From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Manning Subject: [PATCH net-next v3 3/9] net: ensure unbound datagram socket to be chosen when not in a VRF Date: Thu, 4 Oct 2018 16:12:08 +0100 Message-ID: <20181004151214.8522-4-mmanning@vyatta.att-mail.com> References: <20181004151214.8522-1-mmanning@vyatta.att-mail.com> To: netdev@vger.kernel.org Return-path: Received: from mx0a-00191d01.pphosted.com ([67.231.149.140]:35480 "EHLO mx0a-00191d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727561AbeJDWHF (ORCPT ); Thu, 4 Oct 2018 18:07:05 -0400 Received: from pps.filterd (m0049287.ppops.net [127.0.0.1]) by m0049287.ppops.net-00191d01. (8.16.0.22/8.16.0.22) with SMTP id w94F9qNk013953 for ; Thu, 4 Oct 2018 11:13:21 -0400 Received: from tlpd255.enaf.dadc.sbc.com (sbcsmtp3.sbc.com [144.160.112.28]) by m0049287.ppops.net-00191d01. with ESMTP id 2mwjsmn9wc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 04 Oct 2018 11:13:17 -0400 Received: from enaf.dadc.sbc.com (localhost [127.0.0.1]) by tlpd255.enaf.dadc.sbc.com (8.14.5/8.14.5) with ESMTP id w94FCa9p129013 for ; Thu, 4 Oct 2018 10:12:38 -0500 Received: from zlp30497.vci.att.com (zlp30497.vci.att.com [135.46.181.156]) by tlpd255.enaf.dadc.sbc.com (8.14.5/8.14.5) with ESMTP id w94FCWmx128834 for ; Thu, 4 Oct 2018 10:12:32 -0500 Received: from zlp30497.vci.att.com (zlp30497.vci.att.com [127.0.0.1]) by zlp30497.vci.att.com (Service) with ESMTP id 89E494014203 for ; Thu, 4 Oct 2018 15:12:32 +0000 (GMT) Received: from clpi183.sldc.sbc.com (unknown [135.41.1.46]) by zlp30497.vci.att.com (Service) with ESMTP id 69C1540141F7 for ; Thu, 4 Oct 2018 15:12:32 +0000 (GMT) Received: from sldc.sbc.com (localhost [127.0.0.1]) by clpi183.sldc.sbc.com (8.14.5/8.14.5) with ESMTP id w94FCVUB015605 for ; Thu, 4 Oct 2018 10:12:32 -0500 Received: from mail.eng.vyatta.net (mail.eng.vyatta.net [10.156.50.82]) by clpi183.sldc.sbc.com (8.14.5/8.14.5) with ESMTP id w94FCPKR015193 for ; Thu, 4 Oct 2018 10:12:25 -0500 Received: from MM-7520.vyatta.net (unknown [10.156.47.144]) by mail.eng.vyatta.net (Postfix) with ESMTPA id B4990360350 for ; Thu, 4 Oct 2018 08:12:24 -0700 (PDT) In-Reply-To: <20181004151214.8522-1-mmanning@vyatta.att-mail.com> Sender: netdev-owner@vger.kernel.org List-ID: Ensure an unbound datagram skt is chosen when not in a VRF. The check for a device match in compute_score() for UDP must be performed when there is no device match. For this, a failure is returned when there is no device match. This ensures that bound sockets are never selected, even if there is no unbound socket. Allow IPv6 packets to be sent over a datagram skt bound to a VRF. These packets are currently blocked, as flowi6_oif was set to that of the master vrf device, and the ipi6_ifindex is that of the slave device. Allow these packets to be sent by checking the device with ipi6_ifindex has the same L3 scope as that of the bound device of the skt, which is the master vrf device. Note that this check always succeeds if the skt is unbound. Even though the right datagram skt is now selected by compute_score(), a different skt is being returned that is bound to the wrong vrf. The difference between these and stream sockets is the handling of the skt option for SO_REUSEPORT. While the handling when adding a skt for reuse correctly checks that the bound device of the skt is a match, the skts in the hashslot are already incorrect. So for the same hash, a skt for the wrong vrf may be selected for the required port. The root cause is that the skt is immediately placed into a slot when it is created, but when the skt is then bound using SO_BINDTODEVICE, it remains in the same slot. The solution is to move the skt to the correct slot by forcing a rehash. Signed-off-by: Mike Manning --- include/net/udp.h | 11 +++++++++++ net/core/sock.c | 2 ++ net/ipv4/udp.c | 15 ++++++--------- net/ipv6/datagram.c | 5 ++++- net/ipv6/udp.c | 14 +++++--------- 5 files changed, 28 insertions(+), 19 deletions(-) diff --git a/include/net/udp.h b/include/net/udp.h index 8482a990b0bb..1e4fb8feaf50 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -252,6 +252,17 @@ static inline int udp_rqueue_get(struct sock *sk) return sk_rmem_alloc_get(sk) - READ_ONCE(udp_sk(sk)->forward_deficit); } +static inline bool udp_sk_bound_dev_eq(struct net *net, int bound_dev_if, + int dif, int sdif) +{ +#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) + return inet_bound_dev_eq(net->ipv4.sysctl_udp_l3mdev_accept, + bound_dev_if, dif, sdif); +#else + return inet_bound_dev_eq(1, bound_dev_if, dif, sdif); +#endif +} + /* net/ipv4/udp.c */ void udp_destruct_sock(struct sock *sk); void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len); diff --git a/net/core/sock.c b/net/core/sock.c index 3730eb855095..da1cbb88a6bf 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -567,6 +567,8 @@ static int sock_setbindtodevice(struct sock *sk, char __user *optval, lock_sock(sk); sk->sk_bound_dev_if = index; + if (sk->sk_prot->rehash) + sk->sk_prot->rehash(sk); sk_dst_reset(sk); release_sock(sk); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 3386b3b0218c..0559a7f4c83a 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -371,6 +371,7 @@ static int compute_score(struct sock *sk, struct net *net, { int score; struct inet_sock *inet; + bool dev_match; if (!net_eq(sock_net(sk), net) || udp_sk(sk)->udp_port_hash != hnum || @@ -398,15 +399,11 @@ static int compute_score(struct sock *sk, struct net *net, score += 4; } - if (sk->sk_bound_dev_if || exact_dif) { - bool dev_match = (sk->sk_bound_dev_if == dif || - sk->sk_bound_dev_if == sdif); - - if (!dev_match) - return -1; - if (sk->sk_bound_dev_if) - score += 4; - } + dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, + dif, sdif); + if (!dev_match) + return -1; + score += 4; if (sk->sk_incoming_cpu == raw_smp_processor_id()) score++; diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c index 1ede7a16a0be..4813293d4fad 100644 --- a/net/ipv6/datagram.c +++ b/net/ipv6/datagram.c @@ -782,7 +782,10 @@ int ip6_datagram_send_ctl(struct net *net, struct sock *sk, if (src_info->ipi6_ifindex) { if (fl6->flowi6_oif && - src_info->ipi6_ifindex != fl6->flowi6_oif) + src_info->ipi6_ifindex != fl6->flowi6_oif && + (sk->sk_bound_dev_if != fl6->flowi6_oif || + !sk_dev_equal_l3scope( + sk, src_info->ipi6_ifindex))) return -EINVAL; fl6->flowi6_oif = src_info->ipi6_ifindex; } diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 83f4c77c79d8..6722490c87b9 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -117,6 +117,7 @@ static int compute_score(struct sock *sk, struct net *net, { int score; struct inet_sock *inet; + bool dev_match; if (!net_eq(sock_net(sk), net) || udp_sk(sk)->udp_port_hash != hnum || @@ -144,15 +145,10 @@ static int compute_score(struct sock *sk, struct net *net, score++; } - if (sk->sk_bound_dev_if || exact_dif) { - bool dev_match = (sk->sk_bound_dev_if == dif || - sk->sk_bound_dev_if == sdif); - - if (!dev_match) - return -1; - if (sk->sk_bound_dev_if) - score++; - } + dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif); + if (!dev_match) + return -1; + score++; if (sk->sk_incoming_cpu == raw_smp_processor_id()) score++; -- 2.11.0