From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Tso Subject: Re: Versioning file system Date: Tue, 19 Jun 2007 03:01:21 -0400 Message-ID: <20070619070121.GA9177@thunk.org> References: <8wsW4-3UY-3@gated-at.bofh.it> <8wJal-3KA-1@gated-at.bofh.it> <8xm22-4Ql-1@gated-at.bofh.it> <8xq5G-32l-7@gated-at.bofh.it> <8xs7w-69W-21@gated-at.bofh.it> <4676F9A2.6010007@zytor.com> <20070618221021.GB2062@thunk.org> <20070618222656.GB25089@lazybastard.org> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "H. Peter Anvin" , alan , Bodo Eggert <7eggert@gmx.de>, Jack Stone , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, akpm@linux-foundation.org, viro@zeniv.linux.org.uk To: =?iso-8859-1?Q?J=F6rn?= Engel Return-path: Received: from THUNK.ORG ([69.25.196.29]:47890 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755729AbXFSHC2 (ORCPT ); Tue, 19 Jun 2007 03:02:28 -0400 Content-Disposition: inline In-Reply-To: <20070618222656.GB25089@lazybastard.org> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Tue, Jun 19, 2007 at 12:26:57AM +0200, J=F6rn Engel wrote: > The main difference appears to be the potential size. Both extended > attributes and forks allow for extra data that I neither want or need= =2E > But once the extra space is large enough to hide a rootkit in, it > becomes a security problem instead of just something pointless. The other difference is that you can't execute an extended attribute. You can store kvm/qemu, a complete virtualization enviroment, shared libraries, and other executables all inside a forks inside a file, and then execute programs/rootkit out of said file fork(s). As I mentioned in my LCA presentation, one system administrator refused to upgrade beyond Solaris 8 because he thought forks were good for nothing but letting system crackers hide rootkits that wouldn't be detected by programs like tripwire. The question then is why in the world would we want to replicate Sun's mistakes? - Ted - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html