commit e0b760ff upstream.

The argument to locks_unlink_lock can't be just any pointer to a
pointer. It must be a pointer to the fl_next field in the previous
lock in the list.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>