From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <10011d262a8868a1773f7b7f7b9c9d57@csplan9.rit.edu>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Google search of the day
Date: Thu, 14 Feb 2008 12:09:03 -0500
From: john@csplan9.rit.edu
In-Reply-To: <47B46ECD.D08BED0F@null.net>
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> john@csplan9.rit.edu wrote:
>>         for (;;)
>>                 fork();
>
> In genuine UNIX(tm) systems, there is a per-user process limit,
> so eventually the fork requests start failing.  However, this
> program keeps trying to fork, so if you kill off some of the
> child processes it will spawn replacements.
>
> I don't think it counts as a proper "denial of service" attack,
> since it affects only the invoking user (well, it does bog
> down the system with swapping etc. but again, per-user resource
> bounds can address that).

It's a proper denial of service on Plan 9... I ran it while
cpu'd into another box and found that somehow it killed *both*
machines. IIRC, Plan 9 doesn't really have any kind of resource
limiting, does it? (Yeah, I know, not necessary for a terminal,
but it should be important for a cpu server)


John