Merge "tombstoned: don't create tombstones for failed dumps." (294d41cb) · Commits · e / os / android_system_core

debuggerd/tombstoned/tombstoned.cpp

+47 −28

Original line number	Diff line number	Diff line
		@@ -61,10 +61,10 @@ enum CrashStatus {
		struct Crash {
		~Crash() { event_free(crash_event); }

		unique_fd crash_fd;
		unique_fd crash_tombstone_fd;
		unique_fd crash_socket_fd;
		pid_t crash_pid;
		event* crash_event = nullptr;
		std::string crash_path;

		DebuggerdDumpType crash_type;
		};
		@@ -109,24 +109,27 @@ class CrashQueue {
		return &queue;
		}

		std::pair<unique_fd, std::string> get_output() {
		unique_fd result;
		std::string file_name = StringPrintf("%s%02d", file_name_prefix_.c_str(), next_artifact_);

		// Unlink and create the file, instead of using O_TRUNC, to avoid two processes
		// interleaving their output in case we ever get into that situation.
		if (unlinkat(dir_fd_, file_name.c_str(), 0) != 0 && errno != ENOENT) {
		PLOG(FATAL) << "failed to unlink tombstone at " << dir_path_ << "/" << file_name;
		}

		result.reset(openat(dir_fd_, file_name.c_str(),
		O_CREAT \| O_EXCL \| O_WRONLY \| O_APPEND \| O_CLOEXEC, 0640));
		unique_fd get_output() {
		unique_fd result(openat(dir_fd_, ".", O_WRONLY \| O_APPEND \| O_TMPFILE \| O_CLOEXEC, 0640));
		if (result == -1) {
		PLOG(FATAL) << "failed to create tombstone at " << dir_path_ << "/" << file_name;
		// We might not have O_TMPFILE. Try creating and unlinking instead.
		result.reset(
		openat(dir_fd_, ".temporary", O_WRONLY \| O_APPEND \| O_CREAT \| O_TRUNC \| O_CLOEXEC, 0640));
		if (result == -1) {
		PLOG(FATAL) << "failed to create temporary tombstone in " << dir_path_;
		}
		if (unlinkat(dir_fd_, ".temporary", 0) != 0) {
		PLOG(FATAL) << "failed to unlink temporary tombstone";
		}
		}
		return result;
		}

		std::string get_next_artifact_path() {
		std::string file_name =
		StringPrintf("%s/%s%02d", dir_path_.c_str(), file_name_prefix_.c_str(), next_artifact_);
		next_artifact_ = (next_artifact_ + 1) % max_artifacts_;
		return {std::move(result), dir_path_ + "/" + file_name};
		return file_name;
		}

		bool maybe_enqueue_crash(Crash* crash) {
		@@ -203,14 +206,17 @@ static void crash_completed_cb(evutil_socket_t sockfd, short ev, void* arg);

		static void perform_request(Crash* crash) {
		unique_fd output_fd;
		if (!intercept_manager->GetIntercept(crash->crash_pid, crash->crash_type, &output_fd)) {
		std::tie(output_fd, crash->crash_path) = CrashQueue::for_crash(crash)->get_output();
		bool intercepted =
		intercept_manager->GetIntercept(crash->crash_pid, crash->crash_type, &output_fd);
		if (!intercepted) {
		output_fd = CrashQueue::for_crash(crash)->get_output();
		crash->crash_tombstone_fd.reset(dup(output_fd.get()));
		}

		TombstonedCrashPacket response = {
		.packet_type = CrashPacketType::kPerformDump
		};
		ssize_t rc = send_fd(crash->crash_fd, &response, sizeof(response), std::move(output_fd));
		ssize_t rc = send_fd(crash->crash_socket_fd, &response, sizeof(response), std::move(output_fd));
		if (rc == -1) {
		PLOG(WARNING) << "failed to send response to CrashRequest";
		goto fail;
		@@ -222,7 +228,7 @@ static void perform_request(Crash* crash) {
		struct timeval timeout = { 10, 0 };

		event_base* base = event_get_base(crash->crash_event);
		event_assign(crash->crash_event, base, crash->crash_fd, EV_TIMEOUT \| EV_READ,
		event_assign(crash->crash_event, base, crash->crash_socket_fd, EV_TIMEOUT \| EV_READ,
		crash_completed_cb, crash);
		event_add(crash->crash_event, &timeout);
		}
		@@ -243,7 +249,7 @@ static void crash_accept_cb(evconnlistener* listener, evutil_socket_t sockfd, so
		// and only native crashes on the native socket.
		struct timeval timeout = { 1, 0 };
		event* crash_event = event_new(base, sockfd, EV_TIMEOUT \| EV_READ, crash_request_cb, crash);
		crash->crash_fd.reset(sockfd);
		crash->crash_socket_fd.reset(sockfd);
		crash->crash_event = crash_event;
		event_add(crash_event, &timeout);
		}
		@@ -342,14 +348,27 @@ static void crash_completed_cb(evutil_socket_t sockfd, short ev, void* arg) {
		goto fail;
		}

		if (!crash->crash_path.empty()) {
		if (crash->crash_tombstone_fd != -1) {
		std::string fd_path = StringPrintf("/proc/self/fd/%d", crash->crash_tombstone_fd.get());
		std::string tombstone_path = CrashQueue::for_crash(crash)->get_next_artifact_path();
		int rc = unlink(tombstone_path.c_str());
		if (rc != 0) {
		PLOG(ERROR) << "failed to unlink tombstone at " << tombstone_path;
		goto fail;
		}

		rc = linkat(AT_FDCWD, fd_path.c_str(), AT_FDCWD, tombstone_path.c_str(), AT_SYMLINK_FOLLOW);
		if (rc != 0) {
		PLOG(ERROR) << "failed to link tombstone";
		} else {
		if (crash->crash_type == kDebuggerdJavaBacktrace) {
		LOG(ERROR) << "Traces for pid " << crash->crash_pid << " written to: " << crash->crash_path;
		LOG(ERROR) << "Traces for pid " << crash->crash_pid << " written to: " << tombstone_path;
		} else {
		// NOTE: Several tools parse this log message to figure out where the
		// tombstone associated with a given native crash was written. Any changes
		// to this message must be carefully considered.
		LOG(ERROR) << "Tombstone written to: " << crash->crash_path;
		LOG(ERROR) << "Tombstone written to: " << tombstone_path;
		}
		}
		}