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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 4B180C04EB8 for ; Wed, 5 Dec 2018 01:04:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 16CC220850 for ; Wed, 5 Dec 2018 01:04:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 16CC220850 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com 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 S1726082AbeLEBEe (ORCPT ); Tue, 4 Dec 2018 20:04:34 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:47721 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725979AbeLEBEe (ORCPT ); Tue, 4 Dec 2018 20:04:34 -0500 Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id A716487AAD095; Wed, 5 Dec 2018 09:04:31 +0800 (CST) Received: from [127.0.0.1] (10.184.213.217) by DGGEMS403-HUB.china.huawei.com (10.3.19.203) with Microsoft SMTP Server id 14.3.408.0; Wed, 5 Dec 2018 09:04:24 +0800 Subject: Re: [PATCH] nfsd: Return EPERM on utime/utimes/lutimes calls instead of EACCESS in some cases To: "J. Bruce Fields" CC: , , , References: <1543564290-147370-1-git-send-email-zhengbin13@huawei.com> <4e0152c4-bbe9-4246-27ee-bae2fee9129d@huawei.com> <20181204201357.GC3903@fieldses.org> From: "zhengbin (A)" Message-ID: Date: Wed, 5 Dec 2018 09:04:22 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: <20181204201357.GC3903@fieldses.org> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.184.213.217] X-CFilter-Loop: Reflected Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org thanks, >>> As the man(3) page for utime/utimes/lutimes, EPERM is returned -------->this should be As the man page for utime/utimes/lutimes, my little mistake. utime/utimes are man(2), lutimes is man(3) I send v2 patch?Or when you apply, help modify it? On 2018/12/5 4:13, J. Bruce Fields wrote: > On Mon, Dec 03, 2018 at 04:36:27PM +0800, zhengbin (A) wrote: >> hi, J. Bruce Fields, Jeff Layton >> >> When you have time, confirm it? thanks > > Sorry for the delay. > > The patch looks good to me. > > As far as I can tell, we've done this forever. And I'm a little worried > about changing such long-standing behavior, but I think you're right. > > So, applying for for 4.21. > > --b. > >> On 2018/11/30 15:51, zhengbin wrote: >>> As the man(3) page for utime/utimes/lutimes, EPERM is returned >>> when the second parameter of utime/utimes/lutimes is not NULL, >>> the caller's effective UID does not match the owner of the file, >>> and the caller is not privileged. >>> >>> However, in a NFS directory, it will return EACCESS(nfsd_setattr-> >>> fh_verify->nfsd_permission), This patch fix this. >>> >>> Signed-off-by: zhengbin >>> --- >>> fs/nfsd/vfs.c | 17 +++++++++++++++-- >>> 1 file changed, 15 insertions(+), 2 deletions(-) >>> >>> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c >>> index eb67098..9824e32 100644 >>> --- a/fs/nfsd/vfs.c >>> +++ b/fs/nfsd/vfs.c >>> @@ -396,10 +396,23 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, >>> bool get_write_count; >>> bool size_change = (iap->ia_valid & ATTR_SIZE); >>> >>> - if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE)) >>> + if (iap->ia_valid & ATTR_SIZE) { >>> accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE; >>> - if (iap->ia_valid & ATTR_SIZE) >>> ftype = S_IFREG; >>> + } >>> + >>> + /* >>> + * If utimes(2) and friends are called with times not NULL, we should >>> + * not set NFSD_MAY_WRITE bit. Otherwise fh_verify->nfsd_permission >>> + * will return EACCESS, when the caller's effective UID does not match >>> + * the owner of the file, and the caller is not privileged. In this >>> + * situation, we should return EPERM(notify_change will return this). >>> + */ >>> + if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME)) { >>> + accmode |= NFSD_MAY_OWNER_OVERRIDE; >>> + if (!(iap->ia_valid & (ATTR_ATIME_SET | ATTR_MTIME_SET))) >>> + accmode |= NFSD_MAY_WRITE; >>> + } >>> >>> /* Callers that do fh_verify should do the fh_want_write: */ >>> get_write_count = !fhp->fh_dentry; >>> -- >>> 2.7.4 >>> >>> >>> . >>> > > . >