netfilter: tproxy: nf_tproxy_assign_sock() can handle tw sockets

transparent field of a socket is either inet_twsk(sk)->tw_transparent
for timewait sockets, or inet_sk(sk)->transparent for other sockets
(TCP/UDP).

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/netfilter/nf_tproxy_core.c

@@ -70,7 +70,11 @@ nf_tproxy_destructor(struct sk_buff *skb)
 int
 nf_tproxy_assign_sock(struct sk_buff *skb, struct sock *sk)
 {
-	if (inet_sk(sk)->transparent) {
+	bool transparent = (sk->sk_state == TCP_TIME_WAIT) ?
+				inet_twsk(sk)->tw_transparent :
+				inet_sk(sk)->transparent;
+
+	if (transparent) {
 		skb_orphan(skb);
 		skb->sk = sk;
 		skb->destructor = nf_tproxy_destructor;