Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932414AbXAIXOz (ORCPT ); Tue, 9 Jan 2007 18:14:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932482AbXAIXOz (ORCPT ); Tue, 9 Jan 2007 18:14:55 -0500 Received: from e36.co.us.ibm.com ([32.97.110.154]:38485 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932414AbXAIXOy (ORCPT ); Tue, 9 Jan 2007 18:14:54 -0500 Date: Tue, 9 Jan 2007 17:14:49 -0600 From: "Serge E. Hallyn" To: Christoph Hellwig , Arjan van de Ven , Mimi Zohar , akpm@osdl.org, kjhall@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, safford@watson.ibm.com, Pekka Enberg Subject: Re: mprotect abuse in slim Message-ID: <20070109231449.GA4547@sergelap.austin.ibm.com> References: <1168312045.3180.140.camel@laptopd505.fenrus.org> <20070109094625.GA11918@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070109094625.GA11918@infradead.org> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1832 Lines: 44 Quoting Christoph Hellwig (hch@infradead.org): > On Mon, Jan 08, 2007 at 07:07:25PM -0800, Arjan van de Ven wrote: > > > > > Starting with the fdtable, would it help if we move the > > > fdtable tweaking out of slim itself and into helpers? Or > > > can you recommend another way to implement this functionality. > > > > Hi, > > > > maybe this is a silly question, but do you revoke not only the current > > fd entries, but also the ones that are pending in UNIX domain sockets > > and that are already being sent to the process? If not.. then you might > > as well not bother ;) > > Exactly. What these folks want is revoke (maybe more fine grained, but > that's not the point). And guess what folks, revoke is not trivial, > otherwise we'd have it. If you want to volunteer to implement a full-blown > revoke that's fine, but > > a) it belongs into core code > b) needs to be done right Whatever happened with Pekka's revoke submissions? Did you lose interest after http://www.kernel.org/pub/linux/kernel/people/penberg/patches/revoke/2.6.19-rc1/revoke-2.6.19-rc1, or was it decided that the approach was unworkable? Now, what slim needs isn't "revoke all files for this inode", but "revoke this task's write access to this fd". So two functions which could be useful are int fd_revoke_write(struct task_struct *tsk, int fd) int fd_revoke_write_iter(struct task_struct *tsk, (int *)need_revoke(struct task_struct *tsk, int fd)) Anyway I'll get going on rebasing Pekka's latest patch (pending his reply) and providing the above two functions on top of that. -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/