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Merge "Listen on property_service_for_system socket for powerctl messages" into main

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This commit is contained in:
Treehugger Robot 2023-07-19 22:18:07 +00:00 • committed by Android (Google) Code Review
commit 11e2ebbc53
1 changed files with 63 additions and 47 deletions
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110
init/property_service.cpp
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@ -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) {
@ -394,31 +395,37 @@ static std::optional<uint32_t> PropertySet(const std::string& name, const std::s
return {PROP_ERROR_INVALID_VALUE};
}
prop_info* pi = (prop_info*)__system_property_find(name.c_str());
if (pi != nullptr) {
// ro.* properties are actually "write-once".
if (StartsWith(name, "ro.")) {
*error = "Read-only property was already set";
return {PROP_ERROR_READ_ONLY_PROPERTY};
}
__system_property_update(pi, value.c_str(), valuelen);
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 {
int rc = __system_property_add(name.c_str(), name.size(), value.c_str(), valuelen);
if (rc < 0) {
*error = "__system_property_add failed";
return {PROP_ERROR_SET_FAILED};
}
}
prop_info* pi = (prop_info*)__system_property_find(name.c_str());
if (pi != nullptr) {
// ro.* properties are actually "write-once".
if (StartsWith(name, "ro.")) {
*error = "Read-only property was already set";
return {PROP_ERROR_READ_ONLY_PROPERTY};
}
// Don't write properties to disk until after we have read all default
// properties to prevent them from being overwritten by default values.
if (socket && persistent_properties_loaded && StartsWith(name, "persist.")) {
if (persist_write_thread) {
persist_write_thread->Write(name, value, std::move(*socket));
return {};
__system_property_update(pi, value.c_str(), valuelen);
} else {
int rc = __system_property_add(name.c_str(), name.size(), value.c_str(), valuelen);
if (rc < 0) {
*error = "__system_property_add failed";
return {PROP_ERROR_SET_FAILED};
}
}
// Don't write properties to disk until after we have read all default
// properties to prevent them from being overwritten by default values.
if (socket && persistent_properties_loaded && StartsWith(name, "persist.")) {
if (persist_write_thread) {
persist_write_thread->Write(name, value, std::move(*socket));
return {};
}
WritePersistentProperty(name, value);
}
WritePersistentProperty(name, value);
}
NotifyPropertyChange(name, value);
@ -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;
}
@ -1419,19 +1426,21 @@ 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 (auto result = epoll.RegisterHandler(init_socket, HandleInitSocket); !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) {
@ -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);