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From: "Chris Swiedler" <ceswiedler_lk@mindspring.com>
To: "Szabolcs Szakacsits" <szaka@f-secure.com>, <linux-kernel@vger.kernel.org>
Cc: "Erik Mouw" <J.A.K.Mouw@ITS.TUDelft.NL>
Subject: RE: [PATCH] Re: reliability of linux-vm subsystem
Date: Tue, 14 Nov 2000 10:24:21 -0500
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> > Good, so the OOM killer works.
>
> But it doesn't work for this kind of application misbehaviours (or
> user attacks):
>
> main() { while(1) if (fork()) malloc(1); }

This seems to be a fork() bomb, not a VM issue. The system is overwhelmed by
the the forks, not by the space consumed by the allocations themselves. For
one thing, I've found that

main() { while(1) malloc(1024*1024); }

does not kill your system very quickly (if at all). Without actually writing
to the memory, it doesn't seem to be "really" allocated. Adding a memset()
will kill your system much more quickly.

chris

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