Re: Fork Bombing Attack

[Krzysztof Halasa]

"Anand Jahagirdar" <anandjigar@xxxxxxxxx> writes:

> ulimit are by default  set to some value for all users.. root, guest.
> on my machine with FC4 distribution when i typed command "ulimit -u"
> it gave me output as 3055 and another machine having FC6 distribution
> output is 8050. when root or any other user changes ulimit by typing
> "ulimit -u value",.ulimit value is changed for that session and not
> permantely. actually ulimit should help to prevent fork bombing attack
> but it wont and fork bombing attack still take down the machine having
> latest linux distributions.

how about:
$ ulimit -u 100
$ for f in `seq 1 500`; do (sleep 100&); done

(on another terminal)
$ ps xa|grep 'sleep 100' |wc -l

mine prints 93.
-- 
Krzysztof Halasa
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