From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932591AbcHNK6V (ORCPT ); Sun, 14 Aug 2016 06:58:21 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:51846 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932441AbcHNK6T (ORCPT ); Sun, 14 Aug 2016 06:58:19 -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, "Anna Schumaker" , "Olga Kornievskaia" , "Trond Myklebust" Date: Sat, 13 Aug 2016 18:42:58 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 74/94] NFS: Fix another OPEN_DOWNGRADE bug In-Reply-To: X-SA-Exim-Connect-IP: 92.40.249.202 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 3.2.82-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust commit e547f2628327fec6afd2e03b46f113f614cca05b upstream. Olga Kornievskaia reports that the following test fails to trigger an OPEN_DOWNGRADE on the wire, and only triggers the final CLOSE. fd0 = open(foo, RDRW) -- should be open on the wire for "both" fd1 = open(foo, RDONLY) -- should be open on the wire for "read" close(fd0) -- should trigger an open_downgrade read(fd1) close(fd1) The issue is that we're missing a check for whether or not the current state transitioned from an O_RDWR state as opposed to having transitioned from a combination of O_RDONLY and O_WRONLY. Reported-by: Olga Kornievskaia Fixes: cd9288ffaea4 ("NFSv4: Fix another bug in the close/open_downgrade code") Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- fs/nfs/nfs4proc.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2025,12 +2025,11 @@ static void nfs4_close_prepare(struct rp call_close |= is_wronly; else if (is_wronly) calldata->arg.fmode |= FMODE_WRITE; + if (calldata->arg.fmode != (FMODE_READ|FMODE_WRITE)) + call_close |= is_rdwr; } else if (is_rdwr) calldata->arg.fmode |= FMODE_READ|FMODE_WRITE; - if (calldata->arg.fmode == 0) - call_close |= is_rdwr; - spin_unlock(&state->owner->so_lock); if (!call_close) {