Return-Path: Received: from mail-vn0-f44.google.com ([209.85.216.44]:33921 "EHLO mail-vn0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754577AbbE1WY3 convert rfc822-to-8bit (ORCPT ); Thu, 28 May 2015 18:24:29 -0400 Received: by vnbf129 with SMTP id f129so6444420vnb.1 for ; Thu, 28 May 2015 15:24:28 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <8d601ee8babe5239b7926542c713c58502b15e35.1429868795.git.agruenba@redhat.com> <20150528203332.GD31663@fieldses.org> Date: Thu, 28 May 2015 18:24:28 -0400 Message-ID: Subject: Re: [RFC v3 36/45] NFSv4: Fix GETATTR bitmap verification From: Trond Myklebust To: =?UTF-8?Q?Andreas_Gr=C3=BCnbacher?= Cc: "J. Bruce Fields" , Linux Kernel Mailing List , Linux FS-devel Mailing List , Linux NFS Mailing List Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Thu, May 28, 2015 at 6:09 PM, Andreas Grünbacher wrote: > 2015-05-28 23:55 GMT+02:00 Trond Myklebust : >>> We already do this kind of check with the existing code. What's wrong with it? >> >> Actually, you're right, we don't check for the previous word, however >> fixing that is a question of adding 2 extra checks in >> decode_getfattr_attrs(), one in decode_getfattr_statfs(), and one in >> decode_fsinfo(). >> >> It shouldn't require a rewrite of the entire nfs4xdr.c. > > I would actually prefer either verifying the reply bitmap against the > request bitmap, > or checking the bitmap first as this patch does --- the current > approach of knocking > individual bits over and checking if any "before" bits have been missed isn't > exactly what I would take as a textbook example. ...and I'd prefer that we don't keep rewriting code that works. Screw the textbooks... Trond