[jira] [Commented] (GEODE-4072) Race condition in AckReaderThread.shutdown

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/GEODE-4072?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16284458#comment-16284458 ] 

ASF GitHub Bot commented on GEODE-4072:
---------------------------------------

nabarunnag opened a new pull request #1148: GEODE-4072: Fixed race condition in AckThreadReader shutdown.
URL: https://github.com/apache/geode/pull/1148
 
 
   	* The global connection variable may be set to null by another thread.
   	* Assign the local variable to the connection variable and then perform all the null checks on that local variable.
   
   Thank you for submitting a contribution to Apache Geode.
   
   In order to streamline the review of the contribution we ask you
   to ensure the following steps have been taken:
   
   ### For all changes:
   - [ ] Is there a JIRA ticket associated with this PR? Is it referenced in the commit message?
   
   - [ ] Has your PR been rebased against the latest commit within the target branch (typically `develop`)?
   
   - [ ] Is your initial contribution a single, squashed commit?
   
   - [ ] Does `gradlew build` run cleanly?
   
   - [ ] Have you written or updated unit tests to verify your changes?
   
   - [ ] If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under [ASF 2.0](http://www.apache.org/legal/resolved.html#category-a)?
   
   ### Note:
   Please ensure that once the PR is submitted, you check travis-ci for build issues and
   submit an update to your PR as soon as possible. If you need help, please send an
   email to dev@geode.apache.org.
   

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


> Race condition in AckReaderThread.shutdown 
> -------------------------------------------
>
>                 Key: GEODE-4072
>                 URL: https://issues.apache.org/jira/browse/GEODE-4072
>             Project: Geode
>          Issue Type: Bug
>          Components: wan
>            Reporter: nabarun
>            Assignee: nabarun
>
> *+Issue+*
> {code:title=AckReaderThread.java}
> if (connection != null) {
>         Connection conn = connection;
>         shutDownAckReaderConnection();
>         if (!conn.isDestroyed()) {
>           conn.destroy();
>           sender.getProxy().returnConnection(conn);
>         }
>       }
> {code}
> The global connection variable may be set to null before it is assigned to the local variable, resulting in NPE.
> *Solution*:
> --set the local variable to the connection variable and use that local variable for null checks.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)