Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964850AbWAZU2B (ORCPT ); Thu, 26 Jan 2006 15:28:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932388AbWAZU2A (ORCPT ); Thu, 26 Jan 2006 15:28:00 -0500 Received: from MAIL.13thfloor.at ([212.16.62.50]:24458 "EHLO mail.13thfloor.at") by vger.kernel.org with ESMTP id S932242AbWAZU2A (ORCPT ); Thu, 26 Jan 2006 15:28:00 -0500 Date: Thu, 26 Jan 2006 21:27:59 +0100 From: Herbert Poetzl To: "Eric W. Biederman" Cc: "Serge E. Hallyn" , linux-kernel@vger.kernel.org, "Alan Cox Dave Hansen" , Arjan van de Ven , Suleiman Souhlal , Hubertus Franke , Cedric Le Goater Subject: Re: RFC: Multiple instances of kernel namespaces. Message-ID: <20060126202758.GD20473@MAIL.13thfloor.at> Mail-Followup-To: "Eric W. Biederman" , "Serge E. Hallyn" , linux-kernel@vger.kernel.org, "Alan Cox Dave Hansen" , Arjan van de Ven , Suleiman Souhlal , Hubertus Franke , Cedric Le Goater References: <1137522550.14135.76.camel@localhost.localdomain> <1137610912.24321.50.camel@localhost.localdomain> <1137612537.3005.116.camel@laptopd505.fenrus.org> <1137613088.24321.60.camel@localhost.localdomain> <1137624867.1760.1.camel@localhost.localdomain> <20060120201353.GA13265@sergelap.austin.ibm.com> <20060126194755.GA20473@MAIL.13thfloor.at> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.6i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1860 Lines: 46 On Thu, Jan 26, 2006 at 01:13:45PM -0700, Eric W. Biederman wrote: > Herbert Poetzl writes: > > > On Sat, Jan 21, 2006 at 03:04:16AM -0700, Eric W. Biederman wrote: > >> So in the simple case I have names like: > >> 1178/1632 > > > > which is a new namespace in itself, but it doesn't matter > > as long as it uniquely and persistently identifies the > > namespace for the time it exists ... just leaves the > > question how to retrieve a list of all namespaces :) > > Yes but the name of the namespace is still in the original pid namespace. > And more importantly to me it isn't a new kind of namespace. > > >> If I want a guest that can keep secrets from the host sysadmin I don't > >> want transitioning into a guest namespace to come too easily. > > > > which can easily be achieved by 'marking' the namespace > > as private and/or applying certain rules/checks to the > > 'enter' procedure ... > > Right. The trick here is that you must be able to deny > transitioning into a namespace from the inside the namespace. > Or else a guest could never trust it. Something one of my > coworkers pointed out to me. not necessarily, for example have a 'private' flag, which can only be set once (usually from outside), ensuring that the namespace will not be entered. this flag could be checked from inside ... best, Herbert > Eric > - > 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/ - 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/