[PATCH] block: nbd: fix sanity check for first_minor

[Yan, Zheng]

From: "Yan, Zheng" <yanzheng03@xxxxxxxxxxxx>

Device's minor is a 20-bits number, max value is 0xfffff.

Fixes: b1a811633f ("block: nbd: add sanity check for first_minor").
Signed-off-by: "Yan, Zheng" <yanzheng03@xxxxxxxxxxxx>
---
 drivers/block/nbd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 1183f7872b71..53cd038c96e9 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1753,7 +1753,7 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 	 * byte in __device_add_disk().
 	 */
 	disk->first_minor = index << part_shift;
-	if (disk->first_minor > 0xff) {
+	if (disk->first_minor > MINORMASK) {
 		err = -EINVAL;
 		goto out_free_idr;
 	}
-- 
2.12.2