[PATCH 4.14 025/105] ceph: add missing check in d_revalidate snapdir handling

From: Greg Kroah-Hartman
Date: Mon Nov 11 2019 - 13:36:01 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

commit 1f08529c84cfecaf1261ed9b7e17fab18541c58f upstream.

We should not play with dcache without parent locked...

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/ceph/inode.c | 1 +
1 file changed, 1 insertion(+)

--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1347,6 +1347,7 @@ retry_lookup:
dout(" final dn %p\n", dn);
} else if ((req->r_op == CEPH_MDS_OP_LOOKUPSNAP ||
req->r_op == CEPH_MDS_OP_MKSNAP) &&
+ test_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags) &&
!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) {
struct dentry *dn = req->r_dentry;
struct inode *dir = req->r_parent;