netdev - Re: ipv4_get_l4proto: Frag of proto 17

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <46D8F87A.1080604@trash.net>
Date:	Sat, 01 Sep 2007 07:28:26 +0200
From:	Patrick McHardy <kaber@...sh.net>
To:	Meelis Roos <mroos@...ux.ee>
CC:	netdev@...r.kernel.org,
	Netfilter Development Mailinglist 
	<netfilter-devel@...ts.netfilter.org>
Subject: Re: ipv4_get_l4proto: Frag of proto 17

Meelis Roos wrote:
>>> Yesterdays git snapsot on a normal home PC spams dmesg with the following
>>> line:
>>> ipv4_get_l4proto: Frag of proto 17
>> In what situation does this happen?
> 
> It happens some times every hour on the average. Seems to be some UDP 
> traffic. Firewall allows in any UDP that is ESTABLISHEFD,RELATED, DHCP 
> (some more UDP rules with counter 0 so not important). Additionally 
> there is internal netowkr that sometimes has a laptop but usually not 
> and the messages have appeared also when there is nothin in the internal 
> network.
> 
> Locally mldonkey is probably using UDP, and lsof -i | grep UDP tells 
> that named, avahi-daemon, dhcpd, chronyd, nmbd and cupsd are listening 
> on UDP sockets (most of them on internal network).
> 
> But I have no idea what application is causing the messages.


I'm guessing that its ICMP errors containing UDP fragments.

Could you add a WARN_ON(1) to ipv4_get_l4proto() in
net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c to verify
this?

-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html