From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Mack Subject: [PATCH RFC 3/3] net: tcp_ipv4: re-run netfilter chains for marked skbs Date: Wed, 16 Sep 2015 17:43:00 +0200 Message-ID: <1442418180-14322-4-git-send-email-daniel@zonque.org> References: <1442418180-14322-1-git-send-email-daniel@zonque.org> Cc: daniel@iogearbox.net, netfilter-devel@vger.kernel.org, netdev@vger.kernel.org, fw@strlen.de, balazs.scheidler@balabit.com, Daniel Mack To: pablo@netfilter.org Return-path: In-Reply-To: <1442418180-14322-1-git-send-email-daniel@zonque.org> Sender: netdev-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org When an skb has been marked for later re-iteration through netfilter, do that after __inet_lookup_skb() has been called. This allows packets sent to unconnected sockets to be filtered reliably. Note that this will never happen for subsequent packets in the same stream, as skb->sk will be set due to early demux, and hence skb->nf_postponed will remain 0. Signed-off-by: Daniel Mack --- net/ipv4/tcp_ipv4.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 93898e0..61e0cb4 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -78,6 +78,7 @@ #include #include +#include #include #include #include @@ -1594,6 +1595,15 @@ int tcp_v4_rcv(struct sk_buff *skb) if (!sk) goto no_tcp_socket; + if (unlikely(skb->nf_postponed)) { + ret = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_IN, sk, + skb, skb->dev, NULL, NULL); + if (ret != 1) { + sock_put(sk); + return 0; + } + } + process: if (sk->sk_state == TCP_TIME_WAIT) goto do_time_wait; -- 2.5.0