From mboxrd@z Thu Jan 1 00:00:00 1970 From: KOVACS Krisztian Subject: [PATCH] netfilter: xt_socket: fix transparent match for IPv6 request sockets Date: Fri, 23 Sep 2016 11:27:42 +0200 Message-ID: <20160923092742.88262-1-hidden@balabit.com> Cc: Alex Badics , Eric Dumazet , KOVACS Krisztian To: Pablo Neira Ayuso , netfilter-devel@vger.kernel.org, netdev@vger.kernel.org Return-path: Sender: netfilter-devel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org The introduction of TCP_NEW_SYN_RECV state, and the addition of request sockets to the ehash table seems to have broken the --transparent option of the socket match for IPv6 (around commit a9407000). Now that the socket lookup finds the TCP_NEW_SYN_RECV socket instead of the listener, the --transparent option tries to match on the no_srccheck flag of the request socket. Unfortunately, that flag was only set for IPv4 sockets in tcp_v4_init_req() by copying the transparent flag of the listener socket. This effectively causes '-m socket --transparent' not match on the ACK packet sent by the client in a TCP handshake. Based on the suggestion from Eric Dumazet, this change moves the code initializing no_srccheck to tcp_conn_request(), rendering the above scenario working again. Fixes: a940700003 ("netfilter: xt_socket: prepare for TCP_NEW_SYN_RECV support") Signed-off-by: Alex Badics Signed-off-by: KOVACS Krisztian --- net/ipv4/tcp_input.c | 1 + net/ipv4/tcp_ipv4.c | 1 - 2 files changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 3ebf45b..1fb2e82 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -6260,6 +6260,7 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops, tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; tcp_openreq_init(req, &tmp_opt, skb, sk); + inet_rsk(req)->no_srccheck = inet_sk(sk)->transparent; /* Note: tcp_v6_init_req() might override ir_iif for link locals */ inet_rsk(req)->ir_iif = inet_request_bound_dev_if(sk, skb); diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 7158d4f..b448eb9 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1195,7 +1195,6 @@ static void tcp_v4_init_req(struct request_sock *req, sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr); sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr); - ireq->no_srccheck = inet_sk(sk_listener)->transparent; ireq->opt = tcp_v4_save_options(skb); } -- 2.10.0