From: Mykola Golub <mgolub@suse.com>
Date: Mon, 22 Feb 2021 16:22:54 +0000 (+0000)
Subject: rbd-mirror: reset update_status_task pointer in timer thread
X-Git-Tag: v17.1.0~2866^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=refs%2Fpull%2F39625%2Fhead;p=ceph.git

rbd-mirror: reset update_status_task pointer in timer thread

To avoid a time window when m_update_status_task is invalid. If
during this time the cancel_update_mirror_image_replay_status is
called, it may cancel some other's ImageReplayer task, if it
happened to add the task with the same address.

Fixes: https://tracker.ceph.com/issues/49418
Signed-off-by: Mykola Golub <mgolub@suse.com>
---

diff --git a/src/tools/rbd_mirror/ImageReplayer.cc b/src/tools/rbd_mirror/ImageReplayer.cc
index 9289510e11d9..f5cd65fe821e 100644
--- a/src/tools/rbd_mirror/ImageReplayer.cc
+++ b/src/tools/rbd_mirror/ImageReplayer.cc
@@ -690,18 +690,18 @@ template <typename I>
 void ImageReplayer<I>::handle_update_mirror_image_replay_status(int r) {
   dout(10) << dendl;
 
+  ceph_assert(ceph_mutex_is_locked_by_me(m_threads->timer_lock));
+
+  ceph_assert(m_update_status_task != nullptr);
+  m_update_status_task = nullptr;
+
   auto ctx = new LambdaContext([this](int) {
       update_mirror_image_status(false, boost::none);
 
-      {
-        std::unique_lock locker{m_lock};
-        std::unique_lock timer_locker{m_threads->timer_lock};
-        ceph_assert(m_update_status_task != nullptr);
-        m_update_status_task = nullptr;
-
-        schedule_update_mirror_image_replay_status();
-      }
+      std::unique_lock locker{m_lock};
+      std::unique_lock timer_locker{m_threads->timer_lock};
 
+      schedule_update_mirror_image_replay_status();
       m_in_flight_op_tracker.finish_op();
     });