[PATCH 4.14 39/62] ceph: dont try fill file_lock on unsuccessful GETFILELOCK reply

From: Greg Kroah-Hartman
Date: Tue Aug 27 2019 - 03:53:21 EST


From: Jeff Layton <jlayton@xxxxxxxxxx>

commit 28a282616f56990547b9dcd5c6fbd2001344664c upstream.

When ceph_mdsc_do_request returns an error, we can't assume that the
filelock_reply pointer will be set. Only try to fetch fields out of
the r_reply_info when it returns success.

Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Hector Martin <hector@xxxxxxxxxxxxxx>
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Reviewed-by: "Yan, Zheng" <zyan@xxxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/ceph/locks.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/fs/ceph/locks.c
+++ b/fs/ceph/locks.c
@@ -78,8 +78,7 @@ static int ceph_lock_message(u8 lock_typ
req->r_wait_for_completion = ceph_lock_wait_for_completion;

err = ceph_mdsc_do_request(mdsc, inode, req);
-
- if (operation == CEPH_MDS_OP_GETFILELOCK) {
+ if (!err && operation == CEPH_MDS_OP_GETFILELOCK) {
fl->fl_pid = -le64_to_cpu(req->r_reply_info.filelock_reply->pid);
if (CEPH_LOCK_SHARED == req->r_reply_info.filelock_reply->type)
fl->fl_type = F_RDLCK;