[Samba] "Samba 4" - "smbd"; "can't parse the PAC: NT_STATUS_BUFFER_TOO_SMALL" error but only for a single domain user ("Server 2008 R2" domain, "Server 2008" functional level forest).

[Tris Mabbs]

>> 	So it seems that with these changes, "kerberos_decode_pac()" is never 
>> entered with "client_principal" anything other than a NULL pointer.
>> 
>> So I'm (very) happy that these changes fix my problem.  However it 
>> does seem a little curious that "client_principal" now never appears 
>> to be set - I don't know whether that's expected behaviour?
>
> It isn't, we need to look into that some more. 

	More than happy to - let me know what you want put where and it'll be done.

	Meanwhile, having cleared them out recently, I currently have ~3,600 PAC dumps, not a single one with the Kerberos principal in the name (every one's a PID based name).

	On the plus side, still nary a core dump:

------->Cut here:
# find /var/samba4/log/cores/ -type f
#
<-------Cut here.

> Does the ndrdump run you did before now pass fine?

	Yes, runs perfectly:

------->Cut here:
% /var/tmp/samba/samba-master/samba-gd/bin/ndrdump krb5pacdecode_pac in PAC-NDR-1819
pull returned NT_STATUS_OK
    decode_pac: struct decode_pac
        in: struct decode_pac
            pac: struct PAC_DATA
                num_buffers              : 0x00000005 (5)
                version                  : 0x00000000 (0)
                buffers: ARRAY(5)
                    buffers: struct PAC_BUFFER
                        type                     : PAC_TYPE_LOGON_INFO (1)
                        _ndr_size                : 0x00000248 (584)
                        info                     : *
                            info                     : union PAC_INFO(case 1)
                            logon_info: struct PAC_LOGON_INFO_CTR

...

                    buffers: struct PAC_BUFFER
                        type                     : PAC_TYPE_KDC_CHECKSUM (7)
                        _ndr_size                : 0x00000014 (20)
                        info                     : *
                            info                     : union PAC_INFO(case 7)
                            kdc_cksum: struct PAC_SIGNATURE_DATA
                                type                     : KERB_CHECKSUM_HMAC_MD
5 (0xFFFFFF76)
                                signature                : DATA_BLOB length=16
[0000] 3B 96 CC BB BB 9D E4 57   13 C9 6D 1C 65 A0 B1 1B   ;......W ..m.e...
                                RODCIdentifier           : 0x0000 (0)
                        _pad                     : 0x00000000 (0)
dump OK
%
<------- Cut here.

Large amounts of data, all looking absolutely fine.

So definite progress ...

Many thanks, regards, and have a great weekend everyone,

Tris.