mkdir-dup test flapping

[Andrew Bartlett]

G'Day Jeremy,

In testing Samba on the Catalyst Cloud, we more often than not get a
flapping test failure, rather than our real issues.  One that has come
particularly to my attention is

[438(1936)/1885 at 1h5m1s] samba3.smb2.create(ad_dc)
Testing SMB2 Create Directory with multiple connections
waiting for replies
UNEXPECTED(failure): samba3.smb2.create.mkdir-dup(ad_dc)
REASON: Exception: Exception: ../source4/torture/smb2/create.c:1628:
File 1 returned status NT_STATUS_ACCESS_DENIED

FAILED (1 failures, 0 errors and 0 unexpected successes in 0
testsuites)

This is your code in 969d043596c0a382325d54d16dbd5e049f884fa9 testing  
https://bugzilla.samba.org/show_bug.cgi?id=11486

ad_dc here uses the smbd file server (no, this isn't NTVFS :-)

Can you look into this for us, and perhaps see if the code could be
made more robust during the loop?  I'm very happy to get you access to
a suitable machine to show the issue, but sadly it only seems to
reproduce easily in a full autobuild (along with all the other flapping
tests).

Thanks,

Andrew Bartlett

-- 
Andrew Bartlett
https://samba.org/~abartlet/
Authentication Developer, Samba Team         https://samba.org
Samba Development and Support, Catalyst IT   
https://catalyst.net.nz/services/samba