Merge "Reland^2: "init: run property service in a thread"" (4e46a33c) · Commits · e / os / android_system_core

init/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -129,6 +129,7 @@ cc_library_static {
		"persistent_properties.cpp",
		"persistent_properties.proto",
		"property_service.cpp",
		"property_service.proto",
		"property_type.cpp",
		"reboot.cpp",
		"reboot_utils.cpp",

init/builtins.cpp

+24 −1

Original line number	Diff line number	Diff line
		@@ -80,6 +80,7 @@
		using namespace std::literals::string_literals;

		using android::base::Basename;
		using android::base::StartsWith;
		using android::base::StringPrintf;
		using android::base::unique_fd;
		using android::fs_mgr::Fstab;
		@@ -701,6 +702,15 @@ static Result<void> do_swapon_all(const BuiltinArguments& args) {
		}

		static Result<void> do_setprop(const BuiltinArguments& args) {
		if (StartsWith(args[1], "ctl.")) {
		return Error()
		<< "Cannot set ctl. properties from init; call the Service functions directly";
		}
		if (args[1] == kRestoreconProperty) {
		return Error() << "Cannot set '" << kRestoreconProperty
		<< "' from init; use the restorecon builtin directly";
		}

		property_set(args[1], args[2]);
		return {};
		}
		@@ -1016,7 +1026,20 @@ static Result<void> do_loglevel(const BuiltinArguments& args) {
		}

		static Result<void> do_load_persist_props(const BuiltinArguments& args) {
		load_persist_props();
		// Devices with FDE have load_persist_props called twice; the first time when the temporary
		// /data partition is mounted and then again once /data is truly mounted. We do not want to
		// read persistent properties from the temporary /data partition or mark persistent properties
		// as having been loaded during the first call, so we return in that case.
		std::string crypto_state = android::base::GetProperty("ro.crypto.state", "");
		std::string crypto_type = android::base::GetProperty("ro.crypto.type", "");
		if (crypto_state == "encrypted" && crypto_type == "block") {
		static size_t num_calls = 0;
		if (++num_calls == 1) return {};
		}

		SendLoadPersistentPropertiesMessage();

		start_waiting_for_property("ro.persistent_properties.ready", "true");
		return {};
		}

init/init.cpp

+66 −1

Original line number	Diff line number	Diff line
		@@ -28,6 +28,9 @@
		#include <sys/types.h>
		#include <unistd.h>

		#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
		#include <sys/_system_properties.h>

		#include <functional>
		#include <map>
		#include <memory>
		@@ -60,6 +63,7 @@
		#include "mount_handler.h"
		#include "mount_namespace.h"
		#include "property_service.h"
		#include "proto_utils.h"
		#include "reboot.h"
		#include "reboot_utils.h"
		#include "security.h"
		@@ -68,6 +72,7 @@
		#include "service.h"
		#include "service_parser.h"
		#include "sigchld_handler.h"
		#include "system/core/init/property_service.pb.h"
		#include "util.h"

		using namespace std::chrono_literals;
		@@ -89,6 +94,7 @@ static int property_triggers_enabled = 0;
		static char qemu[32];

		static int signal_fd = -1;
		static int property_fd = -1;

		static std::unique_ptr<Timer> waiting_for_prop(nullptr);
		static std::string wait_prop_name;
		@@ -614,6 +620,60 @@ static void RecordStageBoottimes(const boot_clock::time_point& second_stage_star
		selinux_start_time_ns));
		}

		void SendLoadPersistentPropertiesMessage() {
		auto init_message = InitMessage{};
		init_message.set_load_persistent_properties(true);
		if (auto result = SendMessage(property_fd, init_message); !result) {
		LOG(ERROR) << "Failed to send load persistent properties message: " << result.error();
		}
		}

		void SendStopSendingMessagesMessage() {
		auto init_message = InitMessage{};
		init_message.set_stop_sending_messages(true);
		if (auto result = SendMessage(property_fd, init_message); !result) {
		LOG(ERROR) << "Failed to send load persistent properties message: " << result.error();
		}
		}

		static void HandlePropertyFd() {
		auto message = ReadMessage(property_fd);
		if (!message) {
		LOG(ERROR) << "Could not read message from property service: " << message.error();
		return;
		}

		auto property_message = PropertyMessage{};
		if (!property_message.ParseFromString(*message)) {
		LOG(ERROR) << "Could not parse message from property service";
		return;
		}

		switch (property_message.msg_case()) {
		case PropertyMessage::kControlMessage: {
		auto& control_message = property_message.control_message();
		bool success = HandleControlMessage(control_message.msg(), control_message.name(),
		control_message.pid());

		uint32_t response = success ? PROP_SUCCESS : PROP_ERROR_HANDLE_CONTROL_MESSAGE;
		if (control_message.has_fd()) {
		int fd = control_message.fd();
		TEMP_FAILURE_RETRY(send(fd, &response, sizeof(response), 0));
		close(fd);
		}
		break;
		}
		case PropertyMessage::kChangedMessage: {
		auto& changed_message = property_message.changed_message();
		property_changed(changed_message.name(), changed_message.value());
		break;
		}
		default:
		LOG(ERROR) << "Unknown message type from property service: "
		<< property_message.msg_case();
		}
		}

		int SecondStageMain(int argc, char** argv) {
		if (REBOOT_BOOTLOADER_ON_PANIC) {
		InstallRebootSignalHandlers();
		@@ -685,7 +745,12 @@ int SecondStageMain(int argc, char** argv) {
		UmountDebugRamdisk();
		fs_mgr_vendor_overlay_mount_all();
		export_oem_lock_status();
		StartPropertyService(&epoll);

		StartPropertyService(&property_fd);
		if (auto result = epoll.RegisterHandler(property_fd, HandlePropertyFd); !result) {
		LOG(FATAL) << "Could not register epoll handler for property fd: " << result.error();
		}

		MountHandler mount_handler(&epoll);
		set_usb_controller();

init/init.h

+3 −4

Original line number	Diff line number	Diff line
		@@ -31,16 +31,15 @@ namespace init {
		Parser CreateParser(ActionManager& action_manager, ServiceList& service_list);
		Parser CreateServiceOnlyParser(ServiceList& service_list);

		bool HandleControlMessage(const std::string& msg, const std::string& arg, pid_t pid);

		void property_changed(const std::string& name, const std::string& value);

		bool start_waiting_for_property(const char name, const char value);

		void DumpState();

		void ResetWaitForProp();

		void SendLoadPersistentPropertiesMessage();
		void SendStopSendingMessagesMessage();

		int SecondStageMain(int argc, char** argv);

		} // namespace init

init/property_service.cpp

+156 −72

Original line number	Diff line number	Diff line
		@@ -42,6 +42,7 @@
		#include <map>
		#include <memory>
		#include <mutex>
		#include <optional>
		#include <queue>
		#include <thread>
		#include <vector>
		@@ -63,8 +64,10 @@
		#include "init.h"
		#include "persistent_properties.h"
		#include "property_type.h"
		#include "proto_utils.h"
		#include "selinux.h"
		#include "subcontext.h"
		#include "system/core/init/property_service.pb.h"
		#include "util.h"

		using namespace std::literals;
		@@ -76,6 +79,7 @@ using android::base::StartsWith;
		using android::base::StringPrintf;
		using android::base::Timer;
		using android::base::Trim;
		using android::base::unique_fd;
		using android::base::WriteStringToFile;
		using android::properties::BuildTrie;
		using android::properties::ParsePropertyInfoFile;
		@@ -85,18 +89,13 @@ using android::properties::PropertyInfoEntry;
		namespace android {
		namespace init {

		static constexpr const char kRestoreconProperty[] = "selinux.restorecon_recursive";

		static bool persistent_properties_loaded = false;

		static int property_set_fd = -1;
		static int init_socket = -1;

		static PropertyInfoAreaFile property_info_area;

		uint32_t InitPropertySet(const std::string& name, const std::string& value);

		uint32_t (*property_set)(const std::string& name, const std::string& value) = InitPropertySet;

		void CreateSerializedPropertyInfo();

		struct PropertyAuditData {
		@@ -164,6 +163,17 @@ static bool CheckMacPerms(const std::string& name, const char* target_context,
		return has_access;
		}

		static void SendPropertyChanged(const std::string& name, const std::string& value) {
		auto property_msg = PropertyMessage{};
		auto* changed_message = property_msg.mutable_changed_message();
		changed_message->set_name(name);
		changed_message->set_value(value);

		if (auto result = SendMessage(init_socket, property_msg); !result) {
		LOG(ERROR) << "Failed to send property changed message: " << result.error();
		}
		}

		static uint32_t PropertySet(const std::string& name, const std::string& value, std::string* error) {
		size_t valuelen = value.size();

		@@ -199,7 +209,11 @@ static uint32_t PropertySet(const std::string& name, const std::string& value, s
		if (persistent_properties_loaded && StartsWith(name, "persist.")) {
		WritePersistentProperty(name, value);
		}
		property_changed(name, value);
		// If init hasn't started its main loop, then it won't be handling property changed messages
		// anyway, so there's no need to try to send them.
		if (init_socket != -1) {
		SendPropertyChanged(name, value);
		}
		return PROP_SUCCESS;
		}

		@@ -239,35 +253,10 @@ class AsyncRestorecon {
		bool thread_started_ = false;
		};

		uint32_t InitPropertySet(const std::string& name, const std::string& value) {
		if (StartsWith(name, "ctl.")) {
		LOG(ERROR) << "InitPropertySet: Do not set ctl. properties from init; call the Service "
		"functions directly";
		return PROP_ERROR_INVALID_NAME;
		}
		if (name == kRestoreconProperty) {
		LOG(ERROR) << "InitPropertySet: Do not set '" << kRestoreconProperty
		<< "' from init; use the restorecon builtin directly";
		return PROP_ERROR_INVALID_NAME;
		}

		uint32_t result = 0;
		ucred cr = {.pid = 1, .uid = 0, .gid = 0};
		std::string error;
		result = HandlePropertySet(name, value, kInitContext.c_str(), cr, &error);
		if (result != PROP_SUCCESS) {
		LOG(ERROR) << "Init cannot set '" << name << "' to '" << value << "': " << error;
		}

		return result;
		}

		class SocketConnection {
		public:
		SocketConnection(int socket, const ucred& cred) : socket_(socket), cred_(cred) {}

		~SocketConnection() { close(socket_); }

		bool RecvUint32(uint32_t* value, uint32_t* timeout_ms) {
		return RecvFully(value, sizeof(*value), timeout_ms);
		}
		@@ -304,6 +293,9 @@ class SocketConnection {
		}

		bool SendUint32(uint32_t value) {
		if (!socket_.ok()) {
		return true;
		}
		int result = TEMP_FAILURE_RETRY(send(socket_, &value, sizeof(value), 0));
		return result == sizeof(value);
		}
		@@ -318,7 +310,7 @@ class SocketConnection {
		return true;
		}

		int socket() { return socket_; }
		[[nodiscard]] int Release() { return socket_.release(); }

		const ucred& cred() { return cred_; }

		@@ -389,12 +381,46 @@ class SocketConnection {
		return bytes_left == 0;
		}

		int socket_;
		unique_fd socket_;
		ucred cred_;

		DISALLOW_IMPLICIT_CONSTRUCTORS(SocketConnection);
		};

		static uint32_t SendControlMessage(const std::string& msg, const std::string& name, pid_t pid,
		SocketConnection* socket, std::string* error) {
		if (init_socket == -1) {
		*error = "Received control message after shutdown, ignoring";
		return PROP_ERROR_HANDLE_CONTROL_MESSAGE;
		}

		auto property_msg = PropertyMessage{};
		auto* control_message = property_msg.mutable_control_message();
		control_message->set_msg(msg);
		control_message->set_name(name);
		control_message->set_pid(pid);

		// We must release the fd before sending it to init, otherwise there will be a race with init.
		// If init calls close() before Release(), then fdsan will see the wrong tag and abort().
		int fd = -1;
		if (socket != nullptr) {
		fd = socket->Release();
		control_message->set_fd(fd);
		}

		if (auto result = SendMessage(init_socket, property_msg); !result) {
		// We've already released the fd above, so if we fail to send the message to init, we need
		// to manually free it here.
		if (fd != -1) {
		close(fd);
		}
		*error = "Failed to send control message: " + result.error().message();
		return PROP_ERROR_HANDLE_CONTROL_MESSAGE;
		}

		return PROP_SUCCESS;
		}

		bool CheckControlPropertyPerms(const std::string& name, const std::string& value,
		const std::string& source_context, const ucred& cr) {
		// We check the legacy method first but these properties are dontaudit, so we only log an audit
		@@ -462,15 +488,14 @@ uint32_t CheckPermissions(const std::string& name, const std::string& value,

		// This returns one of the enum of PROP_SUCCESS or PROP_ERROR*.
		uint32_t HandlePropertySet(const std::string& name, const std::string& value,
		const std::string& source_context, const ucred& cr, std::string* error) {
		const std::string& source_context, const ucred& cr,
		SocketConnection* socket, std::string* error) {
		if (auto ret = CheckPermissions(name, value, source_context, cr, error); ret != PROP_SUCCESS) {
		return ret;
		}

		if (StartsWith(name, "ctl.")) {
		return HandleControlMessage(name.c_str() + 4, value, cr.pid)
		? PROP_SUCCESS
		: PROP_ERROR_HANDLE_CONTROL_MESSAGE;
		return SendControlMessage(name.c_str() + 4, value, cr.pid, socket, error);
		}

		// sys.powerctl is a special property that is used to make the device reboot. We want to log
		@@ -501,6 +526,20 @@ uint32_t HandlePropertySet(const std::string& name, const std::string& value,
		return PropertySet(name, value, error);
		}

		uint32_t InitPropertySet(const std::string& name, const std::string& value) {
		uint32_t result = 0;
		ucred cr = {.pid = 1, .uid = 0, .gid = 0};
		std::string error;
		result = HandlePropertySet(name, value, kInitContext.c_str(), cr, nullptr, &error);
		if (result != PROP_SUCCESS) {
		LOG(ERROR) << "Init cannot set '" << name << "' to '" << value << "': " << error;
		}

		return result;
		}

		uint32_t (*property_set)(const std::string& name, const std::string& value) = InitPropertySet;

		static void handle_property_set_fd() {
		static constexpr uint32_t kDefaultSocketTimeout = 2000; /* ms */

		@@ -549,7 +588,8 @@ static void handle_property_set_fd() {

		const auto& cr = socket.cred();
		std::string error;
		uint32_t result = HandlePropertySet(prop_name, prop_value, source_context, cr, &error);
		uint32_t result =
		HandlePropertySet(prop_name, prop_value, source_context, cr, nullptr, &error);
		if (result != PROP_SUCCESS) {
		LOG(ERROR) << "Unable to set property '" << prop_name << "' from uid:" << cr.uid
		<< " gid:" << cr.gid << " pid:" << cr.pid << ": " << error;
		@@ -577,7 +617,7 @@ static void handle_property_set_fd() {

		const auto& cr = socket.cred();
		std::string error;
		uint32_t result = HandlePropertySet(name, value, source_context, cr, &error);
		uint32_t result = HandlePropertySet(name, value, source_context, cr, &socket, &error);
		if (result != PROP_SUCCESS) {
		LOG(ERROR) << "Unable to set property '" << name << "' from uid:" << cr.uid
		<< " gid:" << cr.gid << " pid:" << cr.pid << ": " << error;
		@@ -741,33 +781,6 @@ static void load_override_properties() {
		}
		}

		/* When booting an encrypted system, /data is not mounted when the
		* property service is started, so any properties stored there are
		* not loaded. Vold triggers init to load these properties once it
		* has mounted /data.
		*/
		void load_persist_props(void) {
		// Devices with FDE have load_persist_props called twice; the first time when the temporary
		// /data partition is mounted and then again once /data is truly mounted. We do not want to
		// read persistent properties from the temporary /data partition or mark persistent properties
		// as having been loaded during the first call, so we return in that case.
		std::string crypto_state = android::base::GetProperty("ro.crypto.state", "");
		std::string crypto_type = android::base::GetProperty("ro.crypto.type", "");
		if (crypto_state == "encrypted" && crypto_type == "block") {
		static size_t num_calls = 0;
		if (++num_calls == 1) return;
		}

		load_override_properties();
		/* Read persistent properties after all default values have been loaded. */
		auto persistent_properties = LoadPersistentProperties();
		for (const auto& persistent_property_record : persistent_properties.properties()) {
		property_set(persistent_property_record.name(), persistent_property_record.value());
		}
		persistent_properties_loaded = true;
		property_set("ro.persistent_properties.ready", "true");
		}

		// If the ro.product.[brand\|device\|manufacturer\|model\|name] properties have not been explicitly
		// set, derive them from ro.product.${partition}.* properties
		static void property_initialize_ro_product_props() {
		@@ -985,21 +998,92 @@ void CreateSerializedPropertyInfo() {
		selinux_android_restorecon(kPropertyInfosPath, 0);
		}

		void StartPropertyService(Epoll* epoll) {
		static void HandleInitSocket() {
		auto message = ReadMessage(init_socket);
		if (!message) {
		LOG(ERROR) << "Could not read message from init_dedicated_recv_socket: " << message.error();
		return;
		}

		auto init_message = InitMessage{};
		if (!init_message.ParseFromString(*message)) {
		LOG(ERROR) << "Could not parse message from init";
		return;
		}

		switch (init_message.msg_case()) {
		case InitMessage::kLoadPersistentProperties: {
		load_override_properties();
		// Read persistent properties after all default values have been loaded.
		auto persistent_properties = LoadPersistentProperties();
		for (const auto& persistent_property_record : persistent_properties.properties()) {
		InitPropertySet(persistent_property_record.name(),
		persistent_property_record.value());
		}
		InitPropertySet("ro.persistent_properties.ready", "true");
		persistent_properties_loaded = true;
		break;
		}
		case InitMessage::kStopSendingMessages: {
		init_socket = -1;
		break;
		}
		default:
		LOG(ERROR) << "Unknown message type from init: " << init_message.msg_case();
		}
		}

		static void PropertyServiceThread() {
		Epoll epoll;
		if (auto result = epoll.Open(); !result) {
		LOG(FATAL) << result.error();
		}

		if (auto result = epoll.RegisterHandler(property_set_fd, handle_property_set_fd); !result) {
		LOG(FATAL) << result.error();
		}

		if (auto result = epoll.RegisterHandler(init_socket, HandleInitSocket); !result) {
		LOG(FATAL) << result.error();
		}

		while (true) {
		auto pending_functions = epoll.Wait(std::nullopt);
		if (!pending_functions) {
		LOG(ERROR) << pending_functions.error();
		} else {
		for (const auto& function : *pending_functions) {
		(*function)();
		}
		}
		}
		}

		void StartPropertyService(int* epoll_socket) {
		property_set("ro.property_service.version", "2");

		int sockets[2];
		if (socketpair(AF_UNIX, SOCK_SEQPACKET \| SOCK_CLOEXEC, 0, sockets) != 0) {
		PLOG(FATAL) << "Failed to socketpair() between property_service and init";
		}
		*epoll_socket = sockets[0];
		init_socket = sockets[1];

		if (auto result = CreateSocket(PROP_SERVICE_NAME, SOCK_STREAM \| SOCK_CLOEXEC \| SOCK_NONBLOCK,
		false, 0666, 0, 0, {})) {
		property_set_fd = *result;
		} else {
		PLOG(FATAL) << "start_property_service socket creation failed: " << result.error();
		LOG(FATAL) << "start_property_service socket creation failed: " << result.error();
		}

		listen(property_set_fd, 8);

		if (auto result = epoll->RegisterHandler(property_set_fd, handle_property_set_fd); !result) {
		PLOG(FATAL) << result.error();
		}
		std::thread{PropertyServiceThread}.detach();

		property_set = [](const std::string& key, const std::string& value) -> uint32_t {
		android::base::SetProperty(key, value);
		return 0;
		};
		}

		} // namespace init