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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 0A28EC43441 for ; Mon, 19 Nov 2018 19:59:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CBF5D20831 for ; Mon, 19 Nov 2018 19:59:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CBF5D20831 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=fieldses.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nfs-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730219AbeKTGYt (ORCPT ); Tue, 20 Nov 2018 01:24:49 -0500 Received: from fieldses.org ([173.255.197.46]:57166 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725963AbeKTGYt (ORCPT ); Tue, 20 Nov 2018 01:24:49 -0500 Received: by fieldses.org (Postfix, from userid 2815) id B492A2016; Mon, 19 Nov 2018 14:59:37 -0500 (EST) Date: Mon, 19 Nov 2018 14:59:37 -0500 From: Bruce Fields To: Chuck Lever Cc: linux-rdma , Linux NFS Mailing List Subject: Re: [PATCH v1 3/4] NFSD: Refactor the generic write vector fill helper Message-ID: <20181119195937.GB22976@fieldses.org> References: <20180727142007.21878.77494.stgit@klimt.1015granger.net> <20180727151905.21878.62693.stgit@klimt.1015granger.net> <20181115163246.GB9022@fieldses.org> <20181119195442.GA22976@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Mon, Nov 19, 2018 at 02:58:17PM -0500, Chuck Lever wrote: > Should I send you a patch? I'm applying the following. --b. commit fc4ee8d8a5f7 Author: J. Bruce Fields Date: Thu Nov 15 11:21:40 2018 -0500 nfsd4: zero-length WRITE should succeed Zero-length writes are legal; from 5661 section 18.32.3: "If the count is zero, the WRITE will succeed and return a count of zero subject to permissions checking". This check is unnecessary and is causing zero-length reads to return EINVAL. Cc: stable@vger.kernel.org Fixes: 3fd9557aec91 "NFSD: Refactor the generic write vector fill helper" Cc: Chuck Lever Signed-off-by: J. Bruce Fields diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index d505990dac7c..c364acbb6aba 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1016,8 +1016,6 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, nvecs = svc_fill_write_vector(rqstp, write->wr_pagelist, &write->wr_head, write->wr_buflen); - if (!nvecs) - return nfserr_io; WARN_ON_ONCE(nvecs > ARRAY_SIZE(rqstp->rq_vec)); status = nfsd_vfs_write(rqstp, &cstate->current_fh, filp,