Greg KH wrote: > On Wed, Jul 18, 2001 at 03:32:48PM -0700, Crispin Cowan wrote: > > > > If someone has a practical, detailed way to construct the name, please > > speak up. Note that it is not sufficient to be able to construct *some* > > name that *could* have been used to open the file: we need the actual name > > that was used to make the request. > > > > On the other hand, if what you have is a heart-felt conviction that there > > must be some way to do it ... save it, we've heard that :-) We need the > > details, not the encouragement. > > I've said in private email to you and your group that there is a way to > do it, and outlined it. I can do it again here if you really want me > to. > > In short, you have to stop thinking of path names being the end all, and > have to start worrying about inodes _if_ you allow multiple mounts. > Just knowing the original path that was taken to get to a file isn't > going to help you out, you _need_ to know them all. Your private e-mail seemed to mis-understand the SubDomain security model. Yes, the absolute path name is the be-al and end-all that we need. What you outlined is an appropriate model for an ACL (access control list) model, but SubDomain is the dual of that. > If you don't allow multiple mounts, then you do not have a problem. A > inode has a dentry list which will contain only one dentry. Hence the > pathname to the file. As Seth alludes to, hard links are the other way a file can be aliased, and according to Chris, the inode (which is what we're presently hooking) provides a list of dentries, reflecting the hard link alias issue. If you're going to the advanced PLUG meeting tonight, we can chat about it. > I can write some specific code, based on the last release of SubDomain > to do this if you want proof, but I really don't want to do that :) We're not just being stubborn; Steve, Chris, and Seth spent two hours off-site today, trying to brainstorm a solution, and they keep hitting road blocks. This is a tough problem, and putting the name hook back is starting to look attractive. Crispin -- Crispin Cowan, Ph.D. Chief Scientist, WireX Communications, Inc. http://wirex.com Security Hardened Linux Distribution: http://immunix.org Available for purchase: http://wirex.com/Products/Immunix/purchase.html _______________________________________________ linux-security-module mailing list linux-security-moduleat_private http://mail.wirex.com/mailman/listinfo/linux-security-module
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