From 6c4844062763fa4c1be5638f5a54c3d935281878 Mon Sep 17 00:00:00 2001
From: Jason Lowe <jlowe@yahoo-inc.com>
Date: Fri, 3 Mar 2017 08:23:08 -0600
Subject: [PATCH] YARN-6263. NMTokenSecretManagerInRM.createAndGetNMToken is
 not thread safe. Contributed by Haibo Chen

(cherry picked from commit e58fc7603053e3ac1bc2464f9622995017db5245)
---
 .../resourcemanager/security/NMTokenSecretManagerInRM.java    | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/security/NMTokenSecretManagerInRM.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/security/NMTokenSecretManagerInRM.java
index 1471f780b56..956391edeea 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/security/NMTokenSecretManagerInRM.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/security/NMTokenSecretManagerInRM.java
@@ -192,7 +192,7 @@ public class NMTokenSecretManagerInRM extends BaseNMTokenSecretManager {
   public NMToken createAndGetNMToken(String applicationSubmitter,
       ApplicationAttemptId appAttemptId, Container container) {
     try {
-      this.readLock.lock();
+      this.writeLock.lock();
       HashSet<NodeId> nodeSet = this.appAttemptToNodeKeyMap.get(appAttemptId);
       NMToken nmToken = null;
       if (nodeSet != null) {
@@ -208,7 +208,7 @@ public class NMTokenSecretManagerInRM extends BaseNMTokenSecretManager {
       }
       return nmToken;
     } finally {
-      this.readLock.unlock();
+      this.writeLock.unlock();
     }
   }