Merge "RESTRICT AUTOMERGE: Added an app id security check in isAppForeground." into oc-dev am: 546ba589a2

am: 84376cb95a

Change-Id: I096470de6d03ab34591b12bc7172056a1ffe38ed

core/java/android/os/UserHandle.java

@@ -131,6 +131,19 @@ public final class UserHandle implements Parcelable {
         }
     }
 
+    /**
+     * Whether a UID belongs to a system core component or not.
+     * @hide
+     */
+    public static boolean isCore(int uid) {
+        if (uid >= 0) {
+            final int appId = getAppId(uid);
+            return appId < Process.FIRST_APPLICATION_UID;
+        } else {
+            return false;
+        }
+    }
+
     /**
      * Returns the user for a given uid.
      * @param uid A uid for an application running in a particular user.

services/core/java/com/android/server/am/ActivityManagerService.java

@@ -8021,6 +8021,14 @@ public class ActivityManagerService extends IActivityManager.Stub
 
     @Override
     public boolean isAppForeground(int uid) throws RemoteException {
+        int callerUid = Binder.getCallingUid();
+        if (UserHandle.isCore(callerUid) || callerUid == uid) {
+            return isAppForegroundInternal(uid);
+        }
+        return false;
+    }
+
+    private boolean isAppForegroundInternal(int uid) {
         synchronized (this) {
             UidRecord uidRec = mActiveUids.get(uid);
             if (uidRec == null || uidRec.idle) {