On 14 Nov 2002, Jason Dixon wrote:

> Hi all:
>
> If this is a silly question, so be it.  ;-)
>
> Anyhoo, I'm stress-testing my new firewall in the lab, and I'm
> performing some igmp DoS attacks against it.  Running something like
> igmpofdeath (5000 packets) brings the system to a grinding halt (scrub
> on).
>
> (yes, I know DoS attacks are basically undefensible, but read on...)
>
> I tried setting a 5000 limit on the frags (scrub still on), and it was
> able to handle 5000, but choked on 10000.  I'm still relatively new to
> the concepts of stress-testing firewalls, so I'm not sure whether this
> kind of thing is something that needs to be reported as a "bug".
> Normally I wouldn't think so, but seeing as how the memory pool is
> supposedly being "capped", it makes me wonder.

This started out as a temporary solution. Isn't it time to solve the real
problem (the pool exhaustion bug)? Or is it impossible to fix this?


CVSROOT:        /cvs
Module name:    src
Changes by:     [EMAIL PROTECTED]        2002/02/26 00:25:33

Modified files:
        sys/net        : pfvar.h pf.c pf_norm.c
        sbin/pfctl     : pfctl.c pfctl.8

Log message:
Add optional pool memory hard limits, mainly as temporary solution
until pool exhaustion causes problems no more.


I think PR 2309 (pf crashes kernel when pool_get() exhausts memory)
is still open. So it's still possible to crash a firewall if you don't
have a state limit set. And apparantly it's possible to crash it even when
a fragment limit is set.


Cheers,

Dries
-- 
Dries Schellekens
email: [EMAIL PROTECTED]

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