4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yan, Zheng <zyan@xxxxxxxxxx> commit 04242ff3ac0abbaa4362f97781dac268e6c3541a upstream. Otherwise, mdsc->snap_flush_list may get corrupted. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: "Yan, Zheng" <zyan@xxxxxxxxxx> Reviewed-by: Ilya Dryomov <idryomov@xxxxxxxxx> Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ceph/snap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/ceph/snap.c +++ b/fs/ceph/snap.c @@ -611,7 +611,8 @@ 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 */ }
