From: "Yan, Zheng" <zyan@redhat.com>
Date: Fri, 22 Sep 2017 09:26:57 +0800
Subject: ceph: properly queue cap snap for newly created snap realm
Git-commit: 9f4057fc937f200f000dbc378c5c3e37d45e31dc
Patch-mainline: v4.14-rc4
References: FATE#324714
commit 3ae0bebc "ceph: queue cap snap only when snap realm's
context changes" introduced a regression: we may not call
queue_realm_cap_snaps() for newly created snap realm. This
regression allows unflushed snapshot data to be overwritten.
Link: http://tracker.ceph.com/issues/21483
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
fs/ceph/snap.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index 1ffc8b426c1c..7fc0b850c352 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -374,12 +374,10 @@ static int build_snap_context(struct ceph_snap_realm *realm,
realm->ino, realm, snapc, snapc->seq,
(unsigned int) snapc->num_snaps);
- if (realm->cached_context) {
- ceph_put_snap_context(realm->cached_context);
- /* queue realm for cap_snap creation */
- list_add_tail(&realm->dirty_item, dirty_realms);
- }
+ ceph_put_snap_context(realm->cached_context);
realm->cached_context = snapc;
+ /* queue realm for cap_snap creation */
+ list_add_tail(&realm->dirty_item, dirty_realms);
return 0;
fail: