From b078556aecd791b0e5cb3a59f4c3a14273b52121 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 19 Feb 2018 08:10:17 +0100 Subject: netfilter: ipv6: fix use-after-free Write in nf_nat_ipv6_manip_pkt l4proto->manip_pkt() can cause reallocation of skb head so pointer to the ipv6 header must be reloaded. Reported-and-tested-by: Fixes: 58a317f1061c89 ("netfilter: ipv6: add IPv6 NAT support") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/ipv6/netfilter/nf_nat_l3proto_ipv6.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net/ipv6') diff --git a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c index bed57ee65f7b..6b7f075f811f 100644 --- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c +++ b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c @@ -99,6 +99,10 @@ static bool nf_nat_ipv6_manip_pkt(struct sk_buff *skb, !l4proto->manip_pkt(skb, &nf_nat_l3proto_ipv6, iphdroff, hdroff, target, maniptype)) return false; + + /* must reload, offset might have changed */ + ipv6h = (void *)skb->data + iphdroff; + manip_addr: if (maniptype == NF_NAT_MANIP_SRC) ipv6h->saddr = target->src.u3.in6; -- cgit v1.2.3 From 47b7e7f82802dced3ac73658bf4b77584a63063f Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 15 Feb 2018 00:23:05 +0100 Subject: netfilter: don't set F_IFACE on ipv6 fib lookups "fib" starts to behave strangely when an ipv6 default route is added - the FIB lookup returns a route using 'oif' in this case. This behaviour was inherited from ip6tables rpfilter so change this as well. Bugzilla: https://bugzilla.netfilter.org/show_bug.cgi?id=1221 Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/ipv6/netfilter/ip6t_rpfilter.c | 4 ---- net/ipv6/netfilter/nft_fib_ipv6.c | 12 ++---------- 2 files changed, 2 insertions(+), 14 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/netfilter/ip6t_rpfilter.c b/net/ipv6/netfilter/ip6t_rpfilter.c index 94deb69bbbda..91ed25a24b79 100644 --- a/net/ipv6/netfilter/ip6t_rpfilter.c +++ b/net/ipv6/netfilter/ip6t_rpfilter.c @@ -48,10 +48,6 @@ static bool rpfilter_lookup_reverse6(struct net *net, const struct sk_buff *skb, } fl6.flowi6_mark = flags & XT_RPFILTER_VALID_MARK ? skb->mark : 0; - if ((flags & XT_RPFILTER_LOOSE) == 0) { - fl6.flowi6_oif = dev->ifindex; - lookup_flags |= RT6_LOOKUP_F_IFACE; - } rt = (void *) ip6_route_lookup(net, &fl6, lookup_flags); if (rt->dst.error) diff --git a/net/ipv6/netfilter/nft_fib_ipv6.c b/net/ipv6/netfilter/nft_fib_ipv6.c index cc5174c7254c..62fc84d7bdff 100644 --- a/net/ipv6/netfilter/nft_fib_ipv6.c +++ b/net/ipv6/netfilter/nft_fib_ipv6.c @@ -180,7 +180,6 @@ void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs, } *dest = 0; - again: rt = (void *)ip6_route_lookup(nft_net(pkt), &fl6, lookup_flags); if (rt->dst.error) goto put_rt_err; @@ -189,15 +188,8 @@ void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs, if (rt->rt6i_flags & (RTF_REJECT | RTF_ANYCAST | RTF_LOCAL)) goto put_rt_err; - if (oif && oif != rt->rt6i_idev->dev) { - /* multipath route? Try again with F_IFACE */ - if ((lookup_flags & RT6_LOOKUP_F_IFACE) == 0) { - lookup_flags |= RT6_LOOKUP_F_IFACE; - fl6.flowi6_oif = oif->ifindex; - ip6_rt_put(rt); - goto again; - } - } + if (oif && oif != rt->rt6i_idev->dev) + goto put_rt_err; switch (priv->result) { case NFT_FIB_RESULT_OIF: -- cgit v1.2.3 From 7d98386d55a5afaa65de77e1e9197edeb8a42079 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 25 Feb 2018 11:49:07 -0800 Subject: netfilter: use skb_to_full_sk in ip6_route_me_harder MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit For some reason, Florian forgot to apply to ip6_route_me_harder the fix that went in commit 29e09229d9f2 ("netfilter: use skb_to_full_sk in ip_route_me_harder") Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead of listener")  Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: Pablo Neira Ayuso --- net/ipv6/netfilter.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c index d95ceca7ff8f..531d6957af36 100644 --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -21,18 +21,19 @@ int ip6_route_me_harder(struct net *net, struct sk_buff *skb) { const struct ipv6hdr *iph = ipv6_hdr(skb); + struct sock *sk = sk_to_full_sk(skb->sk); unsigned int hh_len; struct dst_entry *dst; struct flowi6 fl6 = { - .flowi6_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0, + .flowi6_oif = sk ? sk->sk_bound_dev_if : 0, .flowi6_mark = skb->mark, - .flowi6_uid = sock_net_uid(net, skb->sk), + .flowi6_uid = sock_net_uid(net, sk), .daddr = iph->daddr, .saddr = iph->saddr, }; int err; - dst = ip6_route_output(net, skb->sk, &fl6); + dst = ip6_route_output(net, sk, &fl6); err = dst->error; if (err) { IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); @@ -50,7 +51,7 @@ int ip6_route_me_harder(struct net *net, struct sk_buff *skb) if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) { skb_dst_set(skb, NULL); - dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), skb->sk, 0); + dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0); if (IS_ERR(dst)) return PTR_ERR(dst); skb_dst_set(skb, dst); -- cgit v1.2.3 From a6aa80446234ec0ad38eecdb8efc59e91daae565 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Tue, 27 Feb 2018 19:19:40 +0800 Subject: ip6_tunnel: fix IFLA_MTU ignored on NEWLINK Commit 128bb975dc3c ("ip6_gre: init dev->mtu and dev->hard_header_len correctly") fixed IFLA_MTU ignored on NEWLINK for ip6_gre. The same mtu fix is also needed for ip6_tunnel. Note that dev->hard_header_len setting for ip6_tunnel works fine, no need to fix it. Reported-by: Jianlin Shi Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/ipv6/ip6_tunnel.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index 4b15fe928278..6e0f21eed88a 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -1982,14 +1982,14 @@ static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, { struct net *net = dev_net(dev); struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); - struct ip6_tnl *nt, *t; struct ip_tunnel_encap ipencap; + struct ip6_tnl *nt, *t; + int err; nt = netdev_priv(dev); if (ip6_tnl_netlink_encap_parms(data, &ipencap)) { - int err = ip6_tnl_encap_setup(nt, &ipencap); - + err = ip6_tnl_encap_setup(nt, &ipencap); if (err < 0) return err; } @@ -2005,7 +2005,11 @@ static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, return -EEXIST; } - return ip6_tnl_create2(dev); + err = ip6_tnl_create2(dev); + if (!err && tb[IFLA_MTU]) + ip6_tnl_change_mtu(dev, nla_get_u32(tb[IFLA_MTU])); + + return err; } static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], -- cgit v1.2.3 From 2b3957c34b6d7f03544b12ebbf875eee430745db Mon Sep 17 00:00:00 2001 From: Xin Long Date: Tue, 27 Feb 2018 19:19:41 +0800 Subject: sit: fix IFLA_MTU ignored on NEWLINK Commit 128bb975dc3c ("ip6_gre: init dev->mtu and dev->hard_header_len correctly") fixed IFLA_MTU ignored on NEWLINK for ip6_gre. The same mtu fix is also needed for sit. Note that dev->hard_header_len setting for sit works fine, no need to fix it. sit is actually ipv4 tunnel, it can't call ip6_tnl_change_mtu to set mtu. Reported-by: Jianlin Shi Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/ipv6/sit.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'net/ipv6') diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 3a1775a62973..0195598f7bb5 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -1578,6 +1578,13 @@ static int ipip6_newlink(struct net *src_net, struct net_device *dev, if (err < 0) return err; + if (tb[IFLA_MTU]) { + u32 mtu = nla_get_u32(tb[IFLA_MTU]); + + if (mtu >= IPV6_MIN_MTU && mtu <= 0xFFF8 - dev->hard_header_len) + dev->mtu = mtu; + } + #ifdef CONFIG_IPV6_SIT_6RD if (ipip6_netlink_6rd_parms(data, &ip6rd)) err = ipip6_tunnel_update_6rd(nt, &ip6rd); -- cgit v1.2.3 From 779b7931b27bfa80bac46d0115d229259aef580b Mon Sep 17 00:00:00 2001 From: Daniel Axtens Date: Thu, 1 Mar 2018 17:13:37 +1100 Subject: net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len If you take a GSO skb, and split it into packets, will the network length (L3 headers + L4 headers + payload) of those packets be small enough to fit within a given MTU? skb_gso_validate_mtu gives you the answer to that question. However, we recently added to add a way to validate the MAC length of a split GSO skb (L2+L3+L4+payload), and the names get confusing, so rename skb_gso_validate_mtu to skb_gso_validate_network_len Signed-off-by: Daniel Axtens Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- net/ipv6/ip6_output.c | 2 +- net/ipv6/netfilter/nf_flow_table_ipv6.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 997c7f19ad62..a8a919520090 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -412,7 +412,7 @@ static bool ip6_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) if (skb->ignore_df) return false; - if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu)) + if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu)) return false; return true; diff --git a/net/ipv6/netfilter/nf_flow_table_ipv6.c b/net/ipv6/netfilter/nf_flow_table_ipv6.c index d346705d6ee6..207cb35569b1 100644 --- a/net/ipv6/netfilter/nf_flow_table_ipv6.c +++ b/net/ipv6/netfilter/nf_flow_table_ipv6.c @@ -178,7 +178,7 @@ static bool __nf_flow_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu) if (skb->len <= mtu) return false; - if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu)) + if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu)) return false; return true; -- cgit v1.2.3 From 80f5974d15ea96c7112604c7999a83a502d15b9f Mon Sep 17 00:00:00 2001 From: Daniel Axtens Date: Thu, 1 Mar 2018 17:13:39 +1100 Subject: net: xfrm: use skb_gso_validate_network_len() to check gso sizes Replace skb_gso_network_seglen() with skb_gso_validate_network_len(), as it considers the GSO_BY_FRAGS case. Signed-off-by: Daniel Axtens Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- net/ipv6/xfrm6_output.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv6') diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c index 8ae87d4ec5ff..5959ce9620eb 100644 --- a/net/ipv6/xfrm6_output.c +++ b/net/ipv6/xfrm6_output.c @@ -82,7 +82,7 @@ static int xfrm6_tunnel_check_size(struct sk_buff *skb) if ((!skb_is_gso(skb) && skb->len > mtu) || (skb_is_gso(skb) && - skb_gso_network_seglen(skb) > ip6_skb_dst_mtu(skb))) { + !skb_gso_validate_network_len(skb, ip6_skb_dst_mtu(skb)))) { skb->dev = dst->dev; skb->protocol = htons(ETH_P_IPV6); -- cgit v1.2.3