From: "Yan, Zheng" <zyan@redhat.com>
Date: Mon, 11 Feb 2019 15:18:52 +0800
Subject: ceph: avoid repeatedly adding inode to mdsc->snap_flush_list
Git-commit: 04242ff3ac0abbaa4362f97781dac268e6c3541a
Patch-mainline: v5.0-rc8
References: bsc#1126790 bsc#1126775
Otherwise, mdsc->snap_flush_list may get corrupted.
Cc: stable@vger.kernel.org
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
fs/ceph/snap.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -615,7 +615,8 @@ int __ceph_finish_cap_snap(struct ceph_i
capsnap->size);
spin_lock(&mdsc->snap_flush_lock);
- list_add_tail(&ci->i_snap_flush_item, &mdsc->snap_flush_list);
+ if (list_empty(&ci->i_snap_flush_item))
+ list_add_tail(&ci->i_snap_flush_item, &mdsc->snap_flush_list);
spin_unlock(&mdsc->snap_flush_lock);
return 1; /* caller may want to ceph_flush_snaps */
}