From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: NeilBrown , Trond Myklebust , Kamal Mostafa Subject: [PATCH 3.13.y-ckt 22/85] NFSv4: don't set SETATTR for O_RDONLY|O_EXCL Date: Tue, 20 Oct 2015 14:34:38 -0700 Message-Id: <1445376941-7046-23-git-send-email-kamal@canonical.com> In-Reply-To: <1445376941-7046-1-git-send-email-kamal@canonical.com> References: <1445376941-7046-1-git-send-email-kamal@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.13.11-ckt28 -stable 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 Signed-off-by: Kamal Mostafa --- fs/nfs/nfs4proc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index a9902fb..902a16e 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2272,7 +2272,7 @@ static int _nfs4_do_open(struct inode *dir, goto err_free_label; state = ctx->state; - if ((opendata->o_arg.open_flags & O_EXCL) && + if ((opendata->o_arg.open_flags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL) && (opendata->o_arg.createmode != NFS4_CREATE_GUARDED)) { nfs4_exclusive_attrset(opendata, sattr); -- 1.9.1