ceph: don't clobber i_snap_caps on non-I_NEW inode

We want the snapdir to mirror the non-snapped directory's attributes for
most things, but i_snap_caps represents the caps granted on the snapshot
directory by the MDS itself. A misbehaving MDS could issue different
caps for the snapdir and we lose them here.

Only reset i_snap_caps when the inode is I_NEW. Also, move the setting
of i_op and i_fop inside the if block since they should never change
anyway.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 4418d4be2907bc808a4b8d01496ff8387fc87ba6..2fd1c48ac5d7ce733cdbc0329e6d649692193855 100644 (file)
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -87,14 +87,15 @@ struct inode *ceph_get_snapdir(struct inode *parent)
        inode->i_mtime = parent->i_mtime;
        inode->i_ctime = parent->i_ctime;
        inode->i_atime = parent->i_atime;
-       inode->i_op = &ceph_snapdir_iops;
-       inode->i_fop = &ceph_snapdir_fops;
-       ci->i_snap_caps = CEPH_CAP_PIN; /* so we can open */
        ci->i_rbytes = 0;
        ci->i_btime = ceph_inode(parent)->i_btime;
 
-       if (inode->i_state & I_NEW)
+       if (inode->i_state & I_NEW) {
+               inode->i_op = &ceph_snapdir_iops;
+               inode->i_fop = &ceph_snapdir_fops;
+               ci->i_snap_caps = CEPH_CAP_PIN; /* so we can open */
                unlock_new_inode(inode);
+       }
 
        return inode;
 }