From 24d405b1b0dd96317edec600fc2ca894b6954e20 Mon Sep 17 00:00:00 2001
From: markt <markt@13f79535-47bb-0310-9956-ffa450edef68>
Date: Thu, 9 Jun 2011 19:15:40 +0000
Subject: [PATCH] Prevent possible NPE when processing WebDAV locks.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1134048 13f79535-47bb-0310-9956-ffa450edef68
---
 java/org/apache/catalina/servlets/WebdavServlet.java | 16 +++++++++-------
 webapps/docs/changelog.xml                           |  3 +++
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/java/org/apache/catalina/servlets/WebdavServlet.java b/java/org/apache/catalina/servlets/WebdavServlet.java
index a35d4c0d3..d08dbd020 100644
--- a/java/org/apache/catalina/servlets/WebdavServlet.java
+++ b/java/org/apache/catalina/servlets/WebdavServlet.java
@@ -1337,13 +1337,15 @@ public class WebdavServlet
             LockInfo toRenew = resourceLocks.get(path);
             Enumeration<String> tokenList = null;
 
-            // At least one of the tokens of the locks must have been given
-            tokenList = toRenew.tokens.elements();
-            while (tokenList.hasMoreElements()) {
-                String token = tokenList.nextElement();
-                if (ifHeader.indexOf(token) != -1) {
-                    toRenew.expiresAt = lock.expiresAt;
-                    lock = toRenew;
+            if (toRenew != null) {
+                // At least one of the tokens of the locks must have been given
+                tokenList = toRenew.tokens.elements();
+                while (tokenList.hasMoreElements()) {
+                    String token = tokenList.nextElement();
+                    if (ifHeader.indexOf(token) != -1) {
+                        toRenew.expiresAt = lock.expiresAt;
+                        lock = toRenew;
+                    }
                 }
             }
 
diff --git a/webapps/docs/changelog.xml b/webapps/docs/changelog.xml
index ecc8b17ca..9545dcecf 100644
--- a/webapps/docs/changelog.xml
+++ b/webapps/docs/changelog.xml
@@ -85,6 +85,9 @@
         <bug>51344</bug>: Fix problem with Lifecycle re-factoring for deprecated
         embedded class that prevented events being triggered. (markt) 
       </fix>
+      <fix>
+        Prevent possible NPE when processing WebDAV locks. (markt)
+      </fix>
     </changelog>
   </subsection>
   <subsection name="Coyote">
-- 
2.11.0