From fbc7717851f2681d15fedd684ab530d7a4fc842e Mon Sep 17 00:00:00 2001
From: Alex Chau <alexchau@google.com>
Date: Thu, 18 Jan 2018 18:43:35 +0000
Subject: [PATCH] Add back missing synchronized in
 stopGuestOrEphemeralUserIfBackground

- mStartedUsers and mCurrentUserId should be locked by mLock

Bug: 72133858
Test: Manually create secondary user, and exit the user in SetupWizard
Change-Id: If59749c06c5d8174462a6f2a255517c60321d9f4
---
 .../java/com/android/server/am/UserController.java   | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/services/core/java/com/android/server/am/UserController.java b/services/core/java/com/android/server/am/UserController.java
index 65bebc6c235af..1a47aa5cd7773 100644
--- a/services/core/java/com/android/server/am/UserController.java
+++ b/services/core/java/com/android/server/am/UserController.java
@@ -795,11 +795,13 @@ class UserController implements Handler.Callback {
      */
     private void stopGuestOrEphemeralUserIfBackground(int oldUserId) {
         if (DEBUG_MU) Slog.i(TAG, "Stop guest or ephemeral user if background: " + oldUserId);
-        UserState oldUss = mStartedUsers.get(oldUserId);
-        if (oldUserId == UserHandle.USER_SYSTEM || oldUserId == mCurrentUserId || oldUss == null
-                || oldUss.state == UserState.STATE_STOPPING
-                || oldUss.state == UserState.STATE_SHUTDOWN) {
-            return;
+        synchronized(mLock) {
+            UserState oldUss = mStartedUsers.get(oldUserId);
+            if (oldUserId == UserHandle.USER_SYSTEM || oldUserId == mCurrentUserId || oldUss == null
+                    || oldUss.state == UserState.STATE_STOPPING
+                    || oldUss.state == UserState.STATE_SHUTDOWN) {
+                return;
+            }
         }
 
         UserInfo userInfo = getUserInfo(oldUserId);