diff options
author | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-12-30 22:41:46 +0100 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2018-01-08 18:11:04 +0100 |
commit | a7f87b47e67e4341f6175cdb80e5c2eaadf30dcb (patch) | |
tree | 47f8be7118f28a8d3f4920968c96d3cb596d7ef2 /net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c | |
parent | f6931f5f5b713705c3cc91e4f9c222f2b181e2ef (diff) |
netfilter: remove defensive check on malformed packets from raw sockets
Users cannot forge malformed IPv4/IPv6 headers via raw sockets that they
can inject into the stack. Specifically, not for IPv4 since 55888dfb6ba7
("AF_RAW: Augment raw_send_hdrinc to expand skb to fit iphdr->ihl
(v2)"). IPv6 raw sockets also ensure that packets have a well-formed
IPv6 header available in the skbuff.
At quick glance, br_netfilter also validates layer 3 headers and it
drops malformed both IPv4 and IPv6 packets.
Therefore, let's remove this defensive check all over the place.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c')
-rw-r--r-- | net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c | 5 |
1 files changed, 0 insertions, 5 deletions
diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c index bb2c868a5621..de213a397ea8 100644 --- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c +++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c @@ -154,11 +154,6 @@ static unsigned int ipv4_conntrack_local(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) { - /* root is playing with raw sockets. */ - if (skb->len < sizeof(struct iphdr) || - ip_hdrlen(skb) < sizeof(struct iphdr)) - return NF_ACCEPT; - if (ip_is_fragment(ip_hdr(skb))) /* IP_NODEFRAG setsockopt set */ return NF_ACCEPT; |