Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756566AbZDPQ3g (ORCPT ); Thu, 16 Apr 2009 12:29:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753601AbZDPQ30 (ORCPT ); Thu, 16 Apr 2009 12:29:26 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:47312 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752302AbZDPQ3Z (ORCPT ); Thu, 16 Apr 2009 12:29:25 -0400 Date: Thu, 16 Apr 2009 11:29:10 -0500 From: "Serge E. Hallyn" To: Alexey Dobriyan Cc: Oren Laadan , Dave Hansen , xemul@parallels.com, containers@lists.linux-foundation.org, mingo@elte.hu, linux-kernel@vger.kernel.org, hch@infradead.org, akpm@linux-foundation.org, torvalds@linux-foundation.org Subject: Re: CAP_SYS_ADMIN on restart(2) Message-ID: <20090416162910.GA20736@us.ibm.com> References: <20090414145830.GA27461@x200.localdomain> <49E4D115.5080601@cs.columbia.edu> <20090414204912.GA28458@x200.localdomain> <20090414213934.GB17986@us.ibm.com> <20090415192150.GC26994@x200.localdomain> <1239827033.32604.167.camel@nimitz> <20090415203920.GA5475@us.ibm.com> <49E64BFF.5080002@cs.columbia.edu> <20090415211609.GA6704@us.ibm.com> <20090416153513.GA7876@x200.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090416153513.GA7876@x200.localdomain> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1004 Lines: 21 Quoting Alexey Dobriyan (adobriyan@gmail.com): > > What Alexey wants, I believe, is for users to be able to not have > > to worry about there being exploitable bugs in restart(2) which > > unprivileged users can play with. And for the usual distro-kernel > > reasons, saying use 'CONFIG_CHECKPOINT=n' is not an option. > > This is correct, yes. If I would be a sysadmin who knows a bit about > kernel internals, I'd never trust restart(2) to get it right. Now I suppose what we could do is define a new CAP_SYS_RESTART capability and require that. Then the admin to whom I'm trying to cater could simply 'capset cap_sys_restart=pe /bin/restart'. Then all users could use restart without being granted the extra privilege implied by CAP_SYS_ADMIN. -serge -- 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/