On Fri, 12 Dec 2025 07:35:21 -0500, Robert S. Hansel 
<[email protected]> wrote:

>Are native Unix controls (Owner,Group,Other permission bits) being used to 
>govern access in Unix or has it been externalized such that ACF2 rules are 
>governing access?
> If the latter, UID may not matter unless you are planning on converting to 
> RACF.

Fixing UID shifts the problem to GID. I suggest you either skip or delay this 
until you create a well-defined UID, GID, OTHER and ownership strategy. You 
don't want to repeat this process again.

May I suggest considering an alternate approach that might be easier:

1. I would focus on the subdirectories of /u. Correcting files doesn't retrain 
habits learned in an unsecured environment. This is the typical location for 
user and group directories.  /tmp is another location where user files are 
located.

2. Definition: "group" directories are the /u directories that aren't used as 
any SAF user's unix home. These directories are primarily accessed using a 
group permissions. I suspect there will be very few because it was too easy to 
use someone's home directory as a group directory.

3. Definition: "home" directories are the home directories defined in a SAF 
user's unix home definition. 

4. You only need to secure each /u subdirectory using chmod (440 or 400), chown 
and chgrp. Files and subdirectories default to chmod 444 which gives other 
permission to the files (try touch uuu to verify). Leave it up to the users to 
secure their files 

5. The difficult problem is determining group files in home directories and how 
they fit into your strategy. Do you allow group files to remain in home 
directories or create group directories.
 
6. Considerations & changes for each directory in /u:
6a. To simplify conversion, authorize your common GID to everyone.
6b. Investigate files & subdirectories that do not have the common UID & GID.
6c. Investigate files & subdirectories  are the the common ones
6d. Review the impact of hardlinks in bypassing security.
6e. Propagating owner and group to each file and subdirectory in /u.  

This method allows you to ignore files and simplify the process. This is not a 
complete list but you can ask questions if this an alternative you want to 
pursue.

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