samba - Oct 2012 - Unusual behavior when two users have different shares with the same name

Hi,

In our global smb.conf we have the line:

    include = /etc/smb/smb.%U.conf

which allows us to provide a different set of available shares to each user who
connects. Notably, two users might have shares with the same name, but which
point to different locations. And if both those users attempt to mount their own
homonymous shares from the same machine, they each see their own share. But this
breaks down if one of the users has already mounted something:

* Mount share foo as user A

* Mount share bar as user B

* Mount share bar as user A

* Observe that user A sees user B's version of bar

There is a workaround, which has inconsistent success:

* Unmount, then remount share bar as user A

* Observe that user A sees its own version of bar, as it should be

It seems to be related to the fact that the CIFS VFS layer only uses one TCP
connection for all the mounts; when we tried examining these shares with three
separate connections (using the smbclient tool), the users saw their own
versions of all the shares.

This was observed on samba 3.4.2 and 3.6.3, with mount.cifs up through version
5.6.

Is this a bug? Is it a use case which is simply beyond samba's scope? Any
clarifications would be much appreciated.

Regards,

--Jeff