From 77ea683cb5ea5f23a8bfda728b609c971baf731e Mon Sep 17 00:00:00 2001
From: Makoto Onuki <omakoto@google.com>
Date: Mon, 13 Sep 2021 15:12:14 -0700
Subject: [PATCH] Fix inverse lock order in AppsFilter

Bug: 199332741
Test: manual test:
$ m ComponentAliasTests
$ adb install -r $OUT/testcases/ComponentAliasTests/arm64/ComponentAliasTests.apk
$ adb shell am compat disable FILTER_APPLICATION_QUERY android.content.componentalias.tests
$ adb install -r $OUT/testcases/ComponentAliasTests/arm64/ComponentAliasTests.apk

-> This shouldn't hang up the device

Change-Id: Ie9f903e312a4e7c3e64c2aac06d9e0cb1792eecf
---
 .../com/android/server/pm/AppsFilter.java     | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/services/core/java/com/android/server/pm/AppsFilter.java b/services/core/java/com/android/server/pm/AppsFilter.java
index 3818d74cfa0db..db0f1eb661710 100644
--- a/services/core/java/com/android/server/pm/AppsFilter.java
+++ b/services/core/java/com/android/server/pm/AppsFilter.java
@@ -300,6 +300,8 @@ public class AppsFilter implements Watchable, Snappable {
     /**
      * Provides system state to AppsFilter via {@link CurrentStateCallback} after properly guarding
      * the data with the package lock.
+     *
+     * Don't call {@link #runWithState} with {@link #mCacheLock} held.
      */
     @VisibleForTesting(visibility = PRIVATE)
     public interface StateProvider {
@@ -923,15 +925,16 @@ public class AppsFilter implements Watchable, Snappable {
     }
 
     private void updateShouldFilterCacheForPackage(String packageName) {
-        synchronized (mCacheLock) {
-            if (mShouldFilterCache != null) {
-                mStateProvider.runWithState((settings, users) -> {
-                    updateShouldFilterCacheForPackage(mShouldFilterCache, null /* skipPackage */,
-                            settings.get(packageName), settings, users,
-                            settings.size() /*maxIndex*/);
-                });
+        mStateProvider.runWithState((settings, users) -> {
+            synchronized (mCacheLock) {
+                if (mShouldFilterCache == null) {
+                    return;
+                }
+                updateShouldFilterCacheForPackage(mShouldFilterCache, null /* skipPackage */,
+                        settings.get(packageName), settings, users,
+                        settings.size() /*maxIndex*/);
             }
-        }
+        });
     }
 
     private void updateShouldFilterCacheForPackage(WatchedSparseBooleanMatrix cache,