From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id 13B527F4E for ; Wed, 11 Dec 2013 21:39:07 -0600 (CST) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay1.corp.sgi.com (Postfix) with ESMTP id EA78A8F8049 for ; Wed, 11 Dec 2013 19:39:06 -0800 (PST) Received: from fieldses.org (fieldses.org [174.143.236.118]) by cuda.sgi.com with ESMTP id Edv2veOVGDPtuMd0 (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Wed, 11 Dec 2013 19:39:05 -0800 (PST) Date: Wed, 11 Dec 2013 22:38:59 -0500 From: "J. Bruce Fields" Subject: Re: [PATCH] nfsd: revoking of suid/sgid bits after chown() in a consistent way Message-ID: <20131212033859.GA5978@fieldses.org> References: <20131206204747.GB12613@fieldses.org> <1386756996-28083-1-git-send-email-stanislav.kholmanskikh@oracle.com> <52A845C6.2080109@oracle.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <52A845C6.2080109@oracle.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Stanislav Kholmanskikh Cc: vasily.isaenko@oracle.com, hch@infradead.org, linux-nfs@vger.kernel.org, sprabhu@redhat.com, xfs@oss.sgi.com On Wed, Dec 11, 2013 at 03:00:22PM +0400, Stanislav Kholmanskikh wrote: > > > On 12/11/2013 02:16 PM, Stanislav Kholmanskikh wrote: > [cut off] > > > >This patch makes NFS to behave like local file systems. > > > [cut off] > > This patch allows to run generic/193 without any issues with NFSv3. > > With NFSv4 generic/193 fails (but with the other issues, which > existed even before the patch). > > generic/193 expects that suid/sgid bits are cleared after the file > truncation: > > touch file > chown fsgqa:fsgqa file > chmod u+s file > echo 'xyz' > file > ls -l file > su fsgqa -c 'echo > file' > ls -l file > > With ext4 (for example), we have expectable results: > -rwSr--r-- 1 fsgqa fsgqa 4 Dec 11 05:21 file > -rw-r--r-- 1 fsgqa fsgqa 1 Dec 11 05:22 file > > With NFSv3 as well: > -rwSr--r-- 1 fsgqa fsgqa 4 Dec 11 05:24 file > -rw-r--r-- 1 fsgqa fsgqa 1 Dec 11 05:25 file > > But with NFSv4 the bits are not cleared: > -rwSr--r-- 1 fsgqa fsgqa 1 Dec 11 05:19 file > -rwSr--r-- 1 fsgqa fsgqa 1 Dec 11 05:21 file > > 'echo > file' issues: > > open("file", O_WRONLY|O_CREAT|O_TRUNC, 0666) > > Can it be because of design differences between NFSv3 and NFSv4? In the v3 case I'd expect the open O_TRUNC to result in a SETATTR rpc, in the v4 case an OPEN rpc. Both result in a call to nfsd_setattr, though I only see nfsd_setattr turning off the SUID/SGID bits in the chown case. Are you sure it isn't the subsequent write that clears those bits? But looks to me like nfsd_vfs_write (used in both v3 & v4 cases) clears suid & guid, so I still don't see it. --b. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:48686 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751323Ab3LLDjE (ORCPT ); Wed, 11 Dec 2013 22:39:04 -0500 Date: Wed, 11 Dec 2013 22:38:59 -0500 From: "J. Bruce Fields" To: Stanislav Kholmanskikh Cc: linux-nfs@vger.kernel.org, vasily.isaenko@oracle.com, hch@infradead.org, xfs@oss.sgi.com, sprabhu@redhat.com Subject: Re: [PATCH] nfsd: revoking of suid/sgid bits after chown() in a consistent way Message-ID: <20131212033859.GA5978@fieldses.org> References: <20131206204747.GB12613@fieldses.org> <1386756996-28083-1-git-send-email-stanislav.kholmanskikh@oracle.com> <52A845C6.2080109@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <52A845C6.2080109@oracle.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Wed, Dec 11, 2013 at 03:00:22PM +0400, Stanislav Kholmanskikh wrote: > > > On 12/11/2013 02:16 PM, Stanislav Kholmanskikh wrote: > [cut off] > > > >This patch makes NFS to behave like local file systems. > > > [cut off] > > This patch allows to run generic/193 without any issues with NFSv3. > > With NFSv4 generic/193 fails (but with the other issues, which > existed even before the patch). > > generic/193 expects that suid/sgid bits are cleared after the file > truncation: > > touch file > chown fsgqa:fsgqa file > chmod u+s file > echo 'xyz' > file > ls -l file > su fsgqa -c 'echo > file' > ls -l file > > With ext4 (for example), we have expectable results: > -rwSr--r-- 1 fsgqa fsgqa 4 Dec 11 05:21 file > -rw-r--r-- 1 fsgqa fsgqa 1 Dec 11 05:22 file > > With NFSv3 as well: > -rwSr--r-- 1 fsgqa fsgqa 4 Dec 11 05:24 file > -rw-r--r-- 1 fsgqa fsgqa 1 Dec 11 05:25 file > > But with NFSv4 the bits are not cleared: > -rwSr--r-- 1 fsgqa fsgqa 1 Dec 11 05:19 file > -rwSr--r-- 1 fsgqa fsgqa 1 Dec 11 05:21 file > > 'echo > file' issues: > > open("file", O_WRONLY|O_CREAT|O_TRUNC, 0666) > > Can it be because of design differences between NFSv3 and NFSv4? In the v3 case I'd expect the open O_TRUNC to result in a SETATTR rpc, in the v4 case an OPEN rpc. Both result in a call to nfsd_setattr, though I only see nfsd_setattr turning off the SUID/SGID bits in the chown case. Are you sure it isn't the subsequent write that clears those bits? But looks to me like nfsd_vfs_write (used in both v3 & v4 cases) clears suid & guid, so I still don't see it. --b.