From ba629da331d01d74067afdda5d4255682d4b24d7 Mon Sep 17 00:00:00 2001
From: Christopher Tate <ctate@google.com>
Date: Wed, 13 Nov 2013 17:42:28 -0800
Subject: [PATCH] Ensure recipient can be launched before attempting broadcast
 delivery

User removal or eviction inherently races with broadcast delivery.  This
patch introduces a latest-possible recheck of the availbility of the
target application before attempting to send it a broadcast.

Once the process has actually been spun up the system is essentially
committed to presenting it as a running application, and there is no
later check of the availability of the app: the failure mode for
continuing to attempt delivery is a crash *in the app process*,
and is user-visible.

We now check the app+userid existence of the intended recipient
just prior to committing to launch its process for receipt, and
if it is no longer available we simply skip that receiver and
continue normally.

Bug 11652784
Bug 11272019
Bug 8263020

Change-Id: Ib19ba2af493250890db7371c1a9f853772db1af0
---
 .../android/content/pm/IPackageManager.aidl   |  1 +
 .../android/content/pm/PackageParser.java     |  4 ++++
 .../com/android/server/am/BroadcastQueue.java | 21 +++++++++++++++++++
 .../server/pm/PackageManagerService.java      | 18 ++++++++++++++++
 4 files changed, 44 insertions(+)

diff --git a/core/java/android/content/pm/IPackageManager.aidl b/core/java/android/content/pm/IPackageManager.aidl
index 267fb2af2dd16..20002ad9d4714 100644
--- a/core/java/android/content/pm/IPackageManager.aidl
+++ b/core/java/android/content/pm/IPackageManager.aidl
@@ -53,6 +53,7 @@ import android.content.IntentSender;
  *  {@hide}
  */
 interface IPackageManager {
+    boolean isPackageAvailable(String packageName, int userId);
     PackageInfo getPackageInfo(String packageName, int flags, int userId);
     int getPackageUid(String packageName, int userId);
     int[] getPackageGids(String packageName);
diff --git a/core/java/android/content/pm/PackageParser.java b/core/java/android/content/pm/PackageParser.java
index 17d13e500e8e8..e6da288fedbdb 100644
--- a/core/java/android/content/pm/PackageParser.java
+++ b/core/java/android/content/pm/PackageParser.java
@@ -282,6 +282,10 @@ public class PackageParser {
                 || (flags & PackageManager.GET_UNINSTALLED_PACKAGES) != 0;
     }
 
+    public static boolean isAvailable(PackageUserState state) {
+        return checkUseInstalledOrBlocked(0, state);
+    }
+
     public static PackageInfo generatePackageInfo(PackageParser.Package p,
             int gids[], int flags, long firstInstallTime, long lastUpdateTime,
             HashSet<String> grantedPermissions, PackageUserState state, int userId) {
diff --git a/services/java/com/android/server/am/BroadcastQueue.java b/services/java/com/android/server/am/BroadcastQueue.java
index dd3d8aa5eca28..bfb667f8aca00 100644
--- a/services/java/com/android/server/am/BroadcastQueue.java
+++ b/services/java/com/android/server/am/BroadcastQueue.java
@@ -27,6 +27,7 @@ import android.content.ComponentName;
 import android.content.IIntentReceiver;
 import android.content.Intent;
 import android.content.pm.ActivityInfo;
+import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
 import android.content.pm.ResolveInfo;
 import android.os.Bundle;
@@ -814,6 +815,26 @@ public final class BroadcastQueue {
                         + " to " + r.curApp + ": process crashing");
                 skip = true;
             }
+            if (!skip) {
+                boolean isAvailable = false;
+                try {
+                    isAvailable = AppGlobals.getPackageManager().isPackageAvailable(
+                            info.activityInfo.packageName,
+                            UserHandle.getUserId(info.activityInfo.applicationInfo.uid));
+                } catch (Exception e) {
+                    // all such failures mean we skip this receiver
+                    Slog.w(TAG, "Exception getting recipient info for "
+                            + info.activityInfo.packageName, e);
+                }
+                if (!isAvailable) {
+                    if (DEBUG_BROADCAST) {
+                        Slog.v(TAG, "Skipping delivery to " + info.activityInfo.packageName
+                                + " / " + info.activityInfo.applicationInfo.uid
+                                + " : package no longer available");
+                    }
+                    skip = true;
+                }
+            }
 
             if (skip) {
                 if (DEBUG_BROADCAST)  Slog.v(TAG,
diff --git a/services/java/com/android/server/pm/PackageManagerService.java b/services/java/com/android/server/pm/PackageManagerService.java
index 7ae92513d6166..24f8ed804bc7a 100755
--- a/services/java/com/android/server/pm/PackageManagerService.java
+++ b/services/java/com/android/server/pm/PackageManagerService.java
@@ -1771,6 +1771,24 @@ public class PackageManagerService extends IPackageManager.Stub {
                 state, userId);
     }
 
+    public boolean isPackageAvailable(String packageName, int userId) {
+        if (!sUserManager.exists(userId)) return false;
+        enforceCrossUserPermission(Binder.getCallingUid(), userId, false, "is package available");
+        synchronized (mPackages) {
+            PackageParser.Package p = mPackages.get(packageName);
+            if (p != null) {
+                final PackageSetting ps = (PackageSetting) p.mExtras;
+                if (ps != null) {
+                    final PackageUserState state = ps.readUserState(userId);
+                    if (state != null) {
+                        return PackageParser.isAvailable(state);
+                    }
+                }
+            }
+        }
+        return false;
+    }
+
     @Override
     public PackageInfo getPackageInfo(String packageName, int flags, int userId) {
         if (!sUserManager.exists(userId)) return null;