From: Liang He <windhl@xxxxxxx> [ Upstream commit 6030363199e3a6341afb467ddddbed56640cbf6a ] In vdc_port_probe(), we should check the return value of mdesc_grab() as it may return NULL, which can cause potential NPD bug. Fixes: 43fdf27470b2 ("[SPARC64]: Abstract out mdesc accesses for better MD update handling.") Signed-off-by: Liang He <windhl@xxxxxxx> Link: https://lore.kernel.org/r/20230315062032.1741692-1-windhl@xxxxxxx [axboe: style cleanup] Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/block/sunvdc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c index 4d4bb810c2aea..656d99faf40a2 100644 --- a/drivers/block/sunvdc.c +++ b/drivers/block/sunvdc.c @@ -964,6 +964,8 @@ static int vdc_port_probe(struct vio_dev *vdev, const struct vio_device_id *id) print_version(); hp = mdesc_grab(); + if (!hp) + return -ENODEV; err = -ENODEV; if ((vdev->dev_no << PARTITION_SHIFT) & ~(u64)MINORMASK) { -- 2.39.2