From 1379438362ac3b517b0b4949e893f1f7c69683e2 Mon Sep 17 00:00:00 2001
From: Lee Shombert <shombert@google.com>
Date: Wed, 4 Aug 2021 10:49:37 -0700
Subject: [PATCH] Correct locking in PackageManagerService

Bug: 194206793

PackageManagerService.mPackages was used as a lock exactly once.  This
meant there were two locks guarding LegacyPermissionState (and
possibly other state, as well): mLock and mPackages.  This change
replaces mPackages with mLock as the guard.

Two formatting errors were fixed.

An instrumented image was used to find other paths that might change
LegacyPermissionState outside of mLock; no such paths were found after
this fix.

Test: atest
 * android.car.apitest.CarUserManagerTest (requires cf_x86_auto-userdebug)
 * CtsContentTestCases:IntentFilterTest
 * CtsDynamicMimeHostTestCases
 * CtsRoleTestCases
 * FrameworksServicesTests:UserSystemPackageInstallerTest
 * FrameworksServicesTests:PackageManagerSettingsTests
 * FrameworksServicesTests:PackageManagerServiceTest
 * FrameworksServicesTests:AppsFilterTest
 * FrameworksServicesTests:PackageInstallerSessionTest
 * FrameworksServicesTests:ScanTests
 * UserLifecycleTests#startUser
 * UserLifecycleTests#stopUser
 * UserLifecycleTests#switchUser
 * FrameworksServicesTests:WatcherTest
 * android.appsecurity.cts.EphemeralTest
 * android.appsecurity.cts.InstantAppUserTest
Change-Id: If2914258c0a020fac124142cb292bafcee5e8a2a
---
 .../java/com/android/server/pm/PackageManagerService.java   | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/services/core/java/com/android/server/pm/PackageManagerService.java b/services/core/java/com/android/server/pm/PackageManagerService.java
index ee44c10edbf38..7d055ff43f370 100644
--- a/services/core/java/com/android/server/pm/PackageManagerService.java
+++ b/services/core/java/com/android/server/pm/PackageManagerService.java
@@ -26533,7 +26533,7 @@ public class PackageManagerService extends IPackageManager.Stub
     }
 
     boolean readPermissionStateForUser(@UserIdInt int userId) {
-        synchronized (mPackages) {
+        synchronized (mLock) {
             mPermissionManager.writeLegacyPermissionStateTEMP();
             mSettings.readPermissionStateForUserSyncLPr(userId);
             mPermissionManager.readLegacyPermissionStateTEMP();
@@ -26609,7 +26609,7 @@ public class PackageManagerService extends IPackageManager.Stub
         if (packageName == null || alias == null) {
             return null;
         }
-        synchronized(mLock) {
+        synchronized (mLock) {
             final AndroidPackage pkg = mPackages.get(packageName);
             if (pkg == null
                     || shouldFilterApplicationLocked(getPackageSetting(pkg.getPackageName()),
@@ -26656,7 +26656,7 @@ public class PackageManagerService extends IPackageManager.Stub
         if (packageName == null || ks == null) {
             return false;
         }
-        synchronized(mLock) {
+        synchronized (mLock) {
             final AndroidPackage pkg = mPackages.get(packageName);
             if (pkg == null
                     || shouldFilterApplicationLocked(getPackageSetting(pkg.getPackageName()),