diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 25e81b1a59a5..bc3ab98855cf 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1744,7 +1744,17 @@ static int nbd_dev_add(int index)
 	refcount_set(&nbd->refs, 1);
 	INIT_LIST_HEAD(&nbd->list);
 	disk->major = NBD_MAJOR;
+
+	/* Too big first_minor can cause duplicate creation of
+	 * sysfs files/links, since first_minor will be truncated to
+	 * byte in __device_add_disk().
+	 */
 	disk->first_minor = index << part_shift;
+	if (disk->first_minor > 0xff) {
+		err = -EINVAL;
+		goto out_free_idr;
+	}
+
 	disk->fops = &nbd_fops;
 	disk->private_data = nbd;
 	sprintf(disk->disk_name, "nbd%d", index);