ceph: fix mdsmap decode when there are MDS's beyond max_mds

If the max_mds is decreased in a cephfs cluster, there is a window
of time before the MDSs are removed. If a map goes out during this
period, the mdsmap may show the decreased max_mds but still shows
those MDSes as in or in the export target list.

Ensure that we don't fail the map decode in that case.

Cc: stable@vger.kernel.org
URL: https://tracker.ceph.com/issues/52436
Fixes: d517b3983d ("ceph: reconnect to the export targets on new mdsmaps")
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This commit is contained in:
Xiubo Li 2021-11-05 17:34:18 +08:00 committed by Ilya Dryomov
parent e90334e89b
commit 0e24421ac4

View File

@ -263,10 +263,6 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end, bool msgr2)
goto nomem;
for (j = 0; j < num_export_targets; j++) {
target = ceph_decode_32(&pexport_targets);
if (target >= m->possible_max_rank) {
err = -EIO;
goto corrupt;
}
info->export_targets[j] = target;
}
} else {