Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262135AbVAYU6K (ORCPT ); Tue, 25 Jan 2005 15:58:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262132AbVAYUzy (ORCPT ); Tue, 25 Jan 2005 15:55:54 -0500 Received: from turing-police.cc.vt.edu ([128.173.14.107]:36107 "EHLO turing-police.cc.vt.edu") by vger.kernel.org with ESMTP id S262117AbVAYUyd (ORCPT ); Tue, 25 Jan 2005 15:54:33 -0500 Message-Id: <200501252053.j0PKr3G4022890@turing-police.cc.vt.edu> X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.1-RC3 To: John Richard Moser Cc: dtor_core@ameritech.net, Linus Torvalds , Bill Davidsen , Arjan van de Ven , Ingo Molnar , Christoph Hellwig , Dave Jones , Andrew Morton , marcelo.tosatti@cyclades.com, Greg KH , chrisw@osdl.org, Alan Cox , Kernel Mailing List Subject: Re: thoughts on kernel security issues In-Reply-To: Your message of "Tue, 25 Jan 2005 14:56:13 EST." <41F6A45D.1000804@comcast.net> From: Valdis.Kletnieks@vt.edu References: <1106157152.6310.171.camel@laptopd505.fenrus.org> <200501191947.j0JJlf3j024206@turing-police.cc.vt.edu> <41F6604B.4090905@tmr.com> <41F6816D.1020306@tmr.com> <41F68975.8010405@comcast.net> <41F691D6.8040803@comcast.net> <41F6A45D.1000804@comcast.net> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1106686383_3966P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Tue, 25 Jan 2005 15:53:03 -0500 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1558 Lines: 43 --==_Exmh_1106686383_3966P Content-Type: text/plain; charset=us-ascii On Tue, 25 Jan 2005 14:56:13 EST, John Richard Moser said: > This puts pressure on the attacker; he has to find a bug, write an > exploit, and find an opportunity to use it before a patch is written and > applied to fix the exploit. If say 80% of exploits are suddenly > non-exploitable, then he's left with mostly very short windows that are > far and few, and thus may be beyond his level of UNION(task->skill, > task->luck) in many cases. Correct. > If you can circumvent protection A by simply using attack B* to disable > protection A to do more interesting attack A*, then protection A is > smoke and mirrors. You however missed an important case here. If attack B is outside UNTION(task->skill, task->luck) protection A is *NOT* smoke-and-mirrors. And for the *vast* majority of attackers, if they have a canned exploit for A and it doesn't work, they'll be stuck because B is outside their ability. --==_Exmh_1106686383_3966P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.6 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQFB9rGvcC3lWbTT17ARAkkKAKCUOiUBcuk97bnhKopkS7BlRz947gCgor5l 8TwYtwhumkigdu85g9xG6/o= =oI50 -----END PGP SIGNATURE----- --==_Exmh_1106686383_3966P-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/