Subject: Old problem?
To: None <tech-security@netbsd.org>
From: Tomasz Marciniak <whistler@hoth.amu.edu.pl>
List: tech-security
Date: 06/29/2002 13:27:01
How do I protect my system against that simple DoS:
http://felix.fizyka.amu.edu.pl/~tm/dos.c
It hangs NetBSD 1.6A, NetBSD 1.6BETA3 (both Pentium III with
256M RAM) in about 10 sec.
In /var/log/messages:
Jun 26 19:20:08 felix /netbsd: WARNING: mclpool limit reached; increase NMBCLUSTERS
The kernel was compiled with:
options NMBCLUSTERS=4096
The login class definition of a user who runs the
evil code is:
someclass:\
:cputime=16:\
:datasize-cur=22M:\
:stacksize-cur=8M:\
:memorylocked-cur=10M:\
:memoryuse-cur=10M:\
:filesize=infinity:\
:coredumpsize=infinity:\
:maxproc-cur=32:\
:openfiles-cur=32:\
:sbsize=1048576:\
:priority=0:\
:umask=022:
The solution suggested in:
http://www.securitybugware.org/BSD/131.html
does not help.
--
Tomasz Marciniak