Merge "Revert "init: Fix a race condition in KillProcessGroup()"" (8462ceef) · Commits · e / os / android_system_core

init/service.cpp

+3 −35

Original line number	Diff line number	Diff line
		@@ -507,7 +507,7 @@ void Service::ConfigureMemcg() {

		// Enters namespaces, sets environment variables, writes PID files and runs the service executable.
		void Service::RunService(const std::vector<Descriptor>& descriptors,
		InterprocessFifo cgroups_activated, InterprocessFifo setsid_finished) {
		InterprocessFifo cgroups_activated) {
		if (auto result = EnterNamespaces(namespaces_, name_, mount_namespace_); !result.ok()) {
		LOG(FATAL) << "Service '" << name_ << "' failed to set up namespaces: " << result.error();
		}
		@@ -557,12 +557,6 @@ void Service::RunService(const std::vector<Descriptor>& descriptors,
		// priority. Aborts on failure.
		SetProcessAttributesAndCaps();

		// If SetProcessAttributes() called setsid(), report this to the parent.
		if (!proc_attr_.console.empty()) {
		setsid_finished.Write(2);
		}
		setsid_finished.Close();

		if (!ExpandArgsAndExecv(args_, sigstop_)) {
		PLOG(ERROR) << "cannot execv('" << args_[0]
		<< "'). See the 'Debugging init' section of init's README.md for tips";
		@@ -604,7 +598,7 @@ Result<void> Service::Start() {
		return {};
		}

		InterprocessFifo cgroups_activated, setsid_finished;
		InterprocessFifo cgroups_activated;

		if (Result<void> result = cgroups_activated.Initialize(); !result.ok()) {
		return result;
		@@ -614,13 +608,6 @@ Result<void> Service::Start() {
		return result;
		}

		// Only check proc_attr_.console after the CheckConsole() call.
		if (!proc_attr_.console.empty()) {
		if (Result<void> result = setsid_finished.Initialize(); !result.ok()) {
		return result;
		}
		}

		struct stat sb;
		if (stat(args_[0].c_str(), &sb) == -1) {
		flags_ \|= SVC_DISABLED;
		@@ -674,12 +661,10 @@ Result<void> Service::Start() {
		if (pid == 0) {
		umask(077);
		cgroups_activated.CloseWriteFd();
		setsid_finished.CloseReadFd();
		RunService(descriptors, std::move(cgroups_activated), std::move(setsid_finished));
		RunService(descriptors, std::move(cgroups_activated));
		_exit(127);
		} else {
		cgroups_activated.CloseReadFd();
		setsid_finished.CloseWriteFd();
		}

		if (pid < 0) {
		@@ -736,23 +721,6 @@ Result<void> Service::Start() {
		return Error() << "Sending cgroups activated notification failed: " << result.error();
		}

		// Call setpgid() from the parent process to make sure that this call has
		// finished before the parent process calls kill(-pgid, ...).
		if (proc_attr_.console.empty()) {
		if (setpgid(pid, pid) == -1) {
		return ErrnoError() << "setpgid failed";
		}
		} else {
		// The Read() call below will return an error if the child is killed.
		if (Result<uint8_t> result = setsid_finished.Read(); !result.ok() \|\| *result != 2) {
		if (!result.ok()) {
		return Error() << "Waiting for setsid() failed: " << result.error();
		} else {
		return Error() << "Waiting for setsid() failed: " << *result << " <> 2";
		}
		}
		}

		NotifyStateChange("running");
		reboot_on_failure.Disable();
		return {};

init/service.h

+1 −2

Original line number	Diff line number	Diff line
		@@ -155,8 +155,7 @@ class Service {
		void ResetFlagsForStart();
		Result<void> CheckConsole();
		void ConfigureMemcg();
		void RunService(const std::vector<Descriptor>& descriptors, InterprocessFifo cgroups_activated,
		InterprocessFifo setsid_finished);
		void RunService(const std::vector<Descriptor>& descriptors, InterprocessFifo cgroups_activated);
		void SetMountNamespace();
		static unsigned long next_start_order_;
		static bool is_exec_service_running_;

init/service_utils.cpp

+1 −5

Original line number	Diff line number	Diff line
		@@ -244,11 +244,7 @@ Result<void> SetProcessAttributes(const ProcessAttributes& attr) {
		setsid();
		OpenConsole(attr.console);
		} else {
		// Without PID namespaces, this call duplicates the setpgid() call from
		// the parent process. With PID namespaces, this setpgid() call sets the
		// process group ID for a child of the init process in the PID
		// namespace.
		if (setpgid(0, 0) == -1) {
		if (setpgid(0, getpid()) == -1) {
		return ErrnoError() << "setpgid failed";
		}
		SetupStdio(attr.stdio_to_kmsg);