From mboxrd@z Thu Jan 1 00:00:00 1970 From: Al Boldi Subject: Re: [patch 1/2] [RFC] Simple tamper-proof device filesystem. Date: Mon, 17 Dec 2007 16:05:31 +0300 Message-ID: <200712171605.31084.a1426z@gawab.com> References: <47650A4C.4000708@davidnewall.com> <200712170040.lBH0e6sf099887@www262.sakura.ne.jp> <54137.81.207.0.53.1197891890.squirrel@secure.samage.net> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: david@davidnewall.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: "Indan Zupancic" , "Tetsuo Handa" Return-path: In-Reply-To: <54137.81.207.0.53.1197891890.squirrel@secure.samage.net> Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Indan Zupancic wrote: > On Mon, December 17, 2007 01:40, Tetsuo Handa wrote: > > So, use of this filesystem alone is meaningless because > > attackers with root privileges can do what you are saying. > > But use of this filesystem with MAC is still valid because > > MAC can prevent attackers with root privileges from doing what you are > > saying. > > If MAC can avoid all that, then why can't it also avoid tampering with > /dev? What security does your filesystem add at all, if it's useless > without a MAC doing all the hard work? I think the answer is obvious: Tetsuo wants to add functionality that the MACs are missing. So, instead of adding this functionality per MAC, he proposes to add it as ground work, to be combined with any MAC. > I think you can better spend your time on read-only bind mounts. That would be too coarse. Thanks! -- Al