From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759418AbbJIAS6 (ORCPT ); Thu, 8 Oct 2015 20:18:58 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35360 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758957AbbJIARb (ORCPT ); Thu, 8 Oct 2015 20:17:31 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Trond Myklebust" , "NeilBrown" Date: Fri, 09 Oct 2015 01:12:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 042/107] NFSv4: don't set SETATTR for O_RDONLY|O_EXCL In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.247 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.72-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: NeilBrown commit efcbc04e16dfa95fef76309f89710dd1d99a5453 upstream. It is unusual to combine the open flags O_RDONLY and O_EXCL, but it appears that libre-office does just that. [pid 3250] stat("/home/USER/.config", {st_mode=S_IFDIR|0700, st_size=8192, ...}) = 0 [pid 3250] open("/home/USER/.config/libreoffice/4-suse/user/extensions/buildid", O_RDONLY|O_EXCL NFSv4 takes O_EXCL as a sign that a setattr command should be sent, probably to reset the timestamps. When it was an O_RDONLY open, the SETATTR command does not identify any actual attributes to change. If no delegation was provided to the open, the SETATTR uses the all-zeros stateid and the request is accepted (at least by the Linux NFS server - no harm, no foul). If a read-delegation was provided, this is used in the SETATTR request, and a Netapp filer will justifiably claim NFS4ERR_BAD_STATEID, which the Linux client takes as a sign to retry - indefinitely. So only treat O_EXCL specially if O_CREAT was also given. Signed-off-by: NeilBrown Signed-off-by: Trond Myklebust [bwh: Backported to 3.2: we only check open_flags, not createmode as well] Signed-off-by: Ben Hutchings --- fs/nfs/nfs4proc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -1793,7 +1793,7 @@ static int _nfs4_do_open(struct inode *d if (server->caps & NFS_CAP_POSIX_LOCK) set_bit(NFS_STATE_POSIX_LOCKS, &state->flags); - if (opendata->o_arg.open_flags & O_EXCL) { + if ((opendata->o_arg.open_flags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL)) { nfs4_exclusive_attrset(opendata, sattr); nfs_fattr_init(opendata->o_res.f_attr);