From patchwork Fri Feb 4 13:58:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guillaume Nault X-Patchwork-Id: 12735111 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 152EAC433EF for ; Fri, 4 Feb 2022 13:58:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359155AbiBDN62 (ORCPT ); Fri, 4 Feb 2022 08:58:28 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:38596 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359164AbiBDN6V (ORCPT ); Fri, 4 Feb 2022 08:58:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643983101; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=huLoFadblEn2s3rt9PCLve07r8DRe9hm65RauLtf9Y8=; b=dlGE2ZyCPTnbdXXpZf/voWFK9TeQXQrFgW4MJVycGuC+rEvHh5t87C9ID67wxXpdYH3O6/ 1Av7kSqWDFF2uj3Wog2C5AIo5tgrqwOpwzAAeCCzzMR5pH8/WiQs9e1AZ5jrjKRz8pNPwm Igh3I7kOmtyAZAhhl9zc0gy1gGWYkbc= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-674-Sl2TAusrNCyGaSGWGc33ug-1; Fri, 04 Feb 2022 08:58:20 -0500 X-MC-Unique: Sl2TAusrNCyGaSGWGc33ug-1 Received: by mail-wr1-f71.google.com with SMTP id e2-20020adfa442000000b001e2dd248341so592590wra.20 for ; Fri, 04 Feb 2022 05:58:20 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=huLoFadblEn2s3rt9PCLve07r8DRe9hm65RauLtf9Y8=; b=yJc2GRdXCfQ2jaSEXBo+i+CCjmS33kxu453eqMz8eqQ2CHvgcqkel9vE5t+hano0X3 Tc5Tq1Lf7as9b9jmUZ+6o/NU4rdOlYd6IzINMB3aRoJw07QckXgLJexWmYTu63otQdi+ 3bOrnZ2HozwBgqwch3t4FajUkBXreiI3QA5AUaImgjFPVtIK8IE884JxC1+I66CrPtWI V6s4BkNQPG27yyuawPlh+nl5PvD+1RFGsoNs1KXCbvOc1XPWkKIjjmkm6JKt0lIoOWd+ g7NI5IxymfUxJ/8kqqPqWrzIARUOVwYXPBmA1vsq+mgTLggTtL1oGWFGU6qp7sQPSoeN 4mNA== X-Gm-Message-State: AOAM532feN9yqIDNI5qmMiuRjxdOfm9TrXgaxBl2NriLfZGAKQnm4xpR yZhuK+V2bBXuL60w9zgJjQYj7KPvjLVWkwlaU9E6QVSy6f8Bzij31c0/xfsyEzC6LRiFz5u4mAP FBII1dggN/KqWdLPx X-Received: by 2002:adf:f750:: with SMTP id z16mr786425wrp.239.1643983099111; Fri, 04 Feb 2022 05:58:19 -0800 (PST) X-Google-Smtp-Source: ABdhPJz9n7xqbaODP/c2niZ8sZmsya6PVRtmFseh5p6sdFV0nfmo3BUQb4qtexbScYv/kP0iTRNYQg== X-Received: by 2002:adf:f750:: with SMTP id z16mr786414wrp.239.1643983098926; Fri, 04 Feb 2022 05:58:18 -0800 (PST) Received: from pc-4.home (2a01cb058918ce00dd1a5a4f9908f2d5.ipv6.abo.wanadoo.fr. [2a01:cb05:8918:ce00:dd1a:5a4f:9908:f2d5]) by smtp.gmail.com with ESMTPSA id o14sm2280445wry.104.2022.02.04.05.58.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Feb 2022 05:58:18 -0800 (PST) Date: Fri, 4 Feb 2022 14:58:16 +0100 From: Guillaume Nault To: David Miller , Jakub Kicinski Cc: netdev@vger.kernel.org, Hideaki YOSHIFUJI , David Ahern , Toke =?iso-8859-1?q?H=F8iland-J=F8rgensen?= , Shuah Khan , linux-kselftest@vger.kernel.org, Russell Strong , Dave Taht Subject: [PATCH net-next 3/4] ipv4: Reject routes specifying ECN bits in rtm_tos Message-ID: References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Use the new dscp_t type to replace the fc_tos field of fib_config, to ensure IPv4 routes aren't influenced by ECN bits when configured with non-zero rtm_tos. Before this patch, IPv4 routes specifying an rtm_tos with some of the ECN bits set were accepted. However they wouldn't work (never match) as IPv4 normally clears the ECN bits with IPTOS_RT_MASK before doing a FIB lookup (although a few buggy code paths don't). After this patch, IPv4 routes specifying an rtm_tos with any ECN bit set is rejected. Note: IPv6 routes ignore rtm_tos altogether, any rtm_tos is accepted, but treated as if it were 0. Signed-off-by: Guillaume Nault --- Shuah, FYI, this is the patch I was refering to in our discussion about testing invalid tos values: https://lore.kernel.org/netdev/20220202232555.GC15826@pc-4.home/ include/net/ip_fib.h | 3 +- net/ipv4/fib_frontend.c | 11 +++- net/ipv4/fib_trie.c | 7 ++- tools/testing/selftests/net/fib_tests.sh | 76 ++++++++++++++++++++++++ 4 files changed, 93 insertions(+), 4 deletions(-) diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index c4297704bbcb..6a82bcb8813b 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -24,7 +25,7 @@ struct fib_config { u8 fc_dst_len; - u8 fc_tos; + dscp_t fc_dscp; u8 fc_protocol; u8 fc_scope; u8 fc_type; diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 4d61ddd8a0ec..c60e1d1ed2b0 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -32,6 +32,7 @@ #include #include +#include #include #include #include @@ -735,8 +736,16 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, memset(cfg, 0, sizeof(*cfg)); rtm = nlmsg_data(nlh); + + if (!inet_validate_dscp(rtm->rtm_tos)) { + NL_SET_ERR_MSG(extack, + "Invalid dsfield (tos): ECN bits must be 0"); + err = -EINVAL; + goto errout; + } + cfg->fc_dscp = inet_dsfield_to_dscp(rtm->rtm_tos); + cfg->fc_dst_len = rtm->rtm_dst_len; - cfg->fc_tos = rtm->rtm_tos; cfg->fc_table = rtm->rtm_table; cfg->fc_protocol = rtm->rtm_protocol; cfg->fc_scope = rtm->rtm_scope; diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index 8060524f4256..d937eeebb812 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -61,6 +61,7 @@ #include #include #include +#include #include #include #include @@ -1210,9 +1211,9 @@ int fib_table_insert(struct net *net, struct fib_table *tb, struct fib_info *fi; u8 plen = cfg->fc_dst_len; u8 slen = KEYLENGTH - plen; - u8 tos = cfg->fc_tos; u32 key; int err; + u8 tos; key = ntohl(cfg->fc_dst); @@ -1227,6 +1228,7 @@ int fib_table_insert(struct net *net, struct fib_table *tb, goto err; } + tos = inet_dscp_to_dsfield(cfg->fc_dscp); l = fib_find_node(t, &tp, key); fa = l ? fib_find_alias(&l->leaf, slen, tos, fi->fib_priority, tb->tb_id, false) : NULL; @@ -1703,8 +1705,8 @@ int fib_table_delete(struct net *net, struct fib_table *tb, struct key_vector *l, *tp; u8 plen = cfg->fc_dst_len; u8 slen = KEYLENGTH - plen; - u8 tos = cfg->fc_tos; u32 key; + u8 tos; key = ntohl(cfg->fc_dst); @@ -1715,6 +1717,7 @@ int fib_table_delete(struct net *net, struct fib_table *tb, if (!l) return -ESRCH; + tos = inet_dscp_to_dsfield(cfg->fc_dscp); fa = fib_find_alias(&l->leaf, slen, tos, 0, tb->tb_id, false); if (!fa) return -ESRCH; diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh index 996af1ae3d3d..bb73235976b3 100755 --- a/tools/testing/selftests/net/fib_tests.sh +++ b/tools/testing/selftests/net/fib_tests.sh @@ -1447,6 +1447,81 @@ ipv4_local_rt_cache() log_test $? 0 "Cached route removed from VRF port device" } +ipv4_rt_dsfield() +{ + echo + echo "IPv4 route with dsfield tests" + + run_cmd "$IP route flush 172.16.102.0/24" + + # New routes should reject dsfield options that interfere with ECN + run_cmd "$IP route add 172.16.102.0/24 dsfield 0x01 via 172.16.101.2" + log_test $? 2 "Reject route with dsfield 0x01" + + run_cmd "$IP route add 172.16.102.0/24 dsfield 0x02 via 172.16.101.2" + log_test $? 2 "Reject route with dsfield 0x02" + + run_cmd "$IP route add 172.16.102.0/24 dsfield 0x03 via 172.16.101.2" + log_test $? 2 "Reject route with dsfield 0x03" + + # A generic route that doesn't take DSCP into account + run_cmd "$IP route add 172.16.102.0/24 via 172.16.101.2" + + # A more specific route for DSCP 0x10 + run_cmd "$IP route add 172.16.102.0/24 dsfield 0x10 via 172.16.103.2" + + # DSCP 0x10 should match the specific route, no matter the ECN bits + $IP route get fibmatch 172.16.102.1 dsfield 0x10 | \ + grep -q "via 172.16.103.2" + log_test $? 0 "IPv4 route with DSCP and ECN:Not-ECT" + + $IP route get fibmatch 172.16.102.1 dsfield 0x11 | \ + grep -q "via 172.16.103.2" + log_test $? 0 "IPv4 route with DSCP and ECN:ECT(1)" + + $IP route get fibmatch 172.16.102.1 dsfield 0x12 | \ + grep -q "via 172.16.103.2" + log_test $? 0 "IPv4 route with DSCP and ECN:ECT(0)" + + $IP route get fibmatch 172.16.102.1 dsfield 0x13 | \ + grep -q "via 172.16.103.2" + log_test $? 0 "IPv4 route with DSCP and ECN:CE" + + # Unknown DSCP should match the generic route, no matter the ECN bits + $IP route get fibmatch 172.16.102.1 dsfield 0x14 | \ + grep -q "via 172.16.101.2" + log_test $? 0 "IPv4 route with unknown DSCP and ECN:Not-ECT" + + $IP route get fibmatch 172.16.102.1 dsfield 0x15 | \ + grep -q "via 172.16.101.2" + log_test $? 0 "IPv4 route with unknown DSCP and ECN:ECT(1)" + + $IP route get fibmatch 172.16.102.1 dsfield 0x16 | \ + grep -q "via 172.16.101.2" + log_test $? 0 "IPv4 route with unknown DSCP and ECN:ECT(0)" + + $IP route get fibmatch 172.16.102.1 dsfield 0x17 | \ + grep -q "via 172.16.101.2" + log_test $? 0 "IPv4 route with unknown DSCP and ECN:CE" + + # Null DSCP should match the generic route, no matter the ECN bits + $IP route get fibmatch 172.16.102.1 dsfield 0x00 | \ + grep -q "via 172.16.101.2" + log_test $? 0 "IPv4 route with no DSCP and ECN:Not-ECT" + + $IP route get fibmatch 172.16.102.1 dsfield 0x01 | \ + grep -q "via 172.16.101.2" + log_test $? 0 "IPv4 route with no DSCP and ECN:ECT(1)" + + $IP route get fibmatch 172.16.102.1 dsfield 0x02 | \ + grep -q "via 172.16.101.2" + log_test $? 0 "IPv4 route with no DSCP and ECN:ECT(0)" + + $IP route get fibmatch 172.16.102.1 dsfield 0x03 | \ + grep -q "via 172.16.101.2" + log_test $? 0 "IPv4 route with no DSCP and ECN:CE" +} + ipv4_route_test() { route_setup @@ -1454,6 +1529,7 @@ ipv4_route_test() ipv4_rt_add ipv4_rt_replace ipv4_local_rt_cache + ipv4_rt_dsfield route_cleanup }