samba - Sep 2011 - Anyone can create empty files (v 3.5.11)

I've mounted my cifs partition with a username and password and to
test whether I had my permissions right, I did:

$ sudo su testuser
$ touch asdf
touch: cannot touch `asdf': Permission denied
$

It says permission denied, but the `asdf' file is still created.  I
can't write any data to it, but I can create empty files.

This is because in smbd/open.c if the file doesn't exist and O_CREAT
flag is set then it lets you open the file without checking
smbd_check_open_rights().

Or am I doing something wrong?  I'm using Debian testing (wheezy).

regards,
dan carpenter

From: Dan Carpenter <dan.carpenter at oracle.com>
Date: Fri, 23 Sep 2011 09:38:56 +0300
> I've mounted my cifs partition with a username and password and to
> test whether I had my permissions right, I did:
> 
> $ sudo su testuser
> $ touch asdf
> touch: cannot touch `asdf': Permission denied
> $
> 
> It says permission denied, but the `asdf' file is still created.  I
> can't write any data to it, but I can create empty files.
How does "ls -l asdf"?

By default, the permission and owner for a created file is forcibily
set on "root 644 because CIFS server (Windows server) essentially does 
not have semantics of permission. That sometimes causes an odd
behavior that you have met.

Try noperm option as mentioned:
  https://lists.samba.org/archive/samba/2011-September/163986.html

---
TAKAHASHI Motonobu <monyo at samba.gr.jp>