linux.. securing it against rogue programs?

[Aravind Gottipati]

hi,
	I was on irc the other day and somone posted this one line
script/program

WARNING: YOU WILL PROBABLY END UP DOING A HARD REBOOT, IF YOU RUN THIS
SCRIPT FOR MORE THAN 10 SECONDS.

echo "main() { while (1) fork (); }" > p.c;cc p.c;./a.out

I knew what it would do.. fork processes forever and eventually eat up
all the memory. I still gave it a try because I wanted to see how my box
would react to it. I let it run for about 20 seconds and after that
nothing on my box would work anymore.. I ended up doing a hard reboot :(

A short little program like this could be written by any user that konws
a little C. It is scary to me that any one using a typical unix box can
run this and bring a whole box to a halt. How do I protect my boxes
against such mishaps? Are there programs/scripts that would protect
boxes against things like this or even better not let any processes use
100% of the memory just in case there are any suck problems.. While we
are it, I wouldn't mind it if you want to add other "WAYS TO BRING DOWN
A BOX EASILY" to this thread :).  Maybe we can make this a topic on one
of our demo days.. 

thank you,
Aravind
  
-- 
Don't look for the meaning of life! It may have no meaning, or, even 
worse, it may have a meaning of which you disapprove.
							-- Anonymous