NFSv4.x: Fix handling of partially delegated locks

commit c5a2a15f8146fdfe45078df7873a6dc1006b3869 upstream.

If a NFS client receives a delegation for a file after it has taken
a lock on that file, we can currently end up in a situation where
we mistakenly skip unlocking that file.

The following patch swaps an erroneous check in nfs4_proc_unlck for
whether or not the file has a delegation to one which checks whether
or not we hold a lock stateid for that file.

Reported-by: Chuck Lever <Chuck.Lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Chuck Lever <Chuck.Lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index c7856a1cef0698fa40e1643737bb8964aa4eaf6f..008640175152e0e90566acc15042caf0fc2e9609 100644 (file)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -4553,9 +4553,9 @@ static int nfs4_proc_unlck(struct nfs4_state *state, int cmd, struct file_lock *
        if (status != 0)
                goto out;
        /* Is this a delegated lock? */
-       if (test_bit(NFS_DELEGATED_STATE, &state->flags))
-               goto out;
        lsp = request->fl_u.nfs4_fl.owner;
+       if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) == 0)
+               goto out;
        seqid = nfs_alloc_seqid(&lsp->ls_seqid, GFP_KERNEL);
        status = -ENOMEM;
        if (seqid == NULL)