[ Upstream commit fa99677342 ]
Make sure the delayed work stopped before releasing the resources.
cancel_delayed_work_sync() will only guarantee that the work finishes
executing if the work is already in the ->worklist. That means after
the cancel_delayed_work_sync() returns, it will leave the work requeued
if it was rearmed at the end. That can lead to a use after free once the
work struct is freed.
Fix it by flushing the delayed work instead of trying to cancel it, and
ensure that the work doesn't rearm if the mdsc is stopping.
URL: https://tracker.ceph.com/issues/46293
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
d033576669