DO NOT MERGE
Verify URI permissions in MediaMetadata

Add a check for URI permission to make sure that user can access the URI
set in MediaMetadata. If permission is denied, clear the URI string set
in metadata.

Bug: 271851153
Test: atest MediaSessionTest
Test: Verified by POC app attached in bug, image of second user is not
the UMO background of the first user.
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:277e7e05866a3da3c5871c071231b2b7c911d81e)
Merged-In: I932d5d5143998db89d7132ced84faffa4a0bd5aa
Change-Id: I932d5d5143998db89d7132ced84faffa4a0bd5aa

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

diff --git a/services/core/java/com/android/server/media/MediaSessionRecord.java b/services/core/java/com/android/server/media/MediaSessionRecord.java
index cc4895f..b459cfe 100644
--- a/services/core/java/com/android/server/media/MediaSessionRecord.java
+++ b/services/core/java/com/android/server/media/MediaSessionRecord.java
@@ -22,6 +22,8 @@
 import android.annotation.RequiresPermission;
 import android.app.PendingIntent;
 import android.content.ComponentName;
+import android.content.ContentProvider;
+import android.content.ContentResolver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
@@ -63,6 +65,9 @@
 import android.util.Log;
 import android.view.KeyEvent;
 
+import com.android.server.LocalServices;
+import com.android.server.uri.UriGrantsManagerInternal;
+
 import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -78,6 +83,10 @@
 // TODO(jaewan): Do not call service method directly -- introduce listener instead.
 public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionRecordImpl {
     private static final String TAG = "MediaSessionRecord";
+    private static final String[] ART_URIS = new String[] {
+            MediaMetadata.METADATA_KEY_ALBUM_ART_URI,
+            MediaMetadata.METADATA_KEY_ART_URI,
+            MediaMetadata.METADATA_KEY_DISPLAY_ICON_URI};
     private static final boolean DEBUG = Log.isLoggable(TAG, Log.DEBUG);
 
     /**
@@ -131,6 +140,7 @@
     private final SessionStub mSession;
     private final SessionCb mSessionCb;
     private final MediaSessionService mService;
+    private final UriGrantsManagerInternal mUgmInternal;
     private final Context mContext;
     private final boolean mVolumeAdjustmentForRemoteGroupSessions;
 
@@ -192,6 +202,7 @@
         mAudioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
         mAudioAttrs = DEFAULT_ATTRIBUTES;
         mPolicies = policies;
+        mUgmInternal = LocalServices.getService(UriGrantsManagerInternal.class);
         mVolumeAdjustmentForRemoteGroupSessions = mContext.getResources().getBoolean(
                 com.android.internal.R.bool.config_volumeAdjustmentForRemoteGroupSessions);
 
@@ -1018,21 +1029,45 @@
         public void setMetadata(MediaMetadata metadata, long duration, String metadataDescription)
                 throws RemoteException {
             synchronized (mLock) {
-                MediaMetadata temp = metadata == null ? null : new MediaMetadata.Builder(metadata)
-                        .build();
-                // This is to guarantee that the underlying bundle is unparceled
-                // before we set it to prevent concurrent reads from throwing an
-                // exception
-                if (temp != null) {
-                    temp.size();
-                }
-                mMetadata = temp;
                 mDuration = duration;
                 mMetadataDescription = metadataDescription;
+                mMetadata = sanitizeMediaMetadata(metadata);
             }
             mHandler.post(MessageHandler.MSG_UPDATE_METADATA);
         }
 
+        private MediaMetadata sanitizeMediaMetadata(MediaMetadata metadata) {
+            if (metadata == null) {
+                return null;
+            }
+            MediaMetadata.Builder metadataBuilder = new MediaMetadata.Builder(metadata);
+            for (String key: ART_URIS) {
+                String uriString = metadata.getString(key);
+                if (TextUtils.isEmpty(uriString)) {
+                    continue;
+                }
+                Uri uri = Uri.parse(uriString);
+                if (!ContentResolver.SCHEME_CONTENT.equals(uri.getScheme())) {
+                    continue;
+                }
+                try {
+                    mUgmInternal.checkGrantUriPermission(getUid(),
+                            getPackageName(),
+                            ContentProvider.getUriWithoutUserId(uri),
+                            Intent.FLAG_GRANT_READ_URI_PERMISSION,
+                            ContentProvider.getUserIdFromUri(uri, getUserId()));
+                } catch (SecurityException e) {
+                    metadataBuilder.putString(key, null);
+                }
+            }
+            MediaMetadata sanitizedMetadata = metadataBuilder.build();
+            // sanitizedMetadata.size() guarantees that the underlying bundle is unparceled
+            // before we set it to prevent concurrent reads from throwing an
+            // exception
+            sanitizedMetadata.size();
+            return sanitizedMetadata;
+        }
+
         @Override
         public void setPlaybackState(PlaybackState state) throws RemoteException {
             int oldState = mPlaybackState == null