netdev - Re: Possible DoS with 6RD border relay

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: <201201041135.54071.bcook@breakingpoint.com>
Date:	Wed, 4 Jan 2012 11:35:54 -0600
From:	Brent Cook <bcook@...akingpoint.com>
To:	Eric Dumazet <eric.dumazet@...il.com>
CC:	<netdev@...r.kernel.org>
Subject: Re: Possible DoS with 6RD border relay

On Wednesday, January 04, 2012 11:25:31 AM Eric Dumazet wrote:
> Le mercredi 04 janvier 2012 à 11:02 -0600, Brent Cook a écrit :
> > I forgot to mention, I'm testing 3.2 rc7:
> > 
> > Linux target1 3.2.0-7-generic #13-Ubuntu SMP Sat Dec 24 18:06:57 UTC 2011
> > x86_64 x86_64 x86_64 GNU/Linux
> > 
> > but the same behavior occurs with 2.6.35
> 
> Please check :
> 
> grep . /proc/sys/net/ipv6/route/*

/proc/sys/net/ipv6/route/gc_elasticity:9
/proc/sys/net/ipv6/route/gc_interval:30
/proc/sys/net/ipv6/route/gc_min_interval:0
/proc/sys/net/ipv6/route/gc_min_interval_ms:500
/proc/sys/net/ipv6/route/gc_thresh:1024
/proc/sys/net/ipv6/route/gc_timeout:60
/proc/sys/net/ipv6/route/max_size:4096
/proc/sys/net/ipv6/route/min_adv_mss:1220
/proc/sys/net/ipv6/route/mtu_expires:600

This is a system with 8GB of ram.

If I modify gc_thresh to be >= the number of bits the client varies, the 
system works OK:

/proc/sys/net/ipv6/neigh/default/gc_thresh1:128
/proc/sys/net/ipv6/neigh/default/gc_thresh2:512
/proc/sys/net/ipv6/neigh/default/gc_thresh3:1024

root@...get1:~# echo 200000 > /proc/sys/net/ipv6/neigh/default/gc_thresh1
root@...get1:~# echo 200000 > /proc/sys/net/ipv6/neigh/default/gc_thresh2
root@...get1:~# echo 200000 > /proc/sys/net/ipv6/neigh/default/gc_thresh3

But it seems to be a losing battle since the client has a delegated prefix of 
/64.
--
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