Gerrit

Project: gerrit
Branch: stable-3.6

commit 5778c02f688d52d12d8603421cd08b1a84b0d199
Author: Marcin Czech <maczech@gmail.com>
Date:   Mon Aug 07 16:52:26 2023

    Avoid NullPointerException when deleting multiple tags
   
    To avoid NPE make sure that ref is not read again after checking if
    ref exists. This prevent the issue when other call already removed
    the tag and we try to read it. Proper behaviour is to try to delete it
    and return `Cannot delete refs/tags/...: LOCK_FAILURE` if tag is already
    deleted.
   
    Bug: Issue 291102119
    Release-Notes: Avoid NullPointerException when deleting multiple tags
    Change-Id: I8e19d756db2ecf15e6e5e61ec0346a7cfc6a85e3

M       java/com/google/gerrit/server/restapi/project/DeleteRef.java

https://gerrit-review.googlesource.com/382076

There is still a case that is uncovered by this fix and it has to do with a single tag deletion.

In the case of a single ref, `deleteMultipleRefs` falls back to `deleteSingleRef()`, which also suffers from the same race condition, causing the following NPE:

2023-09-21T14:58:32.107Z java.lang.NullPointerException
        at com.google.gerrit.server.restapi.project.DeleteRef.deleteSingleRef(DeleteRef.java:119)
        at com.google.gerrit.server.restapi.project.DeleteRef.deleteMultipleRefs(DeleteRef.java:174)
        at com.google.gerrit.server.restapi.project.DeleteTags.apply(DeleteTags.java:50)
        at com.google.gerrit.server.restapi.project.DeleteTags.apply(DeleteTags.java:31)
        at com.google.gerrit.httpd.restapi.RestApiServlet.lambda$invokeRestModifyViewWithRetry$7(RestApiServlet.java:924)
        at com.github.rholder.retry.AttemptTimeLimiters$NoAttemptTimeLimit.call(AttemptTimeLimiters.java:78)
        at com.github.rholder.retry.Retryer.call(Retryer.java:160)
        at com.google.gerrit.server.update.RetryHelper.executeWithTimeoutCount(RetryHelper.java:564)
        at com.google.gerrit.server.update.RetryHelper.execute(RetryHelper.java:507)
        at com.google.gerrit.server.update.RetryableAction.call(RetryableAction.java:173)
        at com.google.gerrit.httpd.restapi.RestApiServlet.invokeRestEndpointWithRetry(RestApiServlet.java:999)
        at com.google.gerrit.httpd.restapi.RestApiServlet.invokeRestModifyViewWithRetry(RestApiServlet.java:919)
        at com.google.gerrit.httpd.restapi.RestApiServlet.service(RestApiServlet.java:565)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)

Project: gerrit
Branch: stable-3.6

commit 29b4af9ee55ae16064b38db9c86255ac037d27e9
Author: Antonio Barone <syntonyze@gmail.com>
Date:   Thu Sep 21 20:14:46 2023

    Avoid NPE when deleting single ref
   
    Change I8e19d756db fixed a bug where an NPE was thrown during the
    deletion of multiple refs if one of them didn't exist, or possibly
    already removed by a concurrent caller.
   
    The `deleteMultipleRefs()` method however, falls back to calling the
    `deleteSingleRef()` method, which also suffers from the same issue.
   
    Fix the `deleteSingleRef()` method to account for unexisting refs, so
    that a concurrent execution from another caller does not cause an NPE.
   
    Release-Notes: Avoid NullPointerException when deleting a single ref
    Bug: Issue 291102119
    Change-Id: Ibe79290f4eb7332cc22e72c906fe5f60bedbcca6

M       java/com/google/gerrit/server/restapi/project/DeleteRef.java

https://gerrit-review.googlesource.com/387103