Merge "debuggerd: don't leave a zombie child if crash_dump is killed." am: 44b7cb92d6 (5a12472b) · Commits · e / os / android_system_core

debuggerd/handler/debuggerd_handler.cpp

+29 −22

Original line number	Diff line number	Diff line
		@@ -417,23 +417,28 @@ static int debuggerd_dispatch_pseudothread(void* arg) {
		// us to fork off a process to read memory from.
		char buf[4];
		rc = TEMP_FAILURE_RETRY(read(input_read.get(), &buf, sizeof(buf)));

		bool success = false;
		if (rc == 1 && buf[0] == '\1') {
		// crash_dump successfully started, and is ptracing us.
		// Fork off a copy of our address space for it to use.
		create_vm_process();
		success = true;
		} else {
		// Something went wrong, log it.
		if (rc == -1) {
		async_safe_format_log(ANDROID_LOG_FATAL, "libc", "read of IPC pipe failed: %s", strerror(errno));
		return 1;
		async_safe_format_log(ANDROID_LOG_FATAL, "libc", "read of IPC pipe failed: %s",
		strerror(errno));
		} else if (rc == 0) {
		async_safe_format_log(ANDROID_LOG_FATAL, "libc", "crash_dump helper failed to exec");
		return 1;
		async_safe_format_log(ANDROID_LOG_FATAL, "libc",
		"crash_dump helper failed to exec, or was killed");
		} else if (rc != 1) {
		async_safe_format_log(ANDROID_LOG_FATAL, "libc",
		"read of IPC pipe returned unexpected value: %zd", rc);
		return 1;
		} else if (buf[0] != '\1') {
		async_safe_format_log(ANDROID_LOG_FATAL, "libc", "crash_dump helper reported failure");
		return 1;
		}

		// crash_dump is ptracing us, fork off a copy of our address space for it to use.
		create_vm_process();
		}

		// Don't leave a zombie child.
		int status;
		@@ -444,14 +449,16 @@ static int debuggerd_dispatch_pseudothread(void* arg) {
		async_safe_format_log(ANDROID_LOG_FATAL, "libc", "crash_dump helper crashed or stopped");
		}

		if (success) {
		if (thread_info->siginfo->si_signo != BIONIC_SIGNAL_DEBUGGER) {
		// For crashes, we don't need to minimize pause latency.
		// Wait for the dump to complete before having the process exit, to avoid being murdered by
		// ActivityManager or init.
		TEMP_FAILURE_RETRY(read(input_read, &buf, sizeof(buf)));
		}
		}

		return 0;
		return success ? 0 : 1;
		}

		static void resend_signal(siginfo_t* info) {