if (sk->sk_type != SOCK_DGRAM)
return -EPROTONOSUPPORT;
+ if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
+ return -EPROTONOSUPPORT;
+
if ((encap == L2TP_ENCAPTYPE_UDP && sk->sk_protocol != IPPROTO_UDP) ||
(encap == L2TP_ENCAPTYPE_IP && sk->sk_protocol != IPPROTO_L2TP))
return -EPROTONOSUPPORT;