ublk: santizize the arguments from userspace when adding a device

[ Upstream commit 8c84728 ]

Sanity check the values for queue depth and number of queues
we get from userspace when adding a device.

Signed-off-by: Ronnie Sahlberg <rsahlberg@whamcloud.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Fixes: 71f28f3 ("ublk_drv: add io_uring based userspace block driver")
Fixes: 62fe99c ("ublk: add read()/write() support for ublk char device")
Link: https://lore.kernel.org/r/20250619021031.181340-1-ronniesahlberg@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: RonnieSahlberg

drivers/block/ublk_drv.c

@@ -2323,6 +2323,9 @@ static int ublk_ctrl_add_dev(struct io_uring_cmd *cmd)
 	if (copy_from_user(&info, argp, sizeof(info)))
 		return -EFAULT;
 
+	if (info.queue_depth > UBLK_MAX_QUEUE_DEPTH || info.nr_hw_queues > UBLK_MAX_NR_QUEUES)
+		return -EINVAL;
+
 	if (capable(CAP_SYS_ADMIN))
 		info.flags &= ~UBLK_F_UNPRIVILEGED_DEV;
 	else if (!(info.flags & UBLK_F_UNPRIVILEGED_DEV))