Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753826AbYKFUxW (ORCPT ); Thu, 6 Nov 2008 15:53:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751456AbYKFUwu (ORCPT ); Thu, 6 Nov 2008 15:52:50 -0500 Received: from e6.ny.us.ibm.com ([32.97.182.146]:36776 "EHLO e6.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751225AbYKFUwr (ORCPT ); Thu, 6 Nov 2008 15:52:47 -0500 Subject: Re: [PATCH 0/5] eCryptfs: Filename Encryption From: Dave Kleikamp To: mhalcrow@linux.vnet.ibm.com Cc: Pavel Machek , Andrew Morton , LKML , Dustin Kirkland , Eric Sandeen , Tyler C Hicks , David Kleikamp In-Reply-To: <20081106202736.GC6688@halcrowt61p.austin.ibm.com> References: <20081104213754.GC6675@halcrowt61p.austin.ibm.com> <20081105155754.GA1759@ucw.cz> <20081106202736.GC6688@halcrowt61p.austin.ibm.com> Content-Type: text/plain Date: Thu, 06 Nov 2008 14:52:26 -0600 Message-Id: <1226004746.8898.6.camel@norville.austin.ibm.com> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1285 Lines: 28 On Thu, 2008-11-06 at 14:27 -0600, mhalcrow@linux.vnet.ibm.com wrote: > On Wed, Nov 05, 2008 at 04:57:54PM +0100, Pavel Machek wrote: > > On Tue 2008-11-04 15:37:54, Michael Halcrow wrote: > > > This patchset implements filename encryption via a > > > passphrase-derived mount-wide Filename Encryption Key (FNEK) > > > specified as a mount parameter. Each encrypted filename has a > > > fixed prefix indicating that eCryptfs should try to decrypt the > > > filename. When eCryptfs encounters > > > > That is 'interesting'. What happens if normal filename has that > > prefix? > > If the lower filename has the prefix but does not have a valid tag 70 > packet following the prefix, then eCryptfs will complain in the syslog > and then pass through the lower filename as-is. I'd recommend hiding this kind of syslog verbosity behind a debug config option. I think it would be very easy to create a DOS attack against ecryptfs by putting all sorts of clever things in the lower file system. -- David Kleikamp IBM Linux Technology Center -- 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/