Rusty Russell wrote:
On Monday 15 December 2008 06:33:53 Dave Jones wrote:
On Sun, Dec 14, 2008 at 06:09:17PM +0100, Jozsef Kadlecsik wrote:
> In a >normal< system one usually does not use raw sockets. So if a root
> process do use raw socket, at least netfilter sends a notification and
> there's a chance that someone take notice it by checking the kernel logs.
'normal' systems are irrelevant here. This message is triggerable remotely.
I don't think it can be. This is for truncated locally-generated outgoing
packets, which can only happen when root is playing with raw sockets.
Yes, it can only be triggered locally by root.
As you can probably tell, I was the one who wrote this printk :) IMHO,
one reasonable complaint is sufficient to have it removed, so just remove
it. If anyone thinks it's valuable, put a static counter < 5 around it
and add pid/comm info.
I've queued this patch to remove it.
commit ea1926cabd0076846119a7e10f29070907fc296c
Author: Patrick McHardy <kaber@xxxxxxxxx>
Date: Mon Jan 12 06:01:48 2009 +0100
netfilter: remove "happy cracking" message
Don't spam logs for locally generated short packets. these can only
be generated by root.
Signed-off-by: Patrick McHardy <kaber@xxxxxxxxx>
diff --git a/net/ipv4/netfilter/iptable_filter.c b/net/ipv4/netfilter/iptable_filter.c
index c922431..52cb693 100644
--- a/net/ipv4/netfilter/iptable_filter.c
+++ b/net/ipv4/netfilter/iptable_filter.c
@@ -93,13 +93,8 @@ ipt_local_out_hook(unsigned int hook,
{
/* root is playing with raw sockets. */
if (skb->len < sizeof(struct iphdr) ||
- ip_hdrlen(skb) < sizeof(struct iphdr)) {
- if (net_ratelimit())
- printk("iptable_filter: ignoring short SOCK_RAW "
- "packet.\n");
+ ip_hdrlen(skb) < sizeof(struct iphdr))
return NF_ACCEPT;
- }
-
return ipt_do_table(skb, hook, in, out,
dev_net(out)->ipv4.iptable_filter);
}
diff --git a/net/ipv4/netfilter/iptable_mangle.c b/net/ipv4/netfilter/iptable_mangle.c
index 69f2c42..3929d20 100644
--- a/net/ipv4/netfilter/iptable_mangle.c
+++ b/net/ipv4/netfilter/iptable_mangle.c
@@ -132,12 +132,8 @@ ipt_local_hook(unsigned int hook,
/* root is playing with raw sockets. */
if (skb->len < sizeof(struct iphdr)
- || ip_hdrlen(skb) < sizeof(struct iphdr)) {
- if (net_ratelimit())
- printk("iptable_mangle: ignoring short SOCK_RAW "
- "packet.\n");
+ || ip_hdrlen(skb) < sizeof(struct iphdr))
return NF_ACCEPT;
- }
/* Save things which could affect route */
mark = skb->mark;
diff --git a/net/ipv4/netfilter/iptable_raw.c b/net/ipv4/netfilter/iptable_raw.c
index 8faebfe..7f65d18 100644
--- a/net/ipv4/netfilter/iptable_raw.c
+++ b/net/ipv4/netfilter/iptable_raw.c
@@ -65,12 +65,8 @@ ipt_local_hook(unsigned int hook,
{
/* root is playing with raw sockets. */
if (skb->len < sizeof(struct iphdr) ||
- ip_hdrlen(skb) < sizeof(struct iphdr)) {
- if (net_ratelimit())
- printk("iptable_raw: ignoring short SOCK_RAW "
- "packet.\n");
+ ip_hdrlen(skb) < sizeof(struct iphdr))
return NF_ACCEPT;
- }
return ipt_do_table(skb, hook, in, out,
dev_net(out)->ipv4.iptable_raw);
}
diff --git a/net/ipv4/netfilter/iptable_security.c b/net/ipv4/netfilter/iptable_security.c
index 36f3be3..a52a35f 100644
--- a/net/ipv4/netfilter/iptable_security.c
+++ b/net/ipv4/netfilter/iptable_security.c
@@ -96,12 +96,8 @@ ipt_local_out_hook(unsigned int hook,
{
/* Somebody is playing with raw sockets. */
if (skb->len < sizeof(struct iphdr)
- || ip_hdrlen(skb) < sizeof(struct iphdr)) {
- if (net_ratelimit())
- printk(KERN_INFO "iptable_security: ignoring short "
- "SOCK_RAW packet.\n");
+ || ip_hdrlen(skb) < sizeof(struct iphdr))
return NF_ACCEPT;
- }
return ipt_do_table(skb, hook, in, out,
dev_net(out)->ipv4.iptable_security);
}
diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
index b2141e1..4beb04f 100644
--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
@@ -145,11 +145,8 @@ static unsigned int ipv4_conntrack_local(unsigned int hooknum,
{
/* root is playing with raw sockets. */
if (skb->len < sizeof(struct iphdr) ||
- ip_hdrlen(skb) < sizeof(struct iphdr)) {
- if (net_ratelimit())
- printk("ipt_hook: happy cracking.\n");
+ ip_hdrlen(skb) < sizeof(struct iphdr))
return NF_ACCEPT;
- }
return nf_conntrack_in(dev_net(out), PF_INET, hooknum, skb);
}
