Merge "debuggerd_client: also log errors to the dump file." (8d7c887b) · Commits · e / os / android_system_core

debuggerd/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -8,6 +8,7 @@ cc_defaults {
		"-Wall",
		"-Wextra",
		"-Werror",
		"-Wno-gcc-compat",
		"-Wno-unused-argument",
		"-Wno-unused-function",
		"-Wno-nullability-completeness",

debuggerd/client/debuggerd_client.cpp

+93 −94

Original line number	Diff line number	Diff line
		@@ -47,19 +47,30 @@ using namespace std::chrono_literals;

		using android::base::ReadFileToString;
		using android::base::SendFileDescriptors;
		using android::base::StringAppendV;
		using android::base::unique_fd;
		using android::base::WriteStringToFd;

		static bool send_signal(pid_t pid, const DebuggerdDumpType dump_type) {
		const int signal = (dump_type == kDebuggerdJavaBacktrace) ? SIGQUIT : BIONIC_SIGNAL_DEBUGGER;
		sigval val;
		val.sival_int = (dump_type == kDebuggerdNativeBacktrace) ? 1 : 0;
		#define TAG "libdebuggerd_client: "

		if (sigqueue(pid, signal, val) != 0) {
		PLOG(ERROR) << "libdebuggerd_client: failed to send signal to pid " << pid;
		return false;
		// Log an error both to the log (via LOG(ERROR)) and to the given fd.
		static void log_error(int fd, int errno_value, const char* format, ...) __printflike(3, 4) {
		std::string message(TAG);

		va_list ap;
		va_start(ap, format);
		StringAppendV(&message, format, ap);
		va_end(ap);

		if (errno_value != 0) {
		message = message + ": " + strerror(errno_value);
		}
		return true;

		if (fd != -1) {
		dprintf(fd, "%s\n", message.c_str());
		}

		LOG(ERROR) << message;
		}

		template <typename Duration>
		@@ -74,13 +85,11 @@ static void populate_timeval(struct timeval* tv, const Duration& duration) {
		* Returns the wchan data for each thread in the process,
		* or empty string if unable to obtain any data.
		*/
		static std::string get_wchan_data(pid_t pid) {
		std::stringstream buffer;
		static std::string get_wchan_data(int fd, pid_t pid) {
		std::vector<pid_t> tids;

		if (!android::procinfo::GetProcessTids(pid, &tids)) {
		LOG(WARNING) << "libdebuggerd_client: Failed to get process tids";
		return buffer.str();
		log_error(fd, 0, "failed to get process tids");
		return "";
		}

		std::stringstream data;
		@@ -88,12 +97,13 @@ static std::string get_wchan_data(pid_t pid) {
		std::string path = "/proc/" + std::to_string(pid) + "/task/" + std::to_string(tid) + "/wchan";
		std::string wchan_str;
		if (!ReadFileToString(path, &wchan_str, true)) {
		PLOG(WARNING) << "libdebuggerd_client: Failed to read \"" << path << "\"";
		log_error(fd, errno, "failed to read \"%s\"", path.c_str());
		continue;
		}
		data << "sysTid=" << std::left << std::setw(10) << tid << wchan_str << "\n";
		}

		std::stringstream buffer;
		if (std::string str = data.str(); !str.empty()) {
		buffer << "\n----- Waiting Channels: pid " << pid << " at " << get_timestamp() << " -----\n"
		<< "Cmd line: " << android::base::Join(get_command_line(pid), " ") << "\n";
		@@ -101,16 +111,9 @@ static std::string get_wchan_data(pid_t pid) {
		buffer << "----- end " << std::to_string(pid) << " -----\n";
		buffer << "\n";
		}

		return buffer.str();
		}

		static void dump_wchan_data(const std::string& data, int fd, pid_t pid) {
		if (!WriteStringToFd(data, fd)) {
		LOG(WARNING) << "libdebuggerd_client: Failed to dump wchan data for pid: " << pid;
		}
		}

		bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int timeout_ms,
		unique_fd output_fd) {
		pid_t pid = tid;
		@@ -119,51 +122,51 @@ bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int
		android::procinfo::ProcessInfo procinfo;
		std::string error;
		if (!android::procinfo::GetProcessInfo(tid, &procinfo, &error)) {
		LOG(ERROR) << "libdebugged_client: failed to get process info: " << error;
		log_error(output_fd, 0, "failed to get process info: %s", error.c_str());
		return false;
		}
		pid = procinfo.pid;
		}

		LOG(INFO) << "libdebuggerd_client: started dumping process " << pid;
		unique_fd sockfd;
		LOG(INFO) << TAG "started dumping process " << pid;

		// Rather than try to deal with poll() all the way through the flow, we update
		// the socket timeout between each step (and only use poll() during the final
		// copy loop).
		const auto end = std::chrono::steady_clock::now() + std::chrono::milliseconds(timeout_ms);
		auto time_left = [&end]() { return end - std::chrono::steady_clock::now(); };
		auto set_timeout = [timeout_ms, &time_left](int sockfd) {
		if (timeout_ms <= 0) {
		return sockfd;
		}
		auto update_timeout = [timeout_ms, &output_fd](int sockfd, auto end) {
		if (timeout_ms <= 0) return true;

		auto remaining = time_left();
		auto remaining = end - std::chrono::steady_clock::now();
		if (remaining < decltype(remaining)::zero()) {
		LOG(ERROR) << "libdebuggerd_client: timeout expired";
		return -1;
		log_error(output_fd, 0, "timeout expired");
		return false;
		}

		struct timeval timeout;
		populate_timeval(&timeout, remaining);

		if (setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout)) != 0) {
		PLOG(ERROR) << "libdebuggerd_client: failed to set receive timeout";
		return -1;
		log_error(output_fd, errno, "failed to set receive timeout");
		return false;
		}
		if (setsockopt(sockfd, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout)) != 0) {
		PLOG(ERROR) << "libdebuggerd_client: failed to set send timeout";
		return -1;
		log_error(output_fd, errno, "failed to set send timeout");
		return false;
		}

		return sockfd;
		return true;
		};

		sockfd.reset(socket(AF_LOCAL, SOCK_SEQPACKET, 0));
		unique_fd sockfd(socket(AF_LOCAL, SOCK_SEQPACKET, 0));
		if (sockfd == -1) {
		PLOG(ERROR) << "libdebugger_client: failed to create socket";
		log_error(output_fd, errno, "failed to create socket");
		return false;
		}

		if (socket_local_client_connect(set_timeout(sockfd.get()), kTombstonedInterceptSocketName,
		if (!update_timeout(sockfd, end)) return false;

		if (socket_local_client_connect(sockfd.get(), kTombstonedInterceptSocketName,
		ANDROID_SOCKET_NAMESPACE_RESERVED, SOCK_SEQPACKET) == -1) {
		PLOG(ERROR) << "libdebuggerd_client: failed to connect to tombstoned";
		log_error(output_fd, errno, "failed to connect to tombstoned");
		return false;
		}

		@@ -171,15 +174,11 @@ bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int
		.dump_type = dump_type,
		.pid = pid,
		};
		if (!set_timeout(sockfd)) {
		PLOG(ERROR) << "libdebugger_client: failed to set timeout";
		return false;
		}

		// Create an intermediate pipe to pass to the other end.
		unique_fd pipe_read, pipe_write;
		if (!Pipe(&pipe_read, &pipe_write)) {
		PLOG(ERROR) << "libdebuggerd_client: failed to create pipe";
		log_error(output_fd, errno, "failed to create pipe");
		return false;
		}

		@@ -194,71 +193,69 @@ bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int
		}

		if (fcntl(pipe_read.get(), F_SETPIPE_SZ, pipe_buffer_size) != pipe_buffer_size) {
		PLOG(ERROR) << "failed to set pipe buffer size";
		log_error(output_fd, errno, "failed to set pipe buffer size");
		}

		ssize_t rc = SendFileDescriptors(set_timeout(sockfd), &req, sizeof(req), pipe_write.get());
		if (!update_timeout(sockfd, end)) return false;
		ssize_t rc = SendFileDescriptors(sockfd, &req, sizeof(req), pipe_write.get());
		pipe_write.reset();
		if (rc != sizeof(req)) {
		PLOG(ERROR) << "libdebuggerd_client: failed to send output fd to tombstoned";
		log_error(output_fd, errno, "failed to send output fd to tombstoned");
		return false;
		}

		// Check to make sure we've successfully registered.
		InterceptResponse response;
		rc = TEMP_FAILURE_RETRY(recv(set_timeout(sockfd.get()), &response, sizeof(response), MSG_TRUNC));
		auto get_response = [&output_fd](const char* kind, int sockfd, InterceptResponse* response) {
		ssize_t rc = TEMP_FAILURE_RETRY(recv(sockfd, response, sizeof(*response), MSG_TRUNC));
		if (rc == 0) {
		LOG(ERROR) << "libdebuggerd_client: failed to read initial response from tombstoned: "
		<< "timeout reached?";
		log_error(output_fd, 0, "failed to read %s response from tombstoned: timeout reached?", kind);
		return false;
		} else if (rc == -1) {
		PLOG(ERROR) << "libdebuggerd_client: failed to read initial response from tombstoned";
		log_error(output_fd, errno, "failed to read %s response from tombstoned", kind);
		return false;
		} else if (rc != sizeof(response)) {
		LOG(ERROR) << "libdebuggerd_client: received packet of unexpected length from tombstoned while "
		"reading initial response: expected "
		<< sizeof(response) << ", received " << rc;
		} else if (rc != sizeof(*response)) {
		log_error(output_fd, 0,
		"received packet of unexpected length from tombstoned while reading %s response: "
		"expected %zd, received %zd",
		kind, sizeof(response), rc);
		return false;
		}
		return true;
		};

		// Check to make sure we've successfully registered.
		InterceptResponse response;
		if (!update_timeout(sockfd, end)) return false;
		if (!get_response("initial", sockfd, &response)) return false;
		if (response.status != InterceptStatus::kRegistered) {
		LOG(ERROR) << "libdebuggerd_client: unexpected registration response: "
		<< static_cast<int>(response.status);
		return false;
		}

		if (!send_signal(tid, dump_type)) {
		log_error(output_fd, 0, "unexpected registration response: %d",
		static_cast<int>(response.status));
		return false;
		}

		rc = TEMP_FAILURE_RETRY(recv(set_timeout(sockfd.get()), &response, sizeof(response), MSG_TRUNC));
		if (rc == 0) {
		LOG(ERROR) << "libdebuggerd_client: failed to read status response from tombstoned: "
		"timeout reached?";
		return false;
		} else if (rc == -1) {
		PLOG(ERROR) << "libdebuggerd_client: failed to read status response from tombstoned";
		return false;
		} else if (rc != sizeof(response)) {
		LOG(ERROR) << "libdebuggerd_client: received packet of unexpected length from tombstoned while "
		"reading confirmation response: expected "
		<< sizeof(response) << ", received " << rc;
		// Send the signal.
		const int signal = (dump_type == kDebuggerdJavaBacktrace) ? SIGQUIT : BIONIC_SIGNAL_DEBUGGER;
		sigval val = {.sival_int = (dump_type == kDebuggerdNativeBacktrace) ? 1 : 0};
		if (sigqueue(pid, signal, val) != 0) {
		log_error(output_fd, errno, "failed to send signal to pid %d", pid);
		return false;
		}

		if (!update_timeout(sockfd, end)) return false;
		if (!get_response("status", sockfd, &response)) return false;
		if (response.status != InterceptStatus::kStarted) {
		response.error_message[sizeof(response.error_message) - 1] = '\0';
		LOG(ERROR) << "libdebuggerd_client: tombstoned reported failure: " << response.error_message;
		log_error(output_fd, 0, "tombstoned reported failure: %s", response.error_message);
		return false;
		}

		// Forward output from the pipe to the output fd.
		while (true) {
		auto remaining_ms = std::chrono::duration_cast<std::chrono::milliseconds>(time_left()).count();
		auto remaining = end - std::chrono::steady_clock::now();
		auto remaining_ms = std::chrono::duration_cast<std::chrono::milliseconds>(remaining).count();
		if (timeout_ms <= 0) {
		remaining_ms = -1;
		} else if (remaining_ms < 0) {
		LOG(ERROR) << "libdebuggerd_client: timeout expired";
		log_error(output_fd, 0, "timeout expired");
		return false;
		}

		@@ -271,11 +268,11 @@ bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int
		if (errno == EINTR) {
		continue;
		} else {
		PLOG(ERROR) << "libdebuggerd_client: error while polling";
		log_error(output_fd, errno, "error while polling");
		return false;
		}
		} else if (rc == 0) {
		LOG(ERROR) << "libdebuggerd_client: timeout expired";
		log_error(output_fd, 0, "timeout expired");
		return false;
		}

		@@ -285,17 +282,17 @@ bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int
		// Done.
		break;
		} else if (rc == -1) {
		PLOG(ERROR) << "libdebuggerd_client: error while reading";
		log_error(output_fd, errno, "error while reading");
		return false;
		}

		if (!android::base::WriteFully(output_fd.get(), buf, rc)) {
		PLOG(ERROR) << "libdebuggerd_client: error while writing";
		log_error(output_fd, errno, "error while writing");
		return false;
		}
		}

		LOG(INFO) << "libdebuggerd_client: done dumping process " << pid;
		LOG(INFO) << TAG "done dumping process " << pid;

		return true;
		}
		@@ -313,14 +310,16 @@ int dump_backtrace_to_file_timeout(pid_t tid, DebuggerdDumpType dump_type, int t

		// debuggerd_trigger_dump results in every thread in the process being interrupted
		// by a signal, so we need to fetch the wchan data before calling that.
		std::string wchan_data = get_wchan_data(tid);
		std::string wchan_data = get_wchan_data(fd, tid);

		int timeout_ms = timeout_secs > 0 ? timeout_secs * 1000 : 0;
		int ret = debuggerd_trigger_dump(tid, dump_type, timeout_ms, std::move(copy)) ? 0 : -1;

		// Dump wchan data, since only privileged processes (CAP_SYS_ADMIN) can read
		// kernel stack traces (/proc/*/stack).
		dump_wchan_data(wchan_data, fd, tid);
		if (!WriteStringToFd(wchan_data, fd)) {
		LOG(WARNING) << TAG "Failed to dump wchan data for pid: " << tid;
		}

		return ret;
		}