commit ac116df5181b6bf82b501c2141f65633a935d9f0
author Michal Karpinski <mkarpinski@google.com> Mon Dec 10 17:51:42 2018 +0000
committer Michal Karpinski <mkarpinski@google.com> Thu Jan 03 12:26:43 2019 +0000
tree 1284a922cb217b9dfa325457e8828d68eda9e58e
parent 67b5e2ae1af0a3ce036d9cb8288e683a6ff86ccb

Block activity starts from background when realCallingUid is
a persistent system process and the start wasn't explicitly
whitelisted by the sender

Also, adds mechanism to temporary whitelist processes when
broadcast-based PendingIntent was whitelisted, so that
activities can be opened for the duration of the broadcast
being processed.

For now, all this is only wired for notifications.

Note: those whitelists are separate - only UI elements like
notifications will leverage both in order to support trampolines.
Other system-based PendingIntent senders should only use the
activity-based whitelist when they want an activity to be opened
from background.

Bug: 110956953
Test: atest WmTests:ActivityStarterTests
Test: manual with Play notifications that are known
      for doing trampolines

Change-Id: Ibab91cdbe7afc0aed29d430dd41327272020925b

services/core/java/com/android/server/wm/ActivityTaskManagerService.java

diff --git a/services/core/java/com/android/server/wm/ActivityTaskManagerService.java b/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
index c4be1ba537..a669ace 100644
--- a/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
+++ b/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
@@ -960,7 +960,7 @@
         // TODO: Switch to user app stacks here.
         return getActivityStartController().startActivities(caller, -1, callingPackage, intents,
                 resolvedTypes, resultTo, SafeActivityOptions.fromBundle(bOptions), userId, reason,
-                null /* originatingPendingIntent */);
+                null /* originatingPendingIntent */, false /* allowBackgroundActivityStart */);
     }
 
     @Override
@@ -5787,18 +5787,20 @@
                         packageUid, packageName,
                         intents, resolvedTypes, null /* resultTo */,
                         SafeActivityOptions.fromBundle(bOptions), userId,
-                        false /* validateIncomingUser */, null /* originatingPendingIntent */);
+                        false /* validateIncomingUser */, null /* originatingPendingIntent */,
+                        false /* allowBackgroundActivityStart */);
             }
         }
 
         @Override
         public int startActivitiesInPackage(int uid, String callingPackage, Intent[] intents,
                 String[] resolvedTypes, IBinder resultTo, SafeActivityOptions options, int userId,
-                boolean validateIncomingUser, PendingIntentRecord originatingPendingIntent) {
+                boolean validateIncomingUser, PendingIntentRecord originatingPendingIntent,
+                boolean allowBackgroundActivityStart) {
             synchronized (mGlobalLock) {
                 return getActivityStartController().startActivitiesInPackage(uid, callingPackage,
                         intents, resolvedTypes, resultTo, options, userId, validateIncomingUser,
-                        originatingPendingIntent);
+                        originatingPendingIntent, allowBackgroundActivityStart);
             }
         }
 
@@ -5807,12 +5809,14 @@
                 String callingPackage, Intent intent, String resolvedType, IBinder resultTo,
                 String resultWho, int requestCode, int startFlags, SafeActivityOptions options,
                 int userId, TaskRecord inTask, String reason, boolean validateIncomingUser,
-                PendingIntentRecord originatingPendingIntent) {
+                PendingIntentRecord originatingPendingIntent,
+                boolean allowBackgroundActivityStart) {
             synchronized (mGlobalLock) {
                 return getActivityStartController().startActivityInPackage(uid, realCallingPid,
                         realCallingUid, callingPackage, intent, resolvedType, resultTo, resultWho,
                         requestCode, startFlags, options, userId, inTask, reason,
-                        validateIncomingUser, originatingPendingIntent);
+                        validateIncomingUser, originatingPendingIntent,
+                        allowBackgroundActivityStart);
             }
         }