Protect against mConfigs changes in writeXml

Test: manual
Fixes: 131585941
Change-Id: I0241d876910a6a7008e00e27b846248363978903

1 files changed, 7 insertions, 6 deletions

diff --git a/services/core/java/com/android/server/notification/ZenModeHelper.java b/services/core/java/com/android/server/notification/ZenModeHelper.java
index 981e0f58ef2b..f81015dae468 100644
--- a/services/core/java/com/android/server/notification/ZenModeHelper.java
+++ b/services/core/java/com/android/server/notification/ZenModeHelper.java
@@ -80,7 +80,6 @@ import org.xmlpull.v1.XmlSerializer;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;
 
@@ -731,12 +730,14 @@ public class ZenModeHelper {
 
     public void writeXml(XmlSerializer out, boolean forBackup, Integer version, int userId)
             throws IOException {
-        final int N = mConfigs.size();
-        for (int i = 0; i < N; i++) {
-            if (forBackup && mConfigs.keyAt(i) != userId) {
-                continue;
+        synchronized (mConfigs) {
+            final int n = mConfigs.size();
+            for (int i = 0; i < n; i++) {
+                if (forBackup && mConfigs.keyAt(i) != userId) {
+                    continue;
+                }
+                mConfigs.valueAt(i).writeXml(out, version);
             }
-            mConfigs.valueAt(i).writeXml(out, version);
         }
     }