[PATCH 0/13] add SMB2 server-side copy support - V2

[Jeremy Allison]

On Thu, Dec 06, 2012 at 02:15:44PM +0100, David Disseldorp wrote:
> On Wed, 28 Nov 2012 20:00:50 -0800
> Jeremy Allison <jra at samba.org> wrote:
> 
> > > > I think inside fsctl_srv_copychunk_send() you should have a check
> > > > similar to the one inside source3/smbd/smb2_write. Look for
> > > > the CHECK_WRITE macro inside that file for details.  
> > > 
> > > Good catch, looks like a CHECK_READ on the src_fsp is also needed.  
> > 
> > Oh - good point, I forgot about that one too !
> 
> Strangely Windows servers do not appear to check the open-time granted
> access on the source file. This behaviour matches what is documented in
> [MS-SMB2] 3.3.5.15.6 Handling a Server-Side Data Copy Request, where
> only the destination file is checked for open-time granted read and
> write access.
> 
> I'll drop the src_fsp check for now, dest_fsp will be checked for read
> and write access. New round of patches with a bunch more torture tests
> is on its way.

I don't think we can do that can we ?

Imagine the following, a "super-secure" file is opened with READ_ATTRIBUTES
only, then used as a copychunk source handle to copy data from it into a
"non-secure" file.

I think we have to have the read check on the source file.

Jeremy.