add WARN_ON()

Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

drivers/block/floppy.c

@@ -3497,7 +3497,7 @@ static int fd_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
 	    ((cmd & 0x80) && !capable(CAP_SYS_ADMIN)))
 		return -EPERM;
 
-	if (size < 0 || size > sizeof(inparam))
+	if (WARN_ON(size < 0 || size > sizeof(inparam)))
 		return -EINVAL;
 
 	/* copyin */