commit 028cf0973f928503e89124c3f6493a5226826ed9
author Pawin Vongmasa <pawin@google.com> Tue Dec 12 01:56:40 2017 -0800
committer Pawin Vongmasa <pawin@google.com> Thu Dec 14 16:29:26 2017 +0000
tree d726b12d56f9b32a7fc29667c0be3c3e558cae7c
parent 97eb375c515ab9cf7ad8e23b678b32f279059139

Prevent MediaPlayerService::Client's use-after-free

Test: make cts -j123 && cts-tradefed run cts-dev -m \
CtsMediaTestCases --compatibility:module-arg \
CtsMediaTestCases:include-annotation:\
android.platform.test.annotations.RequiresDevice

Bug: 70546581
Merged-In: Ia142a7735c6685eb67b2c00917c0ed5ea7e0da9e
Change-Id: Ia142a7735c6685eb67b2c00917c0ed5ea7e0da9e
(cherry picked from commit d27ad6bae3215db0ed174f5f036339c9515fbba7)

media/libmediaplayerservice/include/MediaPlayerInterface.h

diff --git a/media/libmediaplayerservice/include/MediaPlayerInterface.h b/media/libmediaplayerservice/include/MediaPlayerInterface.h
index a01f7f2..c21ef42 100644
--- a/media/libmediaplayerservice/include/MediaPlayerInterface.h
+++ b/media/libmediaplayerservice/include/MediaPlayerInterface.h
@@ -67,7 +67,7 @@
 #define AUDIO_SINK_MIN_DEEP_BUFFER_DURATION_US 5000000
 
 // callback mechanism for passing messages to MediaPlayer object
-typedef void (*notify_callback_f)(void* cookie,
+typedef void (*notify_callback_f)(const wp<IMediaPlayer> &listener,
         int msg, int ext1, int ext2, const Parcel *obj);
 
 // abstract base class - use MediaPlayerInterface
@@ -152,7 +152,7 @@
         virtual sp<VolumeShaper::State> getVolumeShaperState(int id);
     };
 
-                        MediaPlayerBase() : mCookie(0), mNotify(0) {}
+                        MediaPlayerBase() : mClient(0), mNotify(0) {}
     virtual             ~MediaPlayerBase() {}
     virtual status_t    initCheck() = 0;
     virtual bool        hardwareOutput() = 0;
@@ -263,22 +263,22 @@
     };
 
     void        setNotifyCallback(
-            void* cookie, notify_callback_f notifyFunc) {
+            const wp<IMediaPlayer> &client, notify_callback_f notifyFunc) {
         Mutex::Autolock autoLock(mNotifyLock);
-        mCookie = cookie; mNotify = notifyFunc;
+        mClient = client; mNotify = notifyFunc;
     }
 
     void        sendEvent(int msg, int ext1=0, int ext2=0,
                           const Parcel *obj=NULL) {
         notify_callback_f notifyCB;
-        void* cookie;
+        wp<IMediaPlayer> client;
         {
             Mutex::Autolock autoLock(mNotifyLock);
             notifyCB = mNotify;
-            cookie = mCookie;
+            client = mClient;
         }
 
-        if (notifyCB) notifyCB(cookie, msg, ext1, ext2, obj);
+        if (notifyCB) notifyCB(client, msg, ext1, ext2, obj);
     }
 
     virtual status_t dump(int /* fd */, const Vector<String16>& /* args */) const {
@@ -297,7 +297,7 @@
     friend class MediaPlayerService;
 
     Mutex               mNotifyLock;
-    void*               mCookie;
+    wp<IMediaPlayer>    mClient;
     notify_callback_f   mNotify;
 };