diff options
| author | Lin Zhang <xiaolou4617@gmail.com> | 2017-10-06 00:44:03 +0800 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-10-09 13:08:39 +0200 |
| commit | 49f817d793d1bcc11d721881aac037b996feef5c (patch) | |
| tree | f1525ecf75e8f4e4d7c9ffca73f2b097cb4c424a /net/ipv4/netfilter | |
| parent | e466af75c074e76107ae1cd5a2823e9c61894ffb (diff) | |
netfilter: SYNPROXY: skip non-tcp packet in {ipv4, ipv6}_synproxy_hook
In function {ipv4,ipv6}_synproxy_hook we expect a normal tcp packet, but
the real server maybe reply an icmp error packet related to the exist
tcp conntrack, so we will access wrong tcp data.
Fix it by checking for the protocol field and only process tcp traffic.
Signed-off-by: Lin Zhang <xiaolou4617@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/ipv4/netfilter')
| -rw-r--r-- | net/ipv4/netfilter/ipt_SYNPROXY.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv4/netfilter/ipt_SYNPROXY.c b/net/ipv4/netfilter/ipt_SYNPROXY.c index 811689e523c3..f75fc6b53115 100644 --- a/net/ipv4/netfilter/ipt_SYNPROXY.c +++ b/net/ipv4/netfilter/ipt_SYNPROXY.c @@ -330,7 +330,8 @@ static unsigned int ipv4_synproxy_hook(void *priv, if (synproxy == NULL) return NF_ACCEPT; - if (nf_is_loopback_packet(skb)) + if (nf_is_loopback_packet(skb) || + ip_hdr(skb)->protocol != IPPROTO_TCP) return NF_ACCEPT; thoff = ip_hdrlen(skb); |