From 802169a4b0f71d25a0f798a9c0657a565b1e79bc Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Thu, 10 May 2007 14:17:36 -0700 Subject: [PATCH] [NETFILTER]: iptable_raw: ignore short packets sent by SOCK_RAW sockets iptables matches and targets expect packets to have at least a full IP header and a valid header length. Ignore packets sent through raw sockets for which this isn't true as in the other tables. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/ipv4/netfilter/iptable_raw.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/net/ipv4/netfilter/iptable_raw.c b/net/ipv4/netfilter/iptable_raw.c index f7d28fd748e2..d6e503395684 100644 --- a/net/ipv4/netfilter/iptable_raw.c +++ b/net/ipv4/netfilter/iptable_raw.c @@ -5,6 +5,7 @@ */ #include #include +#include #define RAW_VALID_HOOKS ((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_LOCAL_OUT)) @@ -54,6 +55,24 @@ ipt_hook(unsigned int hook, return ipt_do_table(pskb, hook, in, out, &packet_raw); } +static unsigned int +ipt_local_hook(unsigned int hook, + struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + /* root is playing with raw sockets. */ + if ((*pskb)->len < sizeof(struct iphdr) || + ip_hdrlen(*pskb) < sizeof(struct iphdr)) { + if (net_ratelimit()) + printk("iptable_raw: ignoring short SOCK_RAW" + "packet.\n"); + return NF_ACCEPT; + } + return ipt_do_table(pskb, hook, in, out, &packet_raw); +} + /* 'raw' is the very first table. */ static struct nf_hook_ops ipt_ops[] = { { @@ -64,7 +83,7 @@ static struct nf_hook_ops ipt_ops[] = { .owner = THIS_MODULE, }, { - .hook = ipt_hook, + .hook = ipt_local_hook, .pf = PF_INET, .hooknum = NF_IP_LOCAL_OUT, .priority = NF_IP_PRI_RAW, -- 2.20.1