This is a note to let you know that I've just added the patch titled netfilter: use skb_to_full_sk in ip_route_me_harder to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: netfilter-use-skb_to_full_sk-in-ip_route_me_harder.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 29e09229d9f26129a39462fae0ddabc4d9533989 Mon Sep 17 00:00:00 2001 From: Florian Westphal <fw@xxxxxxxxx> Date: Fri, 17 Feb 2017 08:39:28 +0100 Subject: netfilter: use skb_to_full_sk in ip_route_me_harder From: Florian Westphal <fw@xxxxxxxxx> commit 29e09229d9f26129a39462fae0ddabc4d9533989 upstream. inet_sk(skb->sk) is illegal in case skb is attached to request socket. Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead of listener") Reported by: Daniel J Blueman <daniel@xxxxxxxxx> Signed-off-by: Florian Westphal <fw@xxxxxxxxx> Tested-by: Daniel J Blueman <daniel@xxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/netfilter.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/net/ipv4/netfilter.c +++ b/net/ipv4/netfilter.c @@ -23,7 +23,8 @@ int ip_route_me_harder(struct net *net, struct rtable *rt; struct flowi4 fl4 = {}; __be32 saddr = iph->saddr; - __u8 flags = skb->sk ? inet_sk_flowi_flags(skb->sk) : 0; + const struct sock *sk = skb_to_full_sk(skb); + __u8 flags = sk ? inet_sk_flowi_flags(sk) : 0; unsigned int hh_len; if (addr_type == RTN_UNSPEC) @@ -39,7 +40,7 @@ int ip_route_me_harder(struct net *net, fl4.daddr = iph->daddr; fl4.saddr = saddr; fl4.flowi4_tos = RT_TOS(iph->tos); - fl4.flowi4_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0; + fl4.flowi4_oif = sk ? sk->sk_bound_dev_if : 0; fl4.flowi4_mark = skb->mark; fl4.flowi4_flags = flags; rt = ip_route_output_key(net, &fl4); @@ -58,7 +59,7 @@ int ip_route_me_harder(struct net *net, xfrm_decode_session(skb, flowi4_to_flowi(&fl4), AF_INET) == 0) { struct dst_entry *dst = skb_dst(skb); skb_dst_set(skb, NULL); - dst = xfrm_lookup(net, dst, flowi4_to_flowi(&fl4), skb->sk, 0); + dst = xfrm_lookup(net, dst, flowi4_to_flowi(&fl4), sk, 0); if (IS_ERR(dst)) return PTR_ERR(dst); skb_dst_set(skb, dst); Patches currently in stable-queue which might be from fw@xxxxxxxxx are queue-4.4/netfilter-add-back-stackpointer-size-checks.patch queue-4.4/netfilter-use-skb_to_full_sk-in-ip_route_me_harder.patch queue-4.4/netfilter-ipv6-fix-use-after-free-write-in-nf_nat_ipv6_manip_pkt.patch queue-4.4/netfilter-ebtables-config_compat-don-t-trust-userland-offsets.patch queue-4.4/netfilter-nfnetlink_queue-fix-timestamp-attribute.patch queue-4.4/netfilter-bridge-ebt_among-add-missing-match-size-checks.patch