Commit 18424bb7 authored Jun 07, 2018 by Jean-Michel Trivi Committed by android-build-team Robot Jun 12, 2018

AudioService: fix deallock setBluetoothScoOn vs setMode

In AudioService:
setBluetoothScoOn()
  > setBluetoothScoOnInt()
     > synchronized(mSettingsLock)
     > muteRingerModeStreams()
	> synchronized (VolumeStreamState.class)
vs
setMode()
  > setModeInt()
     > synchronized (mSettingsLock)
        > synchronized (VolumeStreamState.class)

The issue comes from setBluetoothScoOnInt() releasing the lock
  on mSettingsLock before calling muteRingerModeStreams(). This
  breaks the expected lock ordering in AudioService, where
  mSettingsLock must be locked before VolumeStreamState.class.

Bug: 109746821
Test: see bug
Change-Id: I853ca60781efc506626b6345f27da701655ac359
(cherry picked from commit c106d9f9)

parent b96cfb97

services/core/java/com/android/server/audio/AudioService.java

+2 −2

Original line number	Diff line number	Diff line
		@@ -2623,6 +2623,7 @@ public class AudioService extends IAudioService.Stub
		broadcastRingerMode(AudioManager.RINGER_MODE_CHANGED_ACTION, ringerMode);
		}

		@GuardedBy("mSettingsLock")
		private void muteRingerModeStreams() {
		// Mute stream if not previously muted by ringer mode and (ringer mode
		// is not RINGER_MODE_NORMAL OR stream is zen muted) and stream is affected by ringer mode.
		@@ -2710,9 +2711,8 @@ public class AudioService extends IAudioService.Stub
		synchronized(mSettingsLock) {
		change = mRingerMode != ringerMode;
		mRingerMode = ringerMode;
		}

		muteRingerModeStreams();
		}

		// Post a persist ringer mode msg
		if (persist) {