From c3565962b31eb58375181cc3ae2a12ad89917c6e Mon Sep 17 00:00:00 2001
From: Makoto Onuki <omakoto@google.com>
Date: Thu, 24 Feb 2022 15:19:42 -0800
Subject: [PATCH] Never instatiate App class multiple times

- GMS-core is still sometimes seeing the app class being
instatiated multiple times.

Let's just cache the app instance to avoid such situations.

- Also removed some tentative WTFs, which have never been triggered.
(so they should be unrelated to the dup-app bug)

Bug: 185177290
Test: Boot / treehugger
Change-Id: I4c74a5798264472d1bfbf5604f399a49e5946c64
---
 core/java/android/app/ActivityThread.java |  6 ----
 core/java/android/app/LoadedApk.java      | 34 +++++++++--------------
 2 files changed, 13 insertions(+), 27 deletions(-)

diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index 61d186579f1bd..64f0301fab22b 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -4469,12 +4469,6 @@ public final class ActivityThread extends ClientTransactionHandler
         // we are back active so skip it.
         unscheduleGcIdler();
 
-        // To investigate "duplciate Application objects" bug (b/185177290)
-        if (UserHandle.myUserId() != UserHandle.getUserId(data.info.applicationInfo.uid)) {
-            Slog.wtf(TAG, "handleCreateService called with wrong appinfo UID: myUserId="
-                    + UserHandle.myUserId() + " appinfo.uid=" + data.info.applicationInfo.uid);
-        }
-
         LoadedApk packageInfo = getPackageInfoNoCheck(
                 data.info.applicationInfo, data.compatInfo);
         Service service = null;
diff --git a/core/java/android/app/LoadedApk.java b/core/java/android/app/LoadedApk.java
index 99a523a0e18a1..cf259e577a5af 100644
--- a/core/java/android/app/LoadedApk.java
+++ b/core/java/android/app/LoadedApk.java
@@ -160,6 +160,13 @@ public final class LoadedApk {
     private final ArrayMap<Context, ArrayMap<ServiceConnection, LoadedApk.ServiceDispatcher>> mUnboundServices
         = new ArrayMap<>();
     private AppComponentFactory mAppComponentFactory;
+
+    /**
+     * We cache the instantiated application object for each package on this process here.
+     */
+    @GuardedBy("sApplications")
+    private static final ArrayMap<String, Application> sApplications = new ArrayMap<>(4);
+
     private final Object mLock = new Object();
 
     Application getApplication() {
@@ -1345,14 +1352,6 @@ public final class LoadedApk {
         return mResources;
     }
 
-    /**
-     * Used to investigate "duplicate app objects" bug (b/185177290).
-     * makeApplication() should only be called on the main thread, so no synchronization should
-     * be needed, but syncing anyway just in case.
-     */
-    @GuardedBy("sApplicationCache")
-    private static final ArrayMap<String, Application> sApplicationCache = new ArrayMap<>(4);
-
     @UnsupportedAppUsage
     public Application makeApplication(boolean forceDefaultAppClass,
             Instrumentation instrumentation) {
@@ -1361,15 +1360,8 @@ public final class LoadedApk {
         }
         Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "makeApplication");
 
-        // For b/185177290.
-        final boolean wrongUser =
-                UserHandle.myUserId() != UserHandle.getUserId(mApplicationInfo.uid);
-        if (wrongUser) {
-            Slog.wtf(TAG, "makeApplication called with wrong appinfo UID: myUserId="
-                    + UserHandle.myUserId() + " appinfo.uid=" + mApplicationInfo.uid);
-        }
-        synchronized (sApplicationCache) {
-            final Application cached = sApplicationCache.get(mPackageName);
+        synchronized (sApplications) {
+            final Application cached = sApplications.get(mPackageName);
             if (cached != null) {
                 // Looks like this is always happening for the system server, because
                 // the LoadedApk created in systemMain() -> attach() isn't cached properly?
@@ -1377,8 +1369,8 @@ public final class LoadedApk {
                     Slog.wtf(TAG, "App instance already created for package=" + mPackageName
                             + " instance=" + cached);
                 }
-                // TODO Return the cached one, unles it's for the wrong user?
-                // For now, we just add WTF checks.
+                mApplication = cached;
+                return cached;
             }
         }
 
@@ -1429,8 +1421,8 @@ public final class LoadedApk {
         }
         mActivityThread.mAllApplications.add(app);
         mApplication = app;
-        synchronized (sApplicationCache) {
-            sApplicationCache.put(mPackageName, app);
+        synchronized (sApplications) {
+            sApplications.put(mPackageName, app);
         }
 
         if (instrumentation != null) {