rcv_saddr
__be32 rcv_saddr;
tb2->rcv_saddr = sk->sk_rcv_saddr;
return tb2->rcv_saddr == sk->sk_rcv_saddr;
return tb->rcv_saddr == 0;
__be32 rcv_saddr = READ_ONCE(isk->inet_rcv_saddr);
ident, &rcv_saddr,
if (rcv_saddr && rcv_saddr != ip_hdr(skb)->daddr)