From 0a05f5475f1f9ea0e61bb69b9c98f4b8ef850b20 Mon Sep 17 00:00:00 2001
From: Jing Ji <jji@google.com>
Date: Wed, 28 Jul 2021 10:40:21 -0700
Subject: [PATCH] Fix NullPointerException in PhantomProcessList due to race
 condition

Bug: 194897294
Bug: 194146206
Test: atest AppChildProcessTest
Test: atest CtsAppTestCases:ActivityManagerTest
Change-Id: I5d395726d2ff404e8e82d21a7886511a06288c43
---
 .../core/java/com/android/server/am/PhantomProcessList.java    | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/services/core/java/com/android/server/am/PhantomProcessList.java b/services/core/java/com/android/server/am/PhantomProcessList.java
index ca31681616051..b07684c9a0043 100644
--- a/services/core/java/com/android/server/am/PhantomProcessList.java
+++ b/services/core/java/com/android/server/am/PhantomProcessList.java
@@ -365,6 +365,9 @@ public final class PhantomProcessList {
     private int onPhantomProcessFdEvent(FileDescriptor fd, int events) {
         synchronized (mLock) {
             final PhantomProcessRecord proc = mPhantomProcessesPidFds.get(fd.getInt$());
+            if (proc == null) {
+                return 0;
+            }
             if ((events & EVENT_INPUT) != 0) {
                 proc.onProcDied(true);
             } else {