Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760322AbXIXWEv (ORCPT ); Mon, 24 Sep 2007 18:04:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756101AbXIXWEl (ORCPT ); Mon, 24 Sep 2007 18:04:41 -0400 Received: from hawking.rebel.net.au ([203.20.69.83]:34186 "EHLO hawking.rebel.net.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755737AbXIXWEk (ORCPT ); Mon, 24 Sep 2007 18:04:40 -0400 Message-ID: <46F83474.5040503@davidnewall.com> Date: Tue, 25 Sep 2007 07:34:36 +0930 From: David Newall User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.2) Gecko/20070221 SeaMonkey/1.1.1 MIME-Version: 1.0 To: "Serge E. Hallyn" CC: Bill Davidsen , Philipp Marek , 7eggert@gmx.de, Alan Cox , majkls , bunk@fs.tum.de, linux-kernel@vger.kernel.org Subject: Re: sys_chroot+sys_fchdir Fix References: <952DN-83o-31@gated-at.bofh.it> <56705.193.171.152.61.1190289559.squirrel@webmail.marek.priv.at> <46F29A9A.4070806@davidnewall.com> <200709201817.17282@x5> <46F2B59F.8090709@davidnewall.com> <46F2DDD0.3030500@tmr.com> <46F380E4.4040606@davidnewall.com> <20070924213215.GA32716@vino.hallyn.com> In-Reply-To: <20070924213215.GA32716@vino.hallyn.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 938 Lines: 23 Serge E. Hallyn wrote: > No reason for any new parameters to pivot_root. Just clone your mounts > namespace first. > > unshare(CLONE_NEWNS); > chdir(new_dir); > pivot_root(new_dir, oldroot); > > Since pivot_root actually fiddles with the vfsmnts, this is really the > only way to go about having it "work with just one process". I think the point is that, whereas we'd like to be able to pivot the root for a single process, in practice this causes startup issues to which the easy solution is to pivot the whole system. At least that's my reading of the man page. It might be tidy if pivot_root could be used (instead of a hack based on a chroot bug), but it'd still be unportable. - 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/