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ipv6: tcp: fix tcp_v6_conn_request()

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Since linux 2.6.26 (commit c6aefafb7e : Add IPv6 support to TCP SYN
cookies), we can drop a SYN packet reusing a TIME_WAIT socket.

(As a matter of fact we fail to send the SYNACK answer)

As the client resends its SYN packet after a one second timeout, we
accept it, because first packet removed the TIME_WAIT socket before
being dropped.

This probably explains why nobody ever noticed or complained.

Reported-by: Jesse Young <jlyo@jlyo.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2011-11-23 17:29:23 -05:00 committed by David S. Miller
parent 15ac2b08a2
commit 4d0fe50c75
1 changed files with 7 additions and 6 deletions
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13
net/ipv6/tcp_ipv6.c
View file

@ -1255,6 +1255,13 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
if (!want_cookie || tmp_opt.tstamp_ok)
TCP_ECN_create_request(req, tcp_hdr(skb));
treq->iif = sk->sk_bound_dev_if;
/* So that link locals have meaning */
if (!sk->sk_bound_dev_if &&
ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
treq->iif = inet6_iif(skb);
if (!isn) {
struct inet_peer *peer = NULL;
@ -1264,12 +1271,6 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
atomic_inc(&skb->users);
treq->pktopts = skb;
}
treq->iif = sk->sk_bound_dev_if;
/* So that link locals have meaning */
if (!sk->sk_bound_dev_if &&
ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
treq->iif = inet6_iif(skb);
if (want_cookie) {
isn = cookie_v6_init_sequence(sk, skb, &req->mss);