Merge changes Id5f03945,I69c74471 am: 23ae9df08e am: cc37c07a8b (70f1517e) · Commits · e / os / android_system_core

logd/LogTags.cpp

+2 −0

Original line number	Diff line number	Diff line
		@@ -276,7 +276,9 @@ void LogTags::ReadFileEventLogTags(const char* filename, bool warn) {
		cp++;
		}
		} else if (warn) {
		#ifdef __ANDROID__
		LOG(ERROR) << "Cannot read " << filename;
		#endif
		}
		}

logd/SerializedLogBuffer.cpp

+47 −17

Original line number	Diff line number	Diff line
		@@ -16,8 +16,9 @@

		#include "SerializedLogBuffer.h"

		#include <sys/prctl.h>

		#include <limits>
		#include <thread>

		#include <android-base/logging.h>
		#include <android-base/scopeguard.h>
		@@ -31,7 +32,11 @@ SerializedLogBuffer::SerializedLogBuffer(LogReaderList* reader_list, LogTags* ta
		Init();
		}

		SerializedLogBuffer::~SerializedLogBuffer() {}
		SerializedLogBuffer::~SerializedLogBuffer() {
		if (deleter_thread_.joinable()) {
		deleter_thread_.join();
		}
		}

		void SerializedLogBuffer::Init() {
		log_id_for_each(i) {
		@@ -119,15 +124,44 @@ void SerializedLogBuffer::MaybePrune(log_id_t log_id) {
		}
		}

		void SerializedLogBuffer::StartDeleterThread() {
		if (deleter_thread_running_) {
		return;
		}
		if (deleter_thread_.joinable()) {
		deleter_thread_.join();
		}
		auto new_thread = std::thread([this] { DeleterThread(); });
		deleter_thread_.swap(new_thread);
		deleter_thread_running_ = true;
		}

		// Decompresses the chunks, call LogStatistics::Subtract() on each entry, then delete the chunks and
		// the list. Note that the SerializedLogChunk objects have been removed from logs_ and their
		// references have been deleted from any SerializedFlushToState objects, so this can be safely done
		// without holding lock_. It is done in a separate thread to avoid delaying the writer thread. The
		// lambda for the thread takes ownership of the 'chunks' list and thus when the thread ends and the
		// lambda is deleted, the objects are deleted.
		void SerializedLogBuffer::DeleteLogChunks(std::list<SerializedLogChunk>&& chunks, log_id_t log_id) {
		auto delete_thread = std::thread{[chunks = std::move(chunks), log_id, this]() mutable {
		for (auto& chunk : chunks) {
		// without holding lock_. It is done in a separate thread to avoid delaying the writer thread.
		void SerializedLogBuffer::DeleterThread() {
		prctl(PR_SET_NAME, "logd.deleter");
		while (true) {
		std::list<SerializedLogChunk> local_chunks_to_delete;
		log_id_t log_id;
		{
		auto lock = std::lock_guard{lock_};
		log_id_for_each(i) {
		if (!chunks_to_delete_[i].empty()) {
		local_chunks_to_delete = std::move(chunks_to_delete_[i]);
		chunks_to_delete_[i].clear();
		log_id = i;
		break;
		}
		}
		if (local_chunks_to_delete.empty()) {
		deleter_thread_running_ = false;
		return;
		}
		}

		for (auto& chunk : local_chunks_to_delete) {
		chunk.IncReaderRefCount();
		int read_offset = 0;
		while (read_offset < chunk.write_offset()) {
		@@ -137,8 +171,7 @@ void SerializedLogBuffer::DeleteLogChunks(std::list<SerializedLogChunk>&& chunks
		}
		chunk.DecReaderRefCount(false);
		}
		}};
		delete_thread.detach();
		}
		}

		void SerializedLogBuffer::NotifyReadersOfPrune(
		@@ -164,13 +197,9 @@ bool SerializedLogBuffer::Prune(log_id_t log_id, size_t bytes_to_free, uid_t uid
		}
		}

		auto& log_buffer = logs_[log_id];

		std::list<SerializedLogChunk> chunks_to_prune;
		auto prune_chunks = android::base::make_scope_guard([&chunks_to_prune, log_id, this] {
		DeleteLogChunks(std::move(chunks_to_prune), log_id);
		});
		StartDeleterThread();

		auto& log_buffer = logs_[log_id];
		auto it = log_buffer.begin();
		while (it != log_buffer.end()) {
		if (oldest != nullptr && it->highest_sequence_number() >= oldest->start()) {
		@@ -193,7 +222,8 @@ bool SerializedLogBuffer::Prune(log_id_t log_id, size_t bytes_to_free, uid_t uid
		}
		} else {
		size_t buffer_size = it_to_prune->PruneSize();
		chunks_to_prune.splice(chunks_to_prune.end(), log_buffer, it_to_prune);
		chunks_to_delete_[log_id].splice(chunks_to_delete_[log_id].end(), log_buffer,
		it_to_prune);
		if (buffer_size >= bytes_to_free) {
		return true;
		}

logd/SerializedLogBuffer.h

+8 −1

Original line number	Diff line number	Diff line
		@@ -21,6 +21,7 @@
		#include <list>
		#include <mutex>
		#include <queue>
		#include <thread>
		#include <vector>

		#include <android-base/thread_annotations.h>
		@@ -60,7 +61,9 @@ class SerializedLogBuffer final : public LogBuffer {
		REQUIRES_SHARED(lock_);
		void NotifyReadersOfPrune(log_id_t log_id, const std::list<SerializedLogChunk>::iterator& chunk)
		REQUIRES(reader_list_->reader_threads_lock());
		void DeleteLogChunks(std::list<SerializedLogChunk>&& chunks, log_id_t log_id);

		void StartDeleterThread() REQUIRES(lock_);
		void DeleterThread();

		LogReaderList* reader_list_;
		LogTags* tags_;
		@@ -70,5 +73,9 @@ class SerializedLogBuffer final : public LogBuffer {
		std::list<SerializedLogChunk> logs_[LOG_ID_MAX] GUARDED_BY(lock_);
		RwLock lock_;

		std::list<SerializedLogChunk> chunks_to_delete_[LOG_ID_MAX] GUARDED_BY(lock_);
		std::thread deleter_thread_ GUARDED_BY(lock_);
		bool deleter_thread_running_ GUARDED_BY(lock_) = false;

		std::atomic<uint64_t> sequence_ = 1;
		};

logd/fuzz/Android.bp

+21 −7

Original line number	Diff line number	Diff line
		@@ -13,11 +13,9 @@
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/
		cc_fuzz {
		name: "log_buffer_log_fuzzer",
		srcs: [
		"log_buffer_log_fuzzer.cpp",
		],

		cc_defaults {
		name: "log_fuzzer_defaults",
		static_libs: [
		"libbase",
		"libcutils",
		@@ -25,9 +23,25 @@ cc_fuzz {
		"liblog",
		"liblogd",
		"libcutils",
		"libsysutils",
		"libz",
		"libzstd",
		],
		cflags: ["-Werror"],
		cflags: ["-Wextra"],
		host_supported: true,
		}

		cc_fuzz {
		name: "log_buffer_log_fuzzer",
		defaults: ["log_fuzzer_defaults"],
		srcs: [
		"log_buffer_log_fuzzer.cpp",
		],
		}

		cc_fuzz {
		name: "serialized_log_buffer_fuzzer",
		defaults: ["log_fuzzer_defaults"],
		srcs: [
		"serialized_log_buffer_fuzzer.cpp",
		],
		}

logd/fuzz/log_buffer_log_fuzzer.cpp

+52 −7

Original line number	Diff line number	Diff line
		@@ -15,10 +15,13 @@
		*/
		#include <string>

		#include <android-base/logging.h>

		#include "../ChattyLogBuffer.h"
		#include "../LogReaderList.h"
		#include "../LogReaderThread.h"
		#include "../LogStatistics.h"
		#include "../SerializedLogBuffer.h"

		// We don't want to waste a lot of entropy on messages
		#define MAX_MSG_LENGTH 5
		@@ -27,7 +30,20 @@
		#define MIN_TAG_ID 1000
		#define TAG_MOD 10

		namespace android {
		#ifndef __ANDROID__
		unsigned long __android_logger_get_buffer_size(log_id_t) {
		return 1024 * 1024;
		}

		bool __android_logger_valid_buffer_size(unsigned long) {
		return true;
		}
		#endif

		char* android::uidToName(uid_t) {
		return strdup("fake");
		}

		struct LogInput {
		public:
		log_id_t log_id;
		@@ -79,9 +95,13 @@ int write_log_messages(const uint8_t** pdata, size_t* data_left, LogBuffer* log_
		return 1;
		}

		char* uidToName(uid_t) {
		return strdup("fake");
		}
		class NoopWriter : public LogWriter {
		public:
		NoopWriter() : LogWriter(0, true) {}
		bool Write(const logger_entry&, const char*) override { return true; }

		std::string name() const override { return "noop_writer"; }
		};

		extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
		// We want a random tag length and a random remaining message length
		@@ -89,11 +109,18 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
		return 0;
		}

		android::base::SetMinimumLogSeverity(android::base::ERROR);

		LogReaderList reader_list;
		LogTags tags;
		PruneList prune_list;
		LogStatistics stats(true);
		LogBuffer* log_buffer = new ChattyLogBuffer(&reader_list, &tags, &prune_list, &stats);
		std::unique_ptr<LogBuffer> log_buffer;
		#ifdef FUZZ_SERIALIZED
		log_buffer.reset(new SerializedLogBuffer(&reader_list, &tags, &stats));
		#else
		log_buffer.reset(new ChattyLogBuffer(&reader_list, &tags, &prune_list, &stats));
		#endif
		size_t data_left = size;
		const uint8_t** pdata = &data;

		@@ -102,12 +129,30 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
		log_id_for_each(i) { log_buffer->SetSize(i, 10000); }

		while (data_left >= sizeof(LogInput) + 2 * sizeof(uint8_t)) {
		if (!write_log_messages(pdata, &data_left, log_buffer, &stats)) {
		if (!write_log_messages(pdata, &data_left, log_buffer.get(), &stats)) {
		return 0;
		}
		}

		// Read out all of the logs.
		{
		auto lock = std::unique_lock{reader_list.reader_threads_lock()};
		std::unique_ptr<LogWriter> test_writer(new NoopWriter());
		std::unique_ptr<LogReaderThread> log_reader(
		new LogReaderThread(log_buffer.get(), &reader_list, std::move(test_writer), true, 0,
		kLogMaskAll, 0, {}, 1, {}));
		reader_list.reader_threads().emplace_back(std::move(log_reader));
		}

		// Wait until the reader has finished.
		while (true) {
		usleep(50);
		auto lock = std::unique_lock{reader_list.reader_threads_lock()};
		if (reader_list.reader_threads().size() == 0) {
		break;
		}
		}

		log_id_for_each(i) { log_buffer->Clear(i, 0); }
		return 0;
		}
		} // namespace android