From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2A8EC2D0DC for ; Thu, 26 Dec 2019 03:56:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B22362075E for ; Thu, 26 Dec 2019 03:56:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726911AbfLZD4a (ORCPT ); Wed, 25 Dec 2019 22:56:30 -0500 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:41836 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726741AbfLZD43 (ORCPT ); Wed, 25 Dec 2019 22:56:29 -0500 Received: from callcc.thunk.org (96-72-84-49-static.hfc.comcastbusiness.net [96.72.84.49] (may be forged)) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id xBQ3u6FI016271 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 25 Dec 2019 22:56:08 -0500 Received: by callcc.thunk.org (Postfix, from userid 15806) id 50146420485; Wed, 25 Dec 2019 22:56:06 -0500 (EST) Date: Wed, 25 Dec 2019 22:56:06 -0500 From: "Theodore Y. Ts'o" To: Florian Weimer Cc: Rich Felker , linux-fsdevel@vger.kernel.org, musl@lists.openwall.com, linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org Subject: Re: [musl] getdents64 lost direntries with SMB/NFS and buffer size < unknown threshold Message-ID: <20191226035606.GB10794@mit.edu> References: <20191120001522.GA25139@brightrain.aerifal.cx> <8736eiqq1f.fsf@mid.deneb.enyo.de> <20191120205913.GD16318@brightrain.aerifal.cx> <20191121175418.GI4262@mit.edu> <87a77g2o2o.fsf@mid.deneb.enyo.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87a77g2o2o.fsf@mid.deneb.enyo.de> Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Wed, Dec 25, 2019 at 08:38:07PM +0100, Florian Weimer wrote: > 32 bits are simply not enough storage space for the cookie. Hashing > just masks the presence of these bugs, but does not eliminate them > completely. Arguably 64 bits is not enough space for the cookie. I'd be a lot happier if it was 128 or 256 bits. This is just one of those places where POSIX is Really Broken(tm). Unfortunately, NFS only gives us 64 bits for the readdir/readdirplus cookie, so we're kind of stuck with it. - Ted