From patchwork Thu Oct 21 14:48:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Westphal X-Patchwork-Id: 12575347 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B386C433EF for ; Thu, 21 Oct 2021 14:49:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 16A5F61251 for ; Thu, 21 Oct 2021 14:49:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231599AbhJUOve (ORCPT ); Thu, 21 Oct 2021 10:51:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231574AbhJUOvb (ORCPT ); Thu, 21 Oct 2021 10:51:31 -0400 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:12e:520::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 881F3C0613B9; Thu, 21 Oct 2021 07:49:15 -0700 (PDT) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1mdZNZ-00015I-VE; Thu, 21 Oct 2021 16:49:13 +0200 From: Florian Westphal To: Cc: netfilter-devel@vger.kernel.org, dsahern@kernel.org, pablo@netfilter.org, crosser@average.org, lschlesinger@drivenets.com, Florian Westphal Subject: [PATCH net-next 2/2] vrf: run conntrack only in context of lower/physdev for locally generated packets Date: Thu, 21 Oct 2021 16:48:57 +0200 Message-Id: <20211021144857.29714-3-fw@strlen.de> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211021144857.29714-1-fw@strlen.de> References: <20211021144857.29714-1-fw@strlen.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The VRF driver invokes netfilter for output+postrouting hooks so that users can create rules that check for 'oif $vrf' rather than lower device name. This is a problem when NAT rules are configured. To avoid any conntrack involvement in round 1, tag skbs as 'untracked' to prevent conntrack from picking them up. This gets cleared before the packet gets handed to the ip stack so conntrack will be active on the second iteration. For ingress, conntrack has already been done before the packet makes it to the vrf driver, with this patch egress does connection tracking with lower/physical device as well. Signed-off-by: Florian Westphal --- drivers/net/vrf.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c index bf2fac913942..c813d03159bf 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -35,6 +35,7 @@ #include #include #include +#include #define DRV_NAME "vrf" #define DRV_VERSION "1.1" @@ -424,12 +425,26 @@ static int vrf_local_xmit(struct sk_buff *skb, struct net_device *dev, return NETDEV_TX_OK; } +static void vrf_nf_set_untracked(struct sk_buff *skb) +{ + if (skb_get_nfct(skb) == 0) + nf_ct_set(skb, 0, IP_CT_UNTRACKED); +} + +static void vrf_nf_reset_ct(struct sk_buff *skb) +{ + if (skb_get_nfct(skb) == IP_CT_UNTRACKED) + nf_reset_ct(skb); +} + #if IS_ENABLED(CONFIG_IPV6) static int vrf_ip6_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) { int err; + vrf_nf_reset_ct(skb); + err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb, NULL, skb_dst(skb)->dev, dst_output); @@ -508,6 +523,8 @@ static int vrf_ip_local_out(struct net *net, struct sock *sk, { int err; + vrf_nf_reset_ct(skb); + err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk, skb, NULL, skb_dst(skb)->dev, dst_output); if (likely(err == 1)) @@ -626,8 +643,7 @@ static void vrf_finish_direct(struct sk_buff *skb) skb_pull(skb, ETH_HLEN); } - /* reset skb device */ - nf_reset_ct(skb); + vrf_nf_reset_ct(skb); } #if IS_ENABLED(CONFIG_IPV6) @@ -641,7 +657,7 @@ static int vrf_finish_output6(struct net *net, struct sock *sk, struct neighbour *neigh; int ret; - nf_reset_ct(skb); + vrf_nf_reset_ct(skb); skb->protocol = htons(ETH_P_IPV6); skb->dev = dev; @@ -752,6 +768,8 @@ static struct sk_buff *vrf_ip6_out_direct(struct net_device *vrf_dev, skb->dev = vrf_dev; + vrf_nf_set_untracked(skb); + err = nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb, NULL, vrf_dev, vrf_ip6_out_direct_finish); @@ -858,7 +876,7 @@ static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *s struct neighbour *neigh; bool is_v6gw = false; - nf_reset_ct(skb); + vrf_nf_reset_ct(skb); /* Be paranoid, rather than too clever. */ if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) { @@ -980,6 +998,8 @@ static struct sk_buff *vrf_ip_out_direct(struct net_device *vrf_dev, skb->dev = vrf_dev; + vrf_nf_set_untracked(skb); + err = nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk, skb, NULL, vrf_dev, vrf_ip_out_direct_finish);