Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261756AbVD0Puv (ORCPT ); Wed, 27 Apr 2005 11:50:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261780AbVD0Puv (ORCPT ); Wed, 27 Apr 2005 11:50:51 -0400 Received: from gate.in-addr.de ([212.8.193.158]:26560 "EHLO mx.in-addr.de") by vger.kernel.org with ESMTP id S261756AbVD0Pud (ORCPT ); Wed, 27 Apr 2005 11:50:33 -0400 Date: Wed, 27 Apr 2005 17:50:22 +0200 From: Lars Marowsky-Bree To: Martin Mares , Miklos Szeredi Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] private mounts Message-ID: <20050427155022.GR4431@marowsky-bree.de> References: <20050426094727.GA30379@infradead.org> <20050426131943.GC2226@openzaurus.ucw.cz> <20050426201411.GA20109@elf.ucw.cz> <20050427092450.GB1819@elf.ucw.cz> <20050427143126.GB1957@mail.shareable.org> <20050427153320.GA19065@atrey.karlin.mff.cuni.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20050427153320.GA19065@atrey.karlin.mff.cuni.cz> X-Ctuhulu: HASTUR User-Agent: Mutt/1.5.6i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1475 Lines: 36 On 2005-04-27T17:33:20, Martin Mares wrote: > > It is not there for the purpose of protecting user's data. Rather for > > protecting other users (including root) from unknowingly entering the > > FUSE directory and thus leaking otherwise inaccessible information > > (exact file operations performed) to the mount owner. > > Huh? Do you really suppose that there could be anything secret in the > operations somebody else is performing on your files? It is certainly an information leak not otherwise available. And with the ability to change the layout underneath, you might trigger bugs in root programs: Are they really capable of seeing the same filename twice, or can you throw them into a deep recursion by simulating infinitely deep directories/circular hardlinks...? Certainly a useful tool for hardening applications, but I can see the point of not wanting to let unwary applications run into a namespace controlled by a user. Of course, this is sort-of similar to "find -xdev", but I'm not sure whether it is not indeed new behaviour. Sincerely, Lars Marowsky-Br?e -- High Availability & Clustering SUSE Labs, Research and Development SUSE LINUX Products GmbH - A Novell Business - 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/