ipv6: syncookies: do not skip ->iif initialization (2bbdf389) · Commits · 戴 / test

When syncookies are in effect, req->iif is left uninitialized. In case of e.g. link-local addresses the route lookup then fails and no syn-ack is sent. Rearrange things so ->iif is also initialized in the syncookie case. want_cookie can only be true when the isn was zero, thus move the want_cookie check into the "!isn" branch. Cc: Glenn Griffin <ggriffin.kernel@gmail.com> Signed-off-by:

Florian Westphal <fw@strlen.de> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/ipv6/tcp_ipv6.c

+7 −6

Original line number	Diff line number	Diff line
		@@ -1272,10 +1272,7 @@ static int tcp_v6_conn_request(struct sock sk, struct sk_buff skb)
		if (!want_cookie)
		TCP_ECN_create_request(req, tcp_hdr(skb));

		if (want_cookie) {
		isn = cookie_v6_init_sequence(sk, skb, &req->mss);
		req->cookie_ts = tmp_opt.tstamp_ok;
		} else if (!isn) {
		if (!isn) {
		if (ipv6_opt_accepted(sk, skb) \|\|
		np->rxopt.bits.rxinfo \|\| np->rxopt.bits.rxoinfo \|\|
		np->rxopt.bits.rxhlim \|\| np->rxopt.bits.rxohlim) {
		@@ -1288,8 +1285,12 @@ static int tcp_v6_conn_request(struct sock sk, struct sk_buff skb)
		if (!sk->sk_bound_dev_if &&
		ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
		treq->iif = inet6_iif(skb);

		if (!want_cookie) {
		isn = tcp_v6_init_sequence(skb);
		} else {
		isn = cookie_v6_init_sequence(sk, skb, &req->mss);
		req->cookie_ts = tmp_opt.tstamp_ok;
		}
		}
		tcp_rsk(req)->snt_isn = isn;

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