From a5e7d3cdf9bbc597a3cde4f029701a4532367ade Mon Sep 17 00:00:00 2001
From: Grace Jia <xiaotonj@google.com>
Date: Thu, 15 Jul 2021 11:36:49 -0700
Subject: [PATCH] Add a lock for call add/remove operations to avoid
 ConcurrentModificationException.

Bug: 189816293
Test: InCallService cts tests
Change-Id: I123b2de55b856d12ee2a5e6d2fa49c15a74592fc
---
 telecomm/java/android/telecom/Phone.java | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/telecomm/java/android/telecom/Phone.java b/telecomm/java/android/telecom/Phone.java
index a427ed612b31b..02bd0010de99e 100644
--- a/telecomm/java/android/telecom/Phone.java
+++ b/telecomm/java/android/telecom/Phone.java
@@ -139,6 +139,8 @@ public final class Phone {
      */
     private final int mTargetSdkVersion;
 
+    private final Object mLock = new Object();
+
     Phone(InCallAdapter adapter, String callingPackage, int targetSdkVersion) {
         mInCallAdapter = adapter;
         mCallingPackage = callingPackage;
@@ -156,8 +158,12 @@ public final class Phone {
         if (call == null) {
             call = new Call(this, parcelableCall.getId(), mInCallAdapter,
                     parcelableCall.getState(), mCallingPackage, mTargetSdkVersion);
-            mCallByTelecomCallId.put(parcelableCall.getId(), call);
-            mCalls.add(call);
+
+            synchronized (mLock) {
+                mCallByTelecomCallId.put(parcelableCall.getId(), call);
+                mCalls.add(call);
+            }
+
             checkCallTree(parcelableCall);
             call.internalUpdate(parcelableCall, mCallByTelecomCallId);
             fireCallAdded(call);
@@ -169,8 +175,10 @@ public final class Phone {
     }
 
     final void internalRemoveCall(Call call) {
-        mCallByTelecomCallId.remove(call.internalGetCallId());
-        mCalls.remove(call);
+        synchronized (mLock) {
+            mCallByTelecomCallId.remove(call.internalGetCallId());
+            mCalls.remove(call);
+        }
 
         InCallService.VideoCall videoCall = call.getVideoCall();
         if (videoCall != null) {