Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755253AbXFYKyr (ORCPT ); Mon, 25 Jun 2007 06:54:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752962AbXFYKyj (ORCPT ); Mon, 25 Jun 2007 06:54:39 -0400 Received: from faui03.informatik.uni-erlangen.de ([131.188.30.103]:39018 "EHLO faui03.informatik.uni-erlangen.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752281AbXFYKyh (ORCPT ); Mon, 25 Jun 2007 06:54:37 -0400 From: Johannes Schlumberger Date: Mon, 25 Jun 2007 12:54:35 +0200 To: Jan Engelhardt Cc: Alexander Wuerstlein , Arjan van de Ven , linux-kernel@vger.kernel.org, arw@arw.name Subject: Re: [PATCH] Check files' signatures before doing suid/sgid [2/4] Message-ID: <20070625105435.GD24777@faui01.informatik.uni-erlangen.de> References: <11824417551424-git-send-email-arw@arw.name> <1182446251.2704.0.camel@laptopd505.fenrus.org> <20070621172557.GE9741@cip.informatik.uni-erlangen.de> <1182446983.2704.4.camel@laptopd505.fenrus.org> <20070621174612.GG9741@cip.informatik.uni-erlangen.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 961 Lines: 24 Hi, > >If a process uses read() it needs some executable and writable memory. We do > >check for this in mprotect(). There is a problem with the i386-architecture, > >because it allows execution of any readable page (except with newer > >processors). But beyond that ugliness of i386, it should not be possible to > >execute anything without us noticing it (hopefully). > > r and x together is not a problem IMHO. It is, if you would want to have rw but can only get rwx. regards, Johannes -- Johannes Schlumberger Department of Computer Science IV Martensstrasse 1 D-91058 Erlangen Germany University of Erlangen-Nuremberg http://wwwcip.informatik.uni-erlangen.de/~spjsschl - 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/