Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754230AbXIYN7I (ORCPT ); Tue, 25 Sep 2007 09:59:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751430AbXIYN64 (ORCPT ); Tue, 25 Sep 2007 09:58:56 -0400 Received: from hawking.rebel.net.au ([203.20.69.83]:34238 "EHLO hawking.rebel.net.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751407AbXIYN6z (ORCPT ); Tue, 25 Sep 2007 09:58:55 -0400 Message-ID: <46F91417.9050600@davidnewall.com> Date: Tue, 25 Sep 2007 23:28:47 +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: <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> <46F83474.5040503@davidnewall.com> <20070924230008.GA3160@vino.hallyn.com> <46F8BC8A.7080006@davidnewall.com> <20070925114947.GA9721@vino.hallyn.com> In-Reply-To: <20070925114947.GA9721@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: 1282 Lines: 40 Serge E. Hallyn wrote: > Quoting David Newall (david@davidnewall.com): > >> Serge E. Hallyn wrote: >> >>> Quoting David Newall (david@davidnewall.com): >>> >>> >>>> 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. >>>> >>>> >>> It can. >>> >>> Please re-read my previous msg. >>> >> I read it. Currently pivot_root can't be used to affect a single process. >> > > No. If you unshare your mounts namespace immediately before pivot_root, > then pivot_root will only affect that single process. > Bugger. You're right, I didn't read your previous message; I thought I had but I was wrong. >> unshare(CLONE_NEWNS); >> chdir(new_dir); >> pivot_root(new_dir, oldroot); After further RTFMing, and assuming "any processes or threads which use the old root directory" means what you imply, and surely it does, then I agree: pivot_root already does the job. Does anybody still need to use a bug in chroot? - 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/