nfsd4: warn on finding lockowner without stateid's

commit 27b11428b7de097c42f205beabb1764f4365443b upstream.

The current code assumes a one-to-one lockowner<->lock stateid
correspondance.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index f90b197ceffae8b841bf856736c7f12aa0c11907..38aca5d94ada1ea91f4200e9dd3f523843837cde 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3918,6 +3918,10 @@ static bool same_lockowner_ino(struct nfs4_lockowner *lo, struct inode *inode, c
 
        if (!same_owner_str(&lo->lo_owner, owner, clid))
                return false;
+       if (list_empty(&lo->lo_owner.so_stateids)) {
+               WARN_ON_ONCE(1);
+               return false;
+       }
        lst = list_first_entry(&lo->lo_owner.so_stateids,
                               struct nfs4_ol_stateid, st_perstateowner);
        return lst->st_file->fi_inode == inode;