void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
{
	struct inet_sock *inet = inet_sk(sk);
	struct sock_exterr_skb *serr;
	struct iphdr *iph;
	struct sk_buff *skb;

	if (!inet->recverr)
		return;

	skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
	if (!skb)
		return;

	skb_put(skb, sizeof(struct iphdr));
	skb_reset_network_header(skb);
	iph = ip_hdr(skb);
	iph->daddr = daddr;

	serr = SKB_EXT_ERR(skb);
	serr->ee.ee_errno = err;
	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
	serr->ee.ee_type = 0;
	serr->ee.ee_code = 0;
	serr->ee.ee_pad = 0;
	serr->ee.ee_info = info;
	serr->ee.ee_data = 0;
	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
	serr->port = port;

	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
	skb_reset_transport_header(skb);

	if (sock_queue_err_skb(sk, skb))
		kfree_skb(skb);
}
Unknown