Log pid for writes to sys.powerctl
Unless a process logs that it is requesting a device to reboot, there
are no logs to show which process triggered a reboot. This change
introduces such a log in property service such that system initiated
reboots can be clearly blamed back to a calling process.
Bug: 64214361
Test: reboot and check kernel log for reboot string
Change-Id: I18de33d2a0933d20bdb581025b78020c88c5c6eb
diff --git a/init/property_service.cpp b/init/property_service.cpp
index 8c592cb..5f5ed40 100644
--- a/init/property_service.cpp
+++ b/init/property_service.cpp
@@ -45,6 +45,7 @@
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/properties.h>
+#include <android-base/stringprintf.h>
#include <android-base/strings.h>
#include <bootimg.h>
#include <fs_mgr.h>
@@ -56,6 +57,7 @@
#include "persistent_properties.h"
#include "util.h"
+using android::base::StringPrintf;
using android::base::Timer;
#define RECOVERY_MOUNT_POINT "/recovery"
@@ -418,6 +420,20 @@
}
} else {
if (check_mac_perms(name, source_ctx, &cr)) {
+ // sys.powerctl is a special property that is used to make the device reboot. We want to log
+ // any process that sets this property to be able to accurately blame the cause of a shutdown.
+ if (name == "sys.powerctl") {
+ std::string cmdline_path = StringPrintf("proc/%d/cmdline", cr.pid);
+ std::string process_cmdline;
+ std::string process_log_string;
+ if (android::base::ReadFileToString(cmdline_path, &process_cmdline)) {
+ // Since cmdline is null deliminated, .c_str() conveniently gives us just the process path.
+ process_log_string = StringPrintf(" (%s)", process_cmdline.c_str());
+ }
+ LOG(INFO) << "Received sys.powerctl='" << value << "' from pid: " << cr.pid
+ << process_log_string;
+ }
+
uint32_t result = property_set(name, value);
if (!legacy_protocol) {
socket.SendUint32(result);