From 32788b0555d2616d092740bde318145673b95b4d Mon Sep 17 00:00:00 2001
From: d34d <clark@cyngn.com>
Date: Tue, 8 Mar 2016 18:27:29 -0800
Subject: [PATCH] ExtViews: Guard against bad LLS providers

Add checks in onServiceConnected to make sure the provider was
created correctly and if not, log it and move on without imploding
the universe.

Change-Id: I6929a02631685636e2c52c2d6d13883f0c3a13c4
TICKET: CNYNGOS-2217
---
 .../externalviews/KeyguardExternalView.java   | 48 +++++++++++++------
 1 file changed, 33 insertions(+), 15 deletions(-)

diff --git a/src/java/cyanogenmod/externalviews/KeyguardExternalView.java b/src/java/cyanogenmod/externalviews/KeyguardExternalView.java
index f6ddfde..cf7b279 100644
--- a/src/java/cyanogenmod/externalviews/KeyguardExternalView.java
+++ b/src/java/cyanogenmod/externalviews/KeyguardExternalView.java
@@ -28,6 +28,7 @@ import android.os.Bundle;
 import android.os.IBinder;
 import android.os.RemoteException;
 import android.util.AttributeSet;
+import android.util.Log;
 import android.view.View;
 import android.view.ViewTreeObserver;
 import android.view.WindowManager;
@@ -43,6 +44,7 @@ import java.util.LinkedList;
  */
 public class KeyguardExternalView extends View implements ViewTreeObserver.OnPreDrawListener,
         IBinder.DeathRecipient {
+    private static final String TAG = KeyguardExternalView.class.getSimpleName();
 
     /**
      * An extra passed via an intent that provides a list of permissions that should be requested
@@ -107,29 +109,45 @@ public class KeyguardExternalView extends View implements ViewTreeObserver.OnPre
         @Override
         public void onServiceConnected(ComponentName name, IBinder service) {
             try {
-                mExternalViewProvider = IKeyguardExternalViewProvider.Stub.asInterface(
-                        IExternalViewProviderFactory.Stub.asInterface(service).
-                                createExternalView(null));
-                mExternalViewProvider.registerCallback(
-                        KeyguardExternalView.this.mKeyguardExternalViewCallbacks);
-                mService = service;
-                mService.linkToDeath(KeyguardExternalView.this, 0);
-                executeQueue();
+                IExternalViewProviderFactory factory = IExternalViewProviderFactory.Stub.asInterface(service);
+                if (factory != null) {
+                    mExternalViewProvider = IKeyguardExternalViewProvider.Stub.asInterface(
+                            factory.createExternalView(null));
+                    if (mExternalViewProvider != null) {
+                        mExternalViewProvider.registerCallback(
+                                KeyguardExternalView.this.mKeyguardExternalViewCallbacks);
+                        mService = service;
+                        mService.linkToDeath(KeyguardExternalView.this, 0);
+                        executeQueue();
+                    } else {
+                        Log.e(TAG, "Unable to get external view provider");
+                    }
+                } else {
+                    Log.e(TAG, "Unable to get external view provider factory");
+                }
             } catch (RemoteException e) {
                 e.printStackTrace();
             }
+            // We should unbind the service if we failed to connect to the provider
+            if (mService != service && service != null) {
+                mContext.unbindService(mServiceConnection);
+            }
         }
 
         @Override
         public void onServiceDisconnected(ComponentName name) {
-            try {
-                mExternalViewProvider.unregisterCallback(
-                        KeyguardExternalView.this.mKeyguardExternalViewCallbacks);
-            } catch (RemoteException e) {
+            if (mExternalViewProvider != null) {
+                try {
+                    mExternalViewProvider.unregisterCallback(
+                            KeyguardExternalView.this.mKeyguardExternalViewCallbacks);
+                } catch (RemoteException e) {
+                }
+                mExternalViewProvider = null;
+            }
+            if (mService != null) {
+                mService.unlinkToDeath(KeyguardExternalView.this, 0);
+                mService = null;
             }
-            mExternalViewProvider = null;
-            mService.unlinkToDeath(KeyguardExternalView.this, 0);
-            mService = null;
         }
     };