Re: Local DoS in FreeBSD

[jeff () CETLINK NET (Jeff Wheat)]

On 01-Sep-99 Darren Reed wrote:
> > This was first posted to the FreeBSD security list on the 9th of August,
> > subsequently discussed on freebsd-stable and freebsd-hackers... no one
> > seems to care, even though it is able to lock up 2.2.6, 2.2.8, and 3.2.x
> > machines consistantly. I have also been told that it affects NetBSD and
> > OpenBSD, though I haven't confirmed it.
> >
> > Someone with the know-how care to fix?
>
> Fixing this has been discussed internally, I imagine, by many of the
> affected OS's.  The problem is a resource stavation issue - in this
> case mbuf's.  Arguably, it shouldn't "lock up", just freeze up anything
> that does networking.
>
> I imagine you could lock up more than just the *BSD's with this program.
>
> Darren

In all the tests that I have conducted on my FreeBSD systems, both
intel and alpha based, versions 2.2.2 through 4.0-19990809-CURRENT
result in the machines rebooting after running this DoS. The only
work-around for this is supposedly setting resource limits in the
/etc/login.conf file or to prevent public access to the machines.

Regards,
Jeff