From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66A76C35247 for ; Mon, 3 Feb 2020 16:22:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 387A82080D for ; Mon, 3 Feb 2020 16:22:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580746931; bh=PBpj83y6P2Oz1vGiFYaOARH393JtewVbCmCv5KbtJAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ndc8WeHywvAKBqv/ajiwlTu2ojfK2ISCwHxvgfwTRGZ3lxrde+JJ9EbpDJyC2LWeh Vy72axDfG3hBSp+CC+1XiEdDs4RH+6W5TDa1u1ZHy9hDa2QhGYaip2TCITv9Ies8ss /+WYBDBRxDGBQM3c9PDRXOXI+KZ13Hci5l1RqtOQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729207AbgBCQVv (ORCPT ); Mon, 3 Feb 2020 11:21:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:33798 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729185AbgBCQVp (ORCPT ); Mon, 3 Feb 2020 11:21:45 -0500 Received: from localhost (unknown [104.132.45.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 475912080C; Mon, 3 Feb 2020 16:21:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580746904; bh=PBpj83y6P2Oz1vGiFYaOARH393JtewVbCmCv5KbtJAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ulmZqgT54XZXxoZFDJDbasQSClbTqiomVHI/8opeOIJf8Cjq9K6FmvtPDY4E0LsGo 4C5sxl0Z0SKKQnnfX1tifVzPICi7XPSWonOZhXvMxs3VBojTRjljU0VENPHUhAgplN jiySncwhSEntw3xzGXOlnqHx0IDi/SFcXFl5tf0Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicolas Dichtel , Steffen Klassert , Sasha Levin Subject: [PATCH 4.4 39/53] vti[6]: fix packet tx through bpf_redirect() Date: Mon, 3 Feb 2020 16:19:31 +0000 Message-Id: <20200203161909.898535885@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200203161902.714326084@linuxfoundation.org> References: <20200203161902.714326084@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nicolas Dichtel [ Upstream commit 95224166a9032ff5d08fca633d37113078ce7d01 ] With an ebpf program that redirects packets through a vti[6] interface, the packets are dropped because no dst is attached. This could also be reproduced with an AF_PACKET socket, with the following python script (vti1 is an ip_vti interface): import socket send_s = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, 0) # scapy # p = IP(src='10.100.0.2', dst='10.200.0.1')/ICMP(type='echo-request') # raw(p) req = b'E\x00\x00\x1c\x00\x01\x00\x00@\x01e\xb2\nd\x00\x02\n\xc8\x00\x01\x08\x00\xf7\xff\x00\x00\x00\x00' send_s.sendto(req, ('vti1', 0x800, 0, 0)) Signed-off-by: Nicolas Dichtel Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin --- net/ipv4/ip_vti.c | 13 +++++++++++-- net/ipv6/ip6_vti.c | 13 +++++++++++-- 2 files changed, 22 insertions(+), 4 deletions(-) diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c index bbcbbc1cc2cc6..42dbd280dc9be 100644 --- a/net/ipv4/ip_vti.c +++ b/net/ipv4/ip_vti.c @@ -195,8 +195,17 @@ static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev, int err; if (!dst) { - dev->stats.tx_carrier_errors++; - goto tx_error_icmp; + struct rtable *rt; + + fl->u.ip4.flowi4_oif = dev->ifindex; + fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC; + rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4); + if (IS_ERR(rt)) { + dev->stats.tx_carrier_errors++; + goto tx_error_icmp; + } + dst = &rt->dst; + skb_dst_set(skb, dst); } dst_hold(dst); diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c index 51da5987952ce..623963a2d8a68 100644 --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -441,8 +441,17 @@ vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) int err = -1; int mtu; - if (!dst) - goto tx_err_link_failure; + if (!dst) { + fl->u.ip6.flowi6_oif = dev->ifindex; + fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC; + dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6); + if (dst->error) { + dst_release(dst); + dst = NULL; + goto tx_err_link_failure; + } + skb_dst_set(skb, dst); + } dst_hold(dst); dst = xfrm_lookup(t->net, dst, fl, NULL, 0); -- 2.20.1