Merge "Pass the correct user ID to SetProcessProfilesCached()" into main
diff --git a/core/jni/android_util_Process.cpp b/core/jni/android_util_Process.cpp
index 7af69f2..6a640a5 100644
--- a/core/jni/android_util_Process.cpp
+++ b/core/jni/android_util_Process.cpp
@@ -28,6 +28,7 @@
#include <meminfo/sysmeminfo.h>
#include <processgroup/processgroup.h>
#include <processgroup/sched_policy.h>
+#include <android-base/logging.h>
#include <android-base/unique_fd.h>
#include <algorithm>
@@ -232,6 +233,31 @@
}
}
+// Look up the user ID of a process in /proc/${pid}/status. The Uid: line is present in
+// /proc/${pid}/status since at least kernel v2.5.
+static int uid_from_pid(int pid)
+{
+ int uid = -1;
+ std::array<char, 64> path;
+ int res = snprintf(path.data(), path.size(), "/proc/%d/status", pid);
+ if (res < 0 || res >= static_cast<int>(path.size())) {
+ DCHECK(false);
+ return uid;
+ }
+ FILE* f = fopen(path.data(), "r");
+ if (!f) {
+ return uid;
+ }
+ char line[256];
+ while (fgets(line, sizeof(line), f)) {
+ if (sscanf(line, "Uid: %d", &uid) == 1) {
+ break;
+ }
+ }
+ fclose(f);
+ return uid;
+}
+
void android_os_Process_setProcessGroup(JNIEnv* env, jobject clazz, int pid, jint grp)
{
ALOGV("%s pid=%d grp=%" PRId32, __func__, pid, grp);
@@ -275,7 +301,12 @@
}
}
- if (!SetProcessProfilesCached(0, pid, {get_cpuset_policy_profile_name((SchedPolicy)grp)}))
+ const int uid = uid_from_pid(pid);
+ if (uid < 0) {
+ signalExceptionForGroupError(env, ESRCH, pid);
+ return;
+ }
+ if (!SetProcessProfilesCached(uid, pid, {get_cpuset_policy_profile_name((SchedPolicy)grp)}))
signalExceptionForGroupError(env, errno ? errno : EPERM, pid);
}