[Samba] Numerically large UID issues (I think)

[Rowland Penny]

On Wed, 2022-03-30 at 07:44 -0500, Patrick Goetz via samba wrote:
> I'm trying to do an Ubuntu 20.04 Samba-only (i.e. no sssd)
> deployment 
> against the University's somewhat Rube Goldberg AD, and am running in
> to 
> issues.  In particular
> 
> root at cns-khl-files:/etc# getent passwd pgoetz
> pgoetz:*:10224688:10000513::/home/pgoetz:/bin/bash
> root at cns-khl-files:/etc# getent passwd jm88942
> root at cns-khl-files:/etc#
> 
> So, getent passwd works for me, but not for username jm88942.  Using 
> Powershell:
> 
> ------------------------------------------
> PS C:\Users\cns-pgoetz> get-aduser pgoetz
> 
> DistinguishedName : CN=Goetz Patrick G 
> (pgoetz),OU=Austinites,OU=People,DC=austin,DC=utexas,DC=edu
> Enabled           : True
> ObjectClass       : user
> ObjectGUID        : 8c30a807-88a1-4e68-8274-6cf88839223b
> SamAccountName    : pgoetz
> SID               : S-1-5-21-527237240-963894560-725345543-224688
> 
> 
> PS C:\Users\cns-pgoetz> get-aduser jm88942
> 
> DistinguishedName : CN=XXX 
> (jm88942),OU=Austinites,OU=People,DC=austin,DC=utexas,DC=edu
> Enabled           : True
> ObjectClass       : user
> ObjectGUID        : f3c6665c-eee0-4f00-b514-f4c7a773a86f
> SamAccountName    : jm88942
> SID               : S-1-5-21-527237240-963894560-725345543-10188858
> ------------------------------------------
> 
> Notice that my RID is 224688 while jm88942's is numerically larger:
> 10188858
> 
> Here is the RID mapping from smb.conf:
> 
>     idmap config * : backend = tdb
>     idmap config * : range = 3000-9999
>     idmap config AUSTIN : backend = rid
>     idmap config AUSTIN : range = 10000000-10999999
> 
> I had originally set the base to 1000000, noticed the problem and 
> increased the base to 10000000, but this doesn't seem to have helped.

Sorry but that will not help, you should have raised the high range.
The rid idmap backend uses this calculation:

ID = RID - BASE_RID + LOW_RANGE_ID

The BASE_RID is 0 unless you set it in smb.conf, so that becomes:

ID = RID + LOW_RANGE_ID

Which in your case is:

11188858 = 10188858 + 1000000

And '11188858' is larger than your high range '10999999'. This means it
will be ignored, just add a '9' to the end of your high range (and put
the low range back to what it was.

Rowland