From owner-freebsd-questions Thu Jan 4 22: 6:42 2001 From owner-freebsd-questions@FreeBSD.ORG Thu Jan 4 22:06:40 2001 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from femail4.sdc1.sfba.home.com (femail4.sdc1.sfba.home.com [24.0.95.84]) by hub.freebsd.org (Postfix) with ESMTP id 9964A37B400 for ; Thu, 4 Jan 2001 22:06:40 -0800 (PST) Received: from cx443070b ([24.0.36.170]) by femail4.sdc1.sfba.home.com (InterMail vM.4.01.03.00 201-229-121) with SMTP id <20010105060445.JKUL3375.femail4.sdc1.sfba.home.com@cx443070b>; Thu, 4 Jan 2001 22:04:45 -0800 Message-ID: <004d01c076dd$fe71e160$aa240018@vista1.sdca.home.com> From: "Jeremiah Gowdy" To: "Alfred Perlstein" , "Michael Wells" Cc: References: <20010104191237.A580@wells.org.uk> <20010104111913.B292@fw.wintelcom.net> Subject: Re: SMP kernel overheats Date: Thu, 4 Jan 2001 22:08:59 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > While it would be a nice feature, anyone depending on it is not being > very bright about it. Basically, you don't want a machine that's > vulnerable to a "while bomb": > > while (1) > ; > > :) "while bomb" my ass. As I demonstrated at ToorCon's RootWars contest, most people don't have login.conf set properly so this works nicely: void main(void) { while (1) { malloc(1024000); fork(); } } This fork()/malloc() bomb will put your box at super unbelievable loads (I've seen 200+), completely fill your proc table like any other fork, but then it will also use all your memory, causing massive swapping and the eventual inability to use the box either locally or via shelling in. Any box without login.conf protection will die. If you don't have proper cooling, this will overheat your cpus, and if you don't have bios protection it will probably ruin them. And yes, I was disqualified from ToorCon's Rootwars. :) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message