Commit 9f7c02e0 authored by Eric Dumazet's avatar Eric Dumazet Committed by Jens Axboe
Browse files

nbd: restrict sockets to TCP and UDP 



Recently, syzbot started to abuse NBD with all kinds of sockets.

Commit cf1b2326 ("nbd: verify socket is supported during setup")
made sure the socket supported a shutdown() method.

Explicitely accept TCP and UNIX stream sockets.

Fixes: cf1b2326 ("nbd: verify socket is supported during setup")
Reported-by: default avatar <syzbot+e1cd6bd8493060bd701d@syzkaller.appspotmail.com>
Closes: https://lore.kernel.org/netdev/CANn89iJ+76eE3A_8S_zTpSyW5hvPRn6V57458hCZGY5hbH_bFA@mail.gmail.com/T/#m081036e8747cd7e2626c1da5d78c8b9d1e55b154


Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Richard W.M. Jones <rjones@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Yu Kuai <yukuai1@huaweicloud.com>
Cc: linux-block@vger.kernel.org
Cc: nbd@other.debian.org
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent bd9fd5be

drivers/block/nbd.c

+8 −0
Original line number Diff line number Diff line
@@ -1217,6 +1217,14 @@ static struct socket *nbd_get_socket(struct nbd_device *nbd, unsigned long fd, 
	if (!sock)

		return NULL;



	if (!sk_is_tcp(sock->sk) &&

	    !sk_is_stream_unix(sock->sk)) {

		dev_err(disk_to_dev(nbd->disk), "Unsupported socket: should be TCP or UNIX.\n");

		*err = -EINVAL;

		sockfd_put(sock);

		return NULL;

	}



	if (sock->ops->shutdown == sock_no_shutdown) {

		dev_err(disk_to_dev(nbd->disk), "Unsupported socket: shutdown callout must be supported.\n");

		*err = -EINVAL;