From: Abhishek Lekshmanan <abhishek.lekshmanan@cern.ch>
Date: Tue, 1 Apr 2025 10:04:09 +0000 (+0200)
Subject: mds: MDCache request cleanup handles potential null mdr
X-Git-Tag: testing/wip-jcollin-testing-20251203.125108-squid~4^2~1
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=02cc17d76c9099603e3331b216807c032a3ad821;p=ceph-ci.git

mds: MDCache request cleanup handles potential null mdr

In cases where there is a single element in a batch_op_map,new_batch_head
is a nullptr, when this is retried at Finisher we'd hit one of the asserts when
dereferencing

Fixes: https://tracker.ceph.com/issues/70769
Signed-off-by: Abhishek Lekshmanan <abhishek.lekshmanan@cern.ch>
(cherry picked from commit e63f8cc54d03dbdd147cdd2c301adef119a640da)
---

diff --git a/src/mds/MDCache.cc b/src/mds/MDCache.cc
index 66071d385db..d3c8e8a4927 100644
--- a/src/mds/MDCache.cc
+++ b/src/mds/MDCache.cc
@@ -9916,8 +9916,9 @@ void MDCache::request_cleanup(const MDRequestRef& mdr)
     auto new_batch_head = it->second->find_new_head();
     if (!new_batch_head) {
       mdr->batch_op_map->erase(it);
+    } else {
+      mds->finisher->queue(new C_MDS_RetryRequest(this, new_batch_head));
     }
-    mds->finisher->queue(new C_MDS_RetryRequest(this, new_batch_head));
   }
 
   if (mdr->has_more()) {