mISDN: enforce CAP_NET_RAW for raw sockets

commit b91ee4a upstream.

When creating a raw AF_ISDN socket, CAP_NET_RAW needs to be checked
first.

Signed-off-by: Ori Nimron <orinimron123@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/isdn/mISDN/socket.c

@@ -763,6 +763,8 @@ base_sock_create(struct net *net, struct socket *sock, int protocol)
 
 	if (sock->type != SOCK_RAW)
 		return -ESOCKTNOSUPPORT;
+	if (!capable(CAP_NET_RAW))
+		return -EPERM;
 
 	sk = sk_alloc(net, PF_ISDN, GFP_KERNEL, &mISDN_proto);
 	if (!sk)