From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-Id: <20120504204224.616378928@linuxfoundation.org> Date: Fri, 04 May 2012 13:42:27 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Trond Myklebust Subject: [ 03/75] NFSv4: Ensure that we check lock exclusive/shared type against open modes In-Reply-To: <20120504204258.GA12552@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust commit 55725513b5ef9d462aa3e18527658a0362aaae83 upstream. Since we may be simulating flock() locks using NFS byte range locks, we can't rely on the VFS having checked the file open mode for us. Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- fs/nfs/nfs4proc.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -4608,6 +4608,20 @@ nfs4_proc_lock(struct file *filp, int cm if (state == NULL) 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 & (F_RDLCK|F_WRLCK|F_UNLCK)) { + case F_RDLCK: + if (!(filp->f_mode & FMODE_READ)) + return -EBADF; + break; + case F_WRLCK: + if (!(filp->f_mode & FMODE_WRITE)) + return -EBADF; + } + do { status = nfs4_proc_setlk(state, cmd, request); if ((status != -EAGAIN) || IS_SETLK(cmd))