From 07b1300e12b5f019735d2e6678f8801d6b57ac46 Mon Sep 17 00:00:00 2001
From: Louis Chang <louischang@google.com>
Date: Wed, 27 Nov 2019 22:08:37 +0800
Subject: [PATCH] Avoid recycle task of different user

A task that belongs to work profile user was reused while starting
an owner user activity. The task was recycled and had delivered
new intent to the existing top activity (belongs to work profile user)
instead of adding a new activity (of owner profile user) on top.

Bug: 144915832
Test: atest ActivityStarterTests
Test: repro steps on bug
Change-Id: Ic210f8c436c086bca590facbdba5fe5fa556f4df
---
 .../com/android/server/wm/ActivityStarter.java  | 17 ++++++++++++++---
 .../android/server/wm/ActivityStarterTests.java | 15 +++++++++++++++
 2 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/services/core/java/com/android/server/wm/ActivityStarter.java b/services/core/java/com/android/server/wm/ActivityStarter.java
index 0f912f1a49562..7960842daf50b 100644
--- a/services/core/java/com/android/server/wm/ActivityStarter.java
+++ b/services/core/java/com/android/server/wm/ActivityStarter.java
@@ -149,7 +149,8 @@ class ActivityStarter {
     private final ActivityStartController mController;
 
     // Share state variable among methods when starting an activity.
-    private ActivityRecord mStartActivity;
+    @VisibleForTesting
+    ActivityRecord mStartActivity;
     private Intent mIntent;
     private int mCallingUid;
     private ActivityOptions mOptions;
@@ -173,7 +174,8 @@ class ActivityStarter {
     private int mPreferredDisplayId;
 
     private Task mInTask;
-    private boolean mAddingToTask;
+    @VisibleForTesting
+    boolean mAddingToTask;
     private Task mReuseTask;
 
     private ActivityInfo mNewTaskInfo;
@@ -1665,7 +1667,16 @@ class ActivityStarter {
      * - Comply to the specified activity launch flags
      * - Determine whether need to add a new activity on top or just brought the task to front.
      */
-    private int recycleTask(Task targetTask, ActivityRecord targetTaskTop, Task reusedTask) {
+    @VisibleForTesting
+    int recycleTask(Task targetTask, ActivityRecord targetTaskTop, Task reusedTask) {
+        // Should not recycle task which is from a different user, just adding the starting
+        // activity to the task.
+        if (targetTask.mUserId != mStartActivity.mUserId) {
+            mTargetStack = targetTask.getStack();
+            mAddingToTask = true;
+            return START_SUCCESS;
+        }
+
         // True if we are clearing top and resetting of a standard (default) launch mode
         // ({@code LAUNCH_MULTIPLE}) activity. The existing activity will be finished.
         final boolean clearTopAndResetStandardLaunchMode =
diff --git a/services/tests/wmtests/src/com/android/server/wm/ActivityStarterTests.java b/services/tests/wmtests/src/com/android/server/wm/ActivityStarterTests.java
index ae1bb8e57e56e..c712d6dedb27c 100644
--- a/services/tests/wmtests/src/com/android/server/wm/ActivityStarterTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/ActivityStarterTests.java
@@ -962,4 +962,19 @@ public class ActivityStarterTests extends ActivityTestsBase {
         }
         assertThat(exceptionCaught).isTrue();
     }
+
+    @Test
+    public void testRecycleTaskFromAnotherUser() {
+        final ActivityStarter starter = prepareStarter(0 /* flags */);
+        starter.mStartActivity = new ActivityBuilder(mService).build();
+        final Task task = new TaskBuilder(mService.mStackSupervisor)
+                .setStack(mService.mRootActivityContainer.getDefaultDisplay().createStack(
+                        WINDOWING_MODE_FULLSCREEN, ACTIVITY_TYPE_STANDARD, true /* onTop */))
+                .setUserId(10)
+                .build();
+
+        final int result = starter.recycleTask(task, null, null);
+        assertThat(result == START_SUCCESS).isTrue();
+        assertThat(starter.mAddingToTask).isTrue();
+    }
 }