The Unix Heritage Society mailing list
 help / color / mirror / Atom feed
From: bill@cs.uofs.edu (Bill Gunshannon)
Subject: [pups] User Mode DoS Attacks (was Re: Issues of AUUGN)
Date: Thu, 5 Oct 2006 10:33:19 -0400 (EDT)	[thread overview]
Message-ID: <4672.134.198.172.102.1160058799.squirrel@www.cs.scranton.edu> (raw)
In-Reply-To: <E183486F-6903-48DA-BBC2-D35A498B86A6@uwlax.edu>


>> But you'd need kernel mode for that; this is a DoS attack (one of the
>> first?) launched by a user.
>
> The userland DoS I remember:
>
> main() {
> 	while(1)
> 		fork();
> }

Typical "Rabbit Program".

>
> And in fact I tried it once on the 11/45 I had access to. Not pretty.
> It can be made less disastrous by judicious addition of a wait(); call.
>
> --Milo, wondering how contemporary UNIX will deal with such
> pathological behavior....

Not necessarily pathological.  I have students do it all the time
in the early parts of the Operating Systems Course.  The only one
it denies service to on contemorary UNIX is the individual who does
it.  Process limits are by user, not by system.

bill

-- 
Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three wolves
bill at cs.scranton.edu     |  and a sheep voting on what's for dinner.
University of Scranton   |
Scranton, Pennsylvania   |         #include <std.disclaimer.h>





  reply	other threads:[~2006-10-05 14:33 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <mailman.1.1160013601.40099.pups@minnie.tuhs.org>
2006-10-05 13:46 ` Milo Velimirovic
2006-10-05 14:33   ` Bill Gunshannon [this message]
2006-10-05 14:44     ` Johnny Billquist
2006-10-05 14:51   ` Tore Sinding Bekkedal

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4672.134.198.172.102.1160058799.squirrel@www.cs.scranton.edu \
    --to=bill@cs.uofs.edu \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).