From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Olga Kornievskaia , Trond Myklebust , Anna Schumaker Subject: [PATCH 4.6 055/203] NFS: Fix another OPEN_DOWNGRADE bug Date: Mon, 25 Jul 2016 13:54:30 -0700 Message-Id: <20160725203431.514421824@linuxfoundation.org> In-Reply-To: <20160725203429.221747288@linuxfoundation.org> References: <20160725203429.221747288@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.6-stable 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 Signed-off-by: Greg Kroah-Hartman --- fs/nfs/nfs4proc.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2860,12 +2860,11 @@ 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; - if (!nfs4_valid_open_stateid(state)) call_close = 0; spin_unlock(&state->owner->so_lock);