sockaddr_un addr{}; + addr.sun_family = AF_UNIX; + const size_t socket_path_len = strlen(persistent_mode_socket_path); + WorkerCheck( + socket_path_len < sizeof(addr.sun_path), + "persistent mode socket path string must be fit in sockaddr_un.sun_path"); + std::memcpy(addr.sun_path, persistent_mode_socket_path, socket_path_len); + + int connect_ret = 0; + do { + connect_ret = + connect(persistent_mode_socket, (struct sockaddr*)&addr, sizeof(addr)); + } while (connect_ret == -1 && errno == EINTR); + if (connect_ret == -1) { + WorkerLog("Failed to connect the persistent mode socket to ", + persistent_mode_socket_path, LogLnSync{}); + (void)close(persistent_mode_socket); + persistent_mode_socket = -1; + } + + int flags = fcntl(persistent_mode_socket, F_GETFD); + if (flags == -1) { + WorkerLog( + "fcntl(F_GETFD) failed on the persistent mode socket - exiting " + "persistent mode", + LogLnSync{}); + (void)close(persistent_mode_socket); + persistent_mode_socket = -1; + } + flags |= FD_CLOEXEC; + if (fcntl(persistent_mode_socket, F_SETFD, flags) == -1) { + WorkerLog( + "fcntl(F_SETFD) failed on the persistent mode socket - exiting " + "persistent mode", + LogLnSync{}); + (void)close(persistent_mode_socket); + persistent_mode_socket = -1; + } + WorkerLog("Persistent mode: connected to ", persistent_mode_socket_path, + LogLnSync{}); +} + BlobSequence* GetInputsBlobSequence() { static auto result = []() -> BlobSequence* { if (!HasWorkerSwitchFlag("shmem")) { @@ -349,8 +416,25 @@ BlobSequence* GetOutputsBlobSequence() { return result; } -WorkerAction GetWorkerAction() { - static WorkerAction worker_action = [] { +int GetCrossOverLevel() { + static int result = []() { + const char* cross_over_level_str = GetWorkerFlag(kWorkerCrossOverLevel); + if (cross_over_level_str != nullptr) { + const int parsed = + atoi(cross_over_level_str); // NOLINT: can't use strto64, etc. + if (0 <= parsed && parsed <= 100) return parsed; + } + // Default + return 50; + }(); + return result; +} + +std::optional GetWorkerAction() { + static auto worker_action = []() -> std::optional { + if (HasWorkerSwitchFlag("dump_configuration")) { + return WorkerAction::kNoOp; + } if (HasWorkerSwitchFlag("dump_binary_id")) { return WorkerAction::kGetBinaryId; } @@ -361,7 +445,9 @@ WorkerAction GetWorkerAction() { return WorkerAction::kTestGetSeeds; } auto* inputs_blobseq = GetInputsBlobSequence(); - WorkerCheck(inputs_blobseq != nullptr, "input blob sequence is not found"); + if (inputs_blobseq == nullptr) { + return std::nullopt; + } auto request_type_blob = inputs_blobseq->Read(); if (IsMutationRequest(request_type_blob)) { inputs_blobseq->Reset(); @@ -371,9 +457,7 @@ WorkerAction GetWorkerAction() { inputs_blobseq->Reset(); return WorkerAction::kTestExecute; } - WorkerCheck(false, "unknown worker action from the flags"); - // should not reach here. - std::abort(); + return std::nullopt; }(); return worker_action; } @@ -457,14 +541,6 @@ void WorkerDoGetSeeds(const FuzzTestAdapter& adapter) { } } -absl::BitGenRef GetBitGen() { - static thread_local std::unique_ptr bitgen; - if (bitgen == nullptr) { - bitgen = std::make_unique(); - } - return *bitgen; -} - void WorkerDoMutate(const FuzzTestAdapter& adapter) { auto* inputs_blobseq = GetInputsBlobSequence(); auto* outputs_blobseq = GetOutputsBlobSequence(); @@ -516,15 +592,25 @@ void WorkerDoMutate(const FuzzTestAdapter& adapter) { std::vector mutant_bytes; const auto mutant_bytes_sink = GetBytesSinkTo(mutant_bytes); + static unsigned int seed = 0; for (size_t i = 0; i < num_mutants; ++i) { - const auto origin = - absl::Uniform(GetBitGen(), 0, origin_inputs.size()); + // Assume RAND_MAX is large enough and not worry about fairness for now. + const auto origin = rand_r(&seed) % origin_inputs.size(); emitted_inputs.clear(); - adapter.Mutate(adapter.ctx, origin_inputs[origin], /*shrink=*/0, - &input_sink); + const bool do_cross_over = adapter.CrossOver != nullptr && + rand_r(&seed) % 100 < GetCrossOverLevel(); + if (do_cross_over) { + const auto other = rand_r(&seed) % origin_inputs.size(); + adapter.CrossOver(adapter.ctx, origin_inputs[origin], + origin_inputs[other], &input_sink); + } else { + adapter.Mutate(adapter.ctx, origin_inputs[origin], /*shrink=*/0, + &input_sink); + } WORKER_CHECK_FOR_ERROR(); WorkerCheck(emitted_inputs.size() == 1, - "Mutate must emit exactly one input"); + do_cross_over ? "CrossOver must emit exactly one input" + : "Mutate must emit exactly one input"); mutant_bytes.clear(); adapter.SerializeInputContent(adapter.ctx, emitted_inputs[0], &mutant_bytes_sink); @@ -596,6 +682,32 @@ void WorkerDoExecute(const FuzzTestAdapter& adapter) { return true; }(); + // Utils to get execution stats. + + size_t last_time_usec = 0; + auto UsecSinceLast = [&last_time_usec]() { + struct timeval tv = {}; + constexpr size_t kUsecInSec = 1000000; + gettimeofday(&tv, nullptr); + uint64_t t = tv.tv_sec * kUsecInSec + tv.tv_usec; + uint64_t ret_val = t - last_time_usec; + last_time_usec = t; + return ret_val; + }; + + auto GetPeakRSSMb = []() -> size_t { + struct rusage usage = {}; + if (getrusage(RUSAGE_SELF, &usage) != 0) return 0; +#ifdef __APPLE__ + // On MacOS, the unit seems to be byte according to experiment, while some + // documents mentioned KiB. This could depend on OS variants. + return usage.ru_maxrss >> 20; +#else // __APPLE__ + // On Linux, ru_maxrss is in KiB + return usage.ru_maxrss >> 10; +#endif // __APPLE__ + }; + // In-loop variables declared outside to save allocations. std::vector features; std::vector serialized_metadata; @@ -603,6 +715,16 @@ void WorkerDoExecute(const FuzzTestAdapter& adapter) { const auto input_sink = GetInputSinkTo(emitted_inputs); for (size_t i = 0; i < num_inputs; i++) { + // The stats gathered here are slightly different than + // the original definition: Here the exec_time_usec will cover the time used + // to process coverage feedback, which is usually fine for the purpose of + // corpus scheduling, but coverage processing can be non-deterministic due + // to optimization. E.g. Execute() may perform deep and slow cleanup on + // the beginning of consecutive Execute() calls to reduce noise. + // + // TODO(xinhaoyuan): Consider improving it. E.g. let user override stats. + ExecutionResult::Stats stats = {}; + UsecSinceLast(); auto blob = inputs_blobseq->Read(); if (!blob.IsValid()) return; // no more blobs to read. WorkerCheck(IsDataInput(blob), "Must read data input"); @@ -631,7 +753,9 @@ void WorkerDoExecute(const FuzzTestAdapter& adapter) { }}; GetWorkerState().in_adapter_execute = true; + stats.prep_time_usec = UsecSinceLast(); adapter.Execute(adapter.ctx, input, &feedback_sink); + stats.exec_time_usec = UsecSinceLast(); GetWorkerState().in_adapter_execute = false; WORKER_CHECK_FOR_ERROR(); @@ -681,6 +805,12 @@ void WorkerDoExecute(const FuzzTestAdapter& adapter) { WorkerLog("failed to write input metadata"); break; } + stats.post_time_usec = UsecSinceLast(); + stats.peak_rss_mb = GetPeakRSSMb(); + if (!BatchResult::WriteStats(stats, *outputs_blobseq)) { + WorkerLog("failed to write stats"); + break; + } if (!BatchResult::WriteInputEnd(*outputs_blobseq)) { WorkerLog("failed to write input end"); break; @@ -695,6 +825,72 @@ const char* FuzzTestWorkerGetTestName() { return test_name; } +void HandlePersistentMode(const FuzzTestAdapter& adapter) { + auto* inputs_blobseq = GetInputsBlobSequence(); + auto* outputs_blobseq = GetOutputsBlobSequence(); + bool first = true; + while (true) { + PersistentModeRequest req; + if (!ReadAll(persistent_mode_socket, reinterpret_cast(&req), 1)) { + WorkerLog("Failed to read request from persistent mode socket: ", + LogErrNo{}, LogLnSync{}); + return; + } + if (first) { + first = false; + WorkerLog("FuzzTest engine worker enter persistent mode", LogLnSync{}); + } else { + // Reset stdout/stderr. + for (int fd = 1; fd <= 2; fd++) { + lseek(fd, 0, SEEK_SET); + // NOTE: Allow ftruncate() to fail by ignoring its return; that's okay + // to happen when the stdout/stderr are not redirected to a file. + (void)ftruncate(fd, 0); + } + WorkerLog( + "FuzzTest engine worker (", + req == PersistentModeRequest::kExit ? "exiting persistent mode" + : "persistent mode batch", + "); flags: ", + GetWorkerFlags().present + ? std::string_view{GetWorkerFlags().str, GetWorkerFlags().len} + : "", + LogLnSync{}); + } + if (req == PersistentModeRequest::kExit) break; + WorkerCheck(req == PersistentModeRequest::kRunBatch, + "Unknown persistent mode request"); + + inputs_blobseq->Reset(); + outputs_blobseq->Reset(); + + GetWorkerState().ResetForPersistentMode(); + + // Read the first blob. It indicates what further actions to take. + auto request_type_blob = inputs_blobseq->Read(); + if (IsMutationRequest(request_type_blob)) { + inputs_blobseq->Reset(); + WorkerDoMutate(adapter); + } else if (IsExecutionRequest(request_type_blob)) { + inputs_blobseq->Reset(); + WorkerDoExecute(adapter); + } else { + WorkerCheck(false, "Unknown shmem request"); + } + + const int result = + GetWorkerState().has_finding.load(std::memory_order_relaxed) + ? EXIT_FAILURE + : EXIT_SUCCESS; + if (!WriteAll(persistent_mode_socket, + reinterpret_cast(&result), sizeof(result))) { + WorkerLog("Failed to write response to the persistent mode socket: ", + LogErrNo{}, LogLnSync{}); + return; + } + } +} + FuzzTestWorkerStatus WorkerRun(const FuzzTestAdapterManager& manager) { const auto& flags = GetWorkerFlags(); WorkerCheck(flags.present, "worker flags must present"); @@ -704,6 +900,12 @@ FuzzTestWorkerStatus WorkerRun(const FuzzTestAdapterManager& manager) { } const auto action = GetWorkerAction(); + WorkerCheck(action.has_value(), "No worker action to run"); + + if (action == WorkerAction::kNoOp) { + return kFuzzTestWorkerSuccess; + } + if (action == WorkerAction::kGetBinaryId) { WorkerDoGetBinaryId(manager); return kFuzzTestWorkerSuccess; @@ -748,8 +950,8 @@ FuzzTestWorkerStatus WorkerRun(const FuzzTestAdapterManager& manager) { WorkerCheck(manager.ConstructAdapter != nullptr, "ConstructAdapter is not defined"); FuzzTestAdapter adapter = {}; - manager.ConstructAdapter(manager.ctx, /*diagnostic_sink=*/&diagnostic_sink, - &adapter); + manager.ConstructAdapter(manager.ctx, + /*diagnostic_sink=*/&diagnostic_sink, &adapter); WORKER_CHECK_FOR_ERROR(); WorkerCheck(adapter.SetUpCoverageDomains != nullptr, "SetUpCoverageDomains must be defined"); @@ -764,7 +966,9 @@ FuzzTestWorkerStatus WorkerRun(const FuzzTestAdapterManager& manager) { WorkerCheck(adapter.FreeInput != nullptr, "FreeInput must be defined"); WorkerCheck(adapter.FreeCtx != nullptr, "FreeCtx must be defined"); - if (action == WorkerAction::kTestGetSeeds) { + if (persistent_mode_socket > 0) { + HandlePersistentMode(adapter); + } else if (action == WorkerAction::kTestGetSeeds) { WorkerDoGetSeeds(adapter); } else if (action == WorkerAction::kTestMutate) { WorkerDoMutate(adapter); @@ -794,7 +998,11 @@ using ::fuzztest::internal::WorkerRun; } // namespace -int FuzzTestWorkerIsRequired() { return GetWorkerFlags().present; } +int FuzzTestWorkerIsRequired() { + static int result = GetWorkerFlags().present && + fuzztest::internal::GetWorkerAction().has_value(); + return result; +} FuzzTestWorkerStatus FuzzTestWorkerMaybeRun( const FuzzTestAdapterManager* manager) { diff --git a/centipede/testing/test_binary_for_engine_testing.cc b/centipede/testing/test_binary_for_engine_testing.cc index 75c1a42a5..071f2232c 100644 --- a/centipede/testing/test_binary_for_engine_testing.cc +++ b/centipede/testing/test_binary_for_engine_testing.cc @@ -202,10 +202,10 @@ int main(int argc, char** argv) { return worker_status == kFuzzTestWorkerSuccess ? EXIT_SUCCESS : EXIT_FAILURE; } - return ControllerRun(&manager, {absl::StrCat("--binary=", argv[0]), - "--test_name=some_test", - "--populate_binary_info=0", "--fork_server=0", - "--persistent_mode=0", "--exit_on_crash"}) == + return ControllerRun(&manager, + {absl::StrCat("--binary=", argv[0]), + "--test_name=some_test", "--populate_binary_info=0", + "--fork_server=0", "--exit_on_crash"}) == kFuzzTestControllerSuccess ? EXIT_SUCCESS : EXIT_FAILURE;