Unless something drastic has changed in 2012, the following should work.
Set the share on the server (in your case UserData$) with Full Control for the Admins/Domain Admins, and Everyone as "Change and Read".
On the NTFS folder "UserData" set the permissions explicit without inheritance and only grant Domain Admins Full control, along with anyone outside of Domain Admins that needs to see all folders.
Then when you create the user in AD and set their home folder that subfolder %username% will automically be granted Full Control for that user. Since they can traverse the UserData folder to map a drive to \server01\UserData$\%username% they get access to only that folder. Mapping a drive to \server01\UserData$ will be useless for them.
That's how we've always set ours up over the years.
Now with 2012 you can easily enable ABE http://heineborn.com/tech/enable-access-based-enumeration-in-windows-server-2012/ where the users only see folders they have rights to, but this isn't even necessary if you do the above.