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=-10.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 BFEB7C43387 for ; Fri, 11 Jan 2019 14:44:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9267320872 for ; Fri, 11 Jan 2019 14:44:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547217880; bh=PDGhRl3P3HViSQ8R7Jrh3BDjmi0Z6/Lm0NKkaC+9koo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IvsvAf+CTZ10R2ey58TlMU4uBoUxHhUaWQ91I11YcgbFpkUUAPvrG5BPi0+HNGvi7 Uh4KdewJJ1PJ/7szSi2Nuj/kURf69tvlbBToW1nOZg3x1vfnEeduXvAlU44CXFoqMI h4lHqJSC5g7QVx2ZXxUmrTzua3sX7OUuiKAc2Kfg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404626AbfAKOoj (ORCPT ); Fri, 11 Jan 2019 09:44:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:37522 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404202AbfAKOoe (ORCPT ); Fri, 11 Jan 2019 09:44:34 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 80D3B20872; Fri, 11 Jan 2019 14:44:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547217874; bh=PDGhRl3P3HViSQ8R7Jrh3BDjmi0Z6/Lm0NKkaC+9koo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fVKSnapzhmlcK9ebZ+FQgvhVre+rU22GgVazcwmfG/04ysXsHjzwetWGTrg0eI1Vq QGRM+c213w1UkGd1Lf8skXMTwyfDW4sQkUYuRbXaOas7EmhnQm9pnrIWVcZpGtpieH TrGFMTaA6AaWjWNR5zU4Z+C1qQEL1sg0Mp+GFSbo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chuck Lever , "J. Bruce Fields" Subject: [PATCH 4.20 40/65] nfsd4: zero-length WRITE should succeed Date: Fri, 11 Jan 2019 15:15:26 +0100 Message-Id: <20190111131102.049766318@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190111131055.331350141@linuxfoundation.org> References: <20190111131055.331350141@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: J. Bruce Fields commit fdec6114ee1f0f43b1ad081ad8d46b23ba126d70 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfs4proc.c | 2 -- 1 file changed, 2 deletions(-) --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1016,8 +1016,6 @@ nfsd4_write(struct svc_rqst *rqstp, stru 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,