Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 4 Oct 2001 08:54:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 4 Oct 2001 08:53:58 -0400 Received: from gannet.scg.man.ac.uk ([130.88.94.110]:24337 "EHLO gannet.scg.man.ac.uk") by vger.kernel.org with ESMTP id ; Thu, 4 Oct 2001 08:53:46 -0400 Date: Thu, 4 Oct 2001 13:54:12 +0100 From: John Levon To: linux-kernel@vger.kernel.org Subject: Re: Security question: "Text file busy" overwriting executables but not shared libraries? Message-ID: <20011004135412.A22854@compsoc.man.ac.uk> In-Reply-To: <200110031249.HAA50103@tomcat.admin.navo.hpc.mil> <01100319203903.00728@localhost.localdomain> <9pgsk4$7ep$1@penguin.transmeta.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9pgsk4$7ep$1@penguin.transmeta.com> User-Agent: Mutt/1.3.19i X-Url: http://www.movement.uklinux.net/ X-Record: Truant - Neither Work Nor Leisure X-Toppers: N/A Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 04, 2001 at 05:38:12AM +0000, Linus Torvalds wrote: > The reason the kernel refuses to honour it, is that MAP_DENYWRITE is an > excellent DoS-vehicle - you just mmap("/etc/passwd") with MAP_DENYWRITE, > and even root cannot write to it.. Vary nasty. why is MAP_EXECUTABLE dealt with in the same way then ? john -- " It is quite humbling to realize that the storage occupied by the longest line from a typical Usenet posting is sufficient to provide a state space so vast that all the computation power in the world can not conquer it." - Dave Wallace - 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/