diff --git a/flink-runtime/src/test/java/org/apache/flink/runtime/leaderelection/TestingListener.java b/flink-runtime/src/test/java/org/apache/flink/runtime/leaderelection/TestingListener.java
index 87decc7bddfd8b863c9f64e2d5f42eac2225d292..85715054d173f8b0f7891607cea157b7c85e41e0 100644
--- a/flink-runtime/src/test/java/org/apache/flink/runtime/leaderelection/TestingListener.java
+++ b/flink-runtime/src/test/java/org/apache/flink/runtime/leaderelection/TestingListener.java
@@ -51,11 +51,11 @@ public class TestingListener implements LeaderRetrievalListener {
 		long start = System.currentTimeMillis();
 		long curTimeout;
 
-		while (
+		synchronized (lock) {
+			while (
 				exception == null &&
-				(address == null || address.equals(oldAddress)) &&
-				(curTimeout = timeout - System.currentTimeMillis() + start) > 0) {
-			synchronized (lock) {
+					(address == null || address.equals(oldAddress)) &&
+					(curTimeout = timeout - System.currentTimeMillis() + start) > 0) {
 				try {
 					lock.wait(curTimeout);
 				} catch (InterruptedException e) {