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 00924C433F5 for ; Mon, 15 Nov 2021 17:46:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E1765633B4 for ; Mon, 15 Nov 2021 17:46:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238559AbhKORth (ORCPT ); Mon, 15 Nov 2021 12:49:37 -0500 Received: from mail.kernel.org ([198.145.29.99]:44996 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237450AbhKORVb (ORCPT ); Mon, 15 Nov 2021 12:21:31 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1733863279; Mon, 15 Nov 2021 17:16:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1636996570; bh=e0AixVREsKewyZWLJurhFn+CQrBq5HryW4idAq/VIao=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tSLdj78rbOoAy1BsMcd/89a9LWPYyWH72VMjhxh9F46CMpws4VyXj3KuBzgRDDOoz KA0dcGNft/32lwHDpOU8yRtoZI85SPwpGnkqJL2S1W2844l9IK+Jso5uzC29s2Q7zB SL/kPA56VeeocNNJYn04FXHe1EGRXsTh9ERhBjAI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Florian Westphal , David Ahern , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 171/355] vrf: run conntrack only in context of lower/physdev for locally generated packets Date: Mon, 15 Nov 2021 18:01:35 +0100 Message-Id: <20211115165319.321649118@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165313.549179499@linuxfoundation.org> References: <20211115165313.549179499@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Florian Westphal [ Upstream commit 8c9c296adfae9ea05f655d69e9f6e13daa86fb4a ] 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. One remaining issue is that a rule like output ... oif $vrfname notrack won't propagate to the second round because we can't tell 'notrack set via ruleset' and 'notrack set by vrf driver' apart. However, this isn't a regression: the 'notrack' removal happens instead of unconditional nf_reset_ct(). I'd also like to avoid leaking more vrf specific conditionals into the netfilter infra. 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 Acked-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- 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 f08ed52d51f3f..f436b8c130611 100644 --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -33,6 +33,7 @@ #include #include #include +#include #define DRV_NAME "vrf" #define DRV_VERSION "1.0" @@ -147,12 +148,26 @@ 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, NULL, 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); @@ -232,6 +247,8 @@ 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)) @@ -351,8 +368,7 @@ 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) @@ -366,7 +382,7 @@ 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; @@ -477,6 +493,8 @@ 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); @@ -584,7 +602,7 @@ static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *s bool is_v6gw = false; int ret = -EINVAL; - 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)) { @@ -712,6 +730,8 @@ 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); -- 2.33.0