Merge "Listen on property_service_for_system socket for powerctl messages" into main (11e2ebbc) · Commits · e / os / android_system_core

init/property_service.cpp

+62 −46

Original line number	Diff line number	Diff line
		@@ -57,12 +57,12 @@
		#include <android-base/result.h>
		#include <android-base/stringprintf.h>
		#include <android-base/strings.h>
		#include <private/android_filesystem_config.h>
		#include <property_info_parser/property_info_parser.h>
		#include <property_info_serializer/property_info_serializer.h>
		#include <selinux/android.h>
		#include <selinux/label.h>
		#include <selinux/selinux.h>

		#include "debug_ramdisk.h"
		#include "epoll.h"
		#include "init.h"
		@@ -111,12 +111,13 @@ constexpr auto API_LEVEL_CURRENT = 10000;

		static bool persistent_properties_loaded = false;

		static int property_set_fd = -1;
		static int from_init_socket = -1;
		static int init_socket = -1;
		static bool accept_messages = false;
		static std::mutex accept_messages_lock;
		static std::mutex selinux_check_access_lock;
		static std::thread property_service_thread;
		static std::thread property_service_for_system_thread;

		static std::unique_ptr<PersistWriteThread> persist_write_thread;

		@@ -161,6 +162,7 @@ bool CanReadProperty(const std::string& source_context, const std::string& name)
		ucred cr = {.pid = 0, .uid = 0, .gid = 0};
		audit_data.cr = &cr;

		auto lock = std::lock_guard{selinux_check_access_lock};
		return selinux_check_access(source_context.c_str(), target_context, "file", "read",
		&audit_data) == 0;
		}
		@@ -176,10 +178,9 @@ static bool CheckMacPerms(const std::string& name, const char* target_context,
		audit_data.name = name.c_str();
		audit_data.cr = &cr;

		bool has_access = (selinux_check_access(source_context, target_context, "property_service",
		"set", &audit_data) == 0);

		return has_access;
		auto lock = std::lock_guard{selinux_check_access_lock};
		return selinux_check_access(source_context, target_context, "property_service", "set",
		&audit_data) == 0;
		}

		void NotifyPropertyChange(const std::string& name, const std::string& value) {
		@@ -394,6 +395,11 @@ static std::optional<uint32_t> PropertySet(const std::string& name, const std::s
		return {PROP_ERROR_INVALID_VALUE};
		}

		if (name == "sys.powerctl") {
		// No action here - NotifyPropertyChange will trigger the appropriate action, and since this
		// can come to the second thread, we mustn't call out to the __system_property_* functions
		// which support multiple readers but only one mutator.
		} else {
		prop_info* pi = (prop_info*)__system_property_find(name.c_str());
		if (pi != nullptr) {
		// ro.* properties are actually "write-once".
		@@ -420,6 +426,7 @@ static std::optional<uint32_t> PropertySet(const std::string& name, const std::s
		}
		WritePersistentProperty(name, value);
		}
		}

		NotifyPropertyChange(name, value);
		return {PROP_SUCCESS};
		@@ -579,10 +586,10 @@ uint32_t HandlePropertySetNoSocket(const std::string& name, const std::string& v
		return *ret;
		}

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

		int s = accept4(property_set_fd, nullptr, nullptr, SOCK_CLOEXEC);
		int s = accept4(fd, nullptr, nullptr, SOCK_CLOEXEC);
		if (s == -1) {
		return;
		}
		@@ -1419,20 +1426,22 @@ static void HandleInitSocket() {
		}
		}

		static void PropertyServiceThread() {
		static void PropertyServiceThread(int fd, bool listen_init) {
		Epoll epoll;
		if (auto result = epoll.Open(); !result.ok()) {
		LOG(FATAL) << result.error();
		}

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

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

		while (true) {
		auto epoll_result = epoll.Wait(std::nullopt);
		@@ -1482,6 +1491,23 @@ void PersistWriteThread::Write(std::string name, std::string value, SocketConnec
		cv_.notify_all();
		}

		void StartThread(const char* name, int mode, int gid, std::thread& t, bool listen_init) {
		int fd = -1;
		if (auto result = CreateSocket(name, SOCK_STREAM \| SOCK_CLOEXEC \| SOCK_NONBLOCK,
		/passcred=/false, /should_listen=/false, mode, /uid=/0,
		/gid=/gid, /socketcon=/{});
		result.ok()) {
		fd = *result;
		} else {
		LOG(FATAL) << "start_property_service socket creation failed: " << result.error();
		}

		listen(fd, 8);

		auto new_thread = std::thread(PropertyServiceThread, fd, listen_init);
		t.swap(new_thread);
		}

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

		@@ -1493,19 +1519,9 @@ void StartPropertyService(int* epoll_socket) {
		init_socket = sockets[1];
		StartSendingMessages();

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

		listen(property_set_fd, 8);

		auto new_thread = std::thread{PropertyServiceThread};
		property_service_thread.swap(new_thread);
		StartThread(PROP_SERVICE_FOR_SYSTEM_NAME, 0660, AID_SYSTEM, property_service_for_system_thread,
		true);
		StartThread(PROP_SERVICE_NAME, 0666, 0, property_service_thread, false);

		auto async_persist_writes =
		android::base::GetBoolProperty("ro.property_service.async_persist_writes", false);