Merge "Limit the number of MediaSessions per uid" (0acee601) · Commits · e / os / android_frameworks_base

media/java/android/media/session/MediaSession.java

+4 −0

Original line number	Diff line number	Diff line
		@@ -146,6 +146,8 @@ public final class MediaSession {
		* the system but will not be published until {@link #setActive(boolean)
		* setActive(true)} is called. You must call {@link #release()} when
		* finished with the session.
		* <p>
		* Note that {@link RuntimeException} will be thrown if an app creates too many sessions.
		*
		* @param context The context to use to create the session.
		* @param tag A short name for debugging purposes.
		@@ -163,6 +165,8 @@ public final class MediaSession {
		* The {@code sessionInfo} can include additional unchanging information about this session.
		* For example, it can include the version of the application, or the list of the custom
		* commands that this session supports.
		* <p>
		* Note that {@link RuntimeException} will be thrown if an app creates too many sessions.
		*
		* @param context The context to use to create the session.
		* @param tag A short name for debugging purposes.

services/core/java/com/android/server/media/MediaSessionService.java

+36 −14

Original line number	Diff line number	Diff line
		@@ -103,6 +103,7 @@ public class MediaSessionService extends SystemService implements Monitor {

		private static final int WAKELOCK_TIMEOUT = 5000;
		private static final int MEDIA_KEY_LISTENER_TIMEOUT = 1000;
		private static final int SESSION_CREATION_LIMIT_PER_UID = 100;

		private final Context mContext;
		private final SessionManagerImpl mSessionManagerImpl;
		@@ -428,6 +429,18 @@ public class MediaSessionService extends SystemService implements Monitor {
		Log.d(TAG, "Destroying " + session);
		}
		FullUserRecord user = getFullUserRecordLocked(session.getUserId());

		if (user != null) {
		final int uid = session.getUid();
		final int sessionCount = user.mUidToSessionCount.get(uid, 0);
		if (sessionCount <= 0) {
		Log.w(TAG, "destroySessionLocked: sessionCount should be positive. "
		+ "sessionCount=" + sessionCount);
		} else {
		user.mUidToSessionCount.put(uid, sessionCount - 1);
		}
		}

		if (mGlobalPrioritySession == session) {
		mGlobalPrioritySession = null;
		if (session.isActive() && user != null) {
		@@ -490,6 +503,20 @@ public class MediaSessionService extends SystemService implements Monitor {
		}
		}

		private boolean hasMediaControlPermission(int pid, int uid) {
		// Check if it's system server or has MEDIA_CONTENT_CONTROL.
		// Note that system server doesn't have MEDIA_CONTENT_CONTROL, so we need extra
		// check here.
		if (uid == Process.SYSTEM_UID \|\| mContext.checkPermission(
		android.Manifest.permission.MEDIA_CONTENT_CONTROL, pid, uid)
		== PackageManager.PERMISSION_GRANTED) {
		return true;
		} else if (DEBUG) {
		Log.d(TAG, "uid(" + uid + ") hasn't granted MEDIA_CONTENT_CONTROL");
		}
		return false;
		}

		/**
		* This checks if the component is an enabled notification listener for the
		* specified user. Enabled components may only operate on behalf of the user
		@@ -544,6 +571,14 @@ public class MediaSessionService extends SystemService implements Monitor {
		throw new RuntimeException("Media Session owner died prematurely.", e);
		}

		final int sessionCount = user.mUidToSessionCount.get(callerUid, 0);
		if (sessionCount >= SESSION_CREATION_LIMIT_PER_UID
		&& !hasMediaControlPermission(callerPid, callerUid)) {
		throw new RuntimeException("Created too many sessions. count="
		+ sessionCount + ")");
		}
		user.mUidToSessionCount.put(callerUid, sessionCount + 1);

		user.mPriorityStack.addSession(session);
		mHandler.postSessionsChanged(session);

		@@ -723,6 +758,7 @@ public class MediaSessionService extends SystemService implements Monitor {
		mOnMediaKeyEventDispatchedListeners = new HashMap<>();
		private final HashMap<IBinder, OnMediaKeyEventSessionChangedListenerRecord>
		mOnMediaKeyEventSessionChangedListeners = new HashMap<>();
		private final SparseIntArray mUidToSessionCount = new SparseIntArray();

		private PendingIntent mLastMediaButtonReceiver;
		private ComponentName mRestoredMediaButtonReceiver;
		@@ -1954,20 +1990,6 @@ public class MediaSessionService extends SystemService implements Monitor {
		return resolvedUserId;
		}

		private boolean hasMediaControlPermission(int pid, int uid) {
		// Check if it's system server or has MEDIA_CONTENT_CONTROL.
		// Note that system server doesn't have MEDIA_CONTENT_CONTROL, so we need extra
		// check here.
		if (uid == Process.SYSTEM_UID \|\| mContext.checkPermission(
		android.Manifest.permission.MEDIA_CONTENT_CONTROL, pid, uid)
		== PackageManager.PERMISSION_GRANTED) {
		return true;
		} else if (DEBUG) {
		Log.d(TAG, "uid(" + uid + ") hasn't granted MEDIA_CONTENT_CONTROL");
		}
		return false;
		}

		private boolean hasEnabledNotificationListener(int resolvedUserId, String packageName)
		throws RemoteException {
		// You may not access another user's content as an enabled listener.