This is a note to let you know that I've just added the patch titled

NFS: Revert "NFS: Move the flock open mode check into nfs_flock()"

to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: nfs-revert-nfs-move-the-flock-open-mode-check-into-nfs_flock.patch and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From fcfa447062b2061e11f68b846d61cbfe60d0d604 Mon Sep 17 00:00:00 2001

From: Benjamin Coddington bcodding@redhat.com Date: Fri, 10 Nov 2017 06:27:49 -0500 Subject: NFS: Revert "NFS: Move the flock open mode check into nfs_flock()"

From: Benjamin Coddington bcodding@redhat.com

commit fcfa447062b2061e11f68b846d61cbfe60d0d604 upstream.

Commit e12937279c8b "NFS: Move the flock open mode check into nfs_flock()" changed NFSv3 behavior for flock() such that the open mode must match the lock type, however that requirement shouldn't be enforced for flock().

Signed-off-by: Benjamin Coddington bcodding@redhat.com Signed-off-by: Anna Schumaker Anna.Schumaker@Netapp.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- fs/nfs/file.c | 18 ++---------------- fs/nfs/nfs4proc.c | 14 ++++++++++++++ 2 files changed, 16 insertions(+), 16 deletions(-)

--- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -829,23 +829,9 @@ int nfs_flock(struct file *filp, int cmd if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FLOCK) is_local = 1;

- /* - * VFS doesn't require the open mode to match a flock() lock's type. - * NFS, however, may simulate flock() locking with posix locking which - * requires the open mode to match the lock type. - */ - switch (fl->fl_type) { - case F_UNLCK: + /* We're simulating flock() locks using posix locks on the server */ + if (fl->fl_type == F_UNLCK) return do_unlk(filp, cmd, fl, is_local); - case F_RDLCK: - if (!(filp->f_mode & FMODE_READ)) - return -EBADF; - break; - case F_WRLCK: - if (!(filp->f_mode & FMODE_WRITE)) - return -EBADF; - } - return do_setlk(filp, cmd, fl, is_local); } EXPORT_SYMBOL_GPL(nfs_flock); --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -6568,6 +6568,20 @@ nfs4_proc_lock(struct file *filp, int cm !test_bit(NFS_STATE_POSIX_LOCKS, &state->flags)) return -ENOLCK;

+ /* + * Don't rely on the VFS having checked the file open mode, + * since it won't do this for flock() locks. + */ + switch (request->fl_type) { + case F_RDLCK: + if (!(filp->f_mode & FMODE_READ)) + return -EBADF; + break; + case F_WRLCK: + if (!(filp->f_mode & FMODE_WRITE)) + return -EBADF; + } + status = nfs4_set_lock_state(state, request); if (status != 0) return status;

Patches currently in stable-queue which might be from bcodding@redhat.com are

queue-4.14/nfs-revert-nfs-move-the-flock-open-mode-check-into-nfs_flock.patch