Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754481AbXFDLH4 (ORCPT ); Mon, 4 Jun 2007 07:07:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753339AbXFDLHt (ORCPT ); Mon, 4 Jun 2007 07:07:49 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:34754 "EHLO amd.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753267AbXFDLHs (ORCPT ); Mon, 4 Jun 2007 07:07:48 -0400 Date: Mon, 4 Jun 2007 13:07:43 +0200 From: Pavel Machek To: david@lang.hm Cc: Valdis.Kletnieks@vt.edu, David Wagner , linux-kernel@vger.kernel.org Subject: Re: [AppArmor 01/41] Pass struct vfsmount to the inode_create LSM hook Message-ID: <20070604110743.GN4363@elf.ucw.cz> References: <653438.15244.qm@web36612.mail.mud.yahoo.com> <20070529144518.GD5840@ucw.cz> <20070529233041.GC24200@elf.ucw.cz> <20070524144726.GB3920@ucw.cz> <12508.1180719875@turing-police.cc.vt.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.11+cvs20060126 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1670 Lines: 39 On Fri 2007-06-01 11:00:50, david@lang.hm wrote: > On Fri, 1 Jun 2007, Valdis.Kletnieks@vt.edu wrote: > > >On Thu, 24 May 2007 14:47:27 -0000, Pavel Machek said: > >>Yes, if there's significantly more remote bad guys than local bad > >>guys, and if remote bad guys can't just get some local user first, AA > >>still has some value. > > > >Experience over on the Windows side of the fence indicates that "remote bad > >guys get some local user first" is a *MAJOR* part of the current real-world > >threat model - the vast majority of successful attacks on end-user boxes > >these > >days start off with either "Get user to (click on link|open attachment)" or > >"Subvert the path to a website (either by hacking the real site or > >hijacking > >the DNS) and deliver a drive-by fruiting when the user visits the page". > > and if your local non-root user can create a hard link to /etc/shadow and > access it they own your box anyway (they can just set the root password to > anything they want). I think you need to look how unix security works: pavel@amd:/tmp$ ln /etc/shadow . pavel@amd:/tmp$ cat shadow cat: shadow: Permission denied pavel@amd:/tmp$ Yes, regular users are permitted to hardlink shadow, no, it is not a security hole, yes, it is a problem for AA. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html - 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/