autobuild[sn-devel-184]: intermittent test failure detected

[autobuild]

The autobuild test system (on sn-devel-184) has detected an intermittent failing test in 
the current master tree.

The autobuild log of the failure is available here:

   https://git.samba.org/autobuild.flakey.sn-devel-184/2019-03-30-1002/flakey.log

The failure seems to be in the "samba-none-env" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-184/2019-03-30-1002/samba-none-env.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-184/2019-03-30-1002/samba-none-env.stdout
  
The top commit at the time of the failure was:

commit a2b1970a37836e46d6c9eb6bda9bd20185de96ce
Author: Garming Sam <garming at catalyst.net.nz>
Date:   Wed Mar 13 10:52:19 2019 +1300

    acl_read: Fix regression caused by db15fcfa899e1fe4d6994f68ceb299921b8aa6f1 for empty lists
    
    The original code never dereferenced attrs and only added "*" if attrs
    was NULL (not if attrs[0] was NULL).
    
    This causes significant performance issues with the new paged_results
    module introduced for 4.10 as the initial GUID search requests no
    attributes. This GUID search turns into a search for "*" and ends up
    allocating memory for the entire database.
    
    This never appears to cause changes in the final result set, only
    intermediate processing.
    
    BUG: https://bugzilla.samba.org/show_bug.cgi?id=13836
    
    Signed-off-by: Garming Sam <garming at catalyst.net.nz>
    Reviewed-by: Andrew Bartlett <abartlet at samba.org>
    
    Autobuild-User(master): Andrew Bartlett <abartlet at samba.org>
    Autobuild-Date(master): Fri Mar 29 18:37:29 UTC 2019 on sn-devel-144

and the last 50 lines of the stdout log were:

[196(3463)/226 at 31m10s] pidl.wireshark-ndr
[197(3503)/226 at 31m10s] tdb.python
[198(3557)/226 at 31m10s] samba.tests.dsdb_lock
[199(3564)/226 at 32m28s] samba.tests.samba_tool.visualize
[200(3575)/226 at 32m31s] samba.tests.samba_tool.provision_password_check
[201(3579)/226 at 32m40s] samba.tests.samba_tool.help
[202(3580)/226 at 33m44s] samba.tests.domain_backup_offline
[203(3584)/226 at 35m9s] samba.tests.lsa_string
[204(3588)/226 at 35m10s] samba.tests.loadparm
[205(3591)/226 at 35m10s] samba4.blackbox.samba3dump
[206(3592)/226 at 35m10s] samba4.blackbox.upgrade
[207(3600)/226 at 35m37s] samba4.blackbox.provision.py
[208(3607)/226 at 36m26s] samba4.blackbox.supported_features
[209(3613)/226 at 36m35s] samba4.blackbox.start_backup
[210(3616)/226 at 36m44s] samba4.blackbox.upgradeprovision.current
[211(3623)/226 at 37m51s] samba4.blackbox.setpassword.py
[212(3629)/226 at 38m2s] samba4.blackbox.newuser.py
[213(3640)/226 at 38m15s] samba4.blackbox.group.py
[214(3669)/226 at 38m36s] samba4.blackbox.provision-backend
[215(3673)/226 at 38m43s] samba4.blackbox.renamedc.sh
[216(3684)/226 at 39m6s] samba4.dsdb.samdb.ldb_modules.unique_object_sids
[217(3690)/226 at 39m6s] samba4.dsdb.samdb.ldb_modules.encrypted_secrets.tdb
[218(3705)/226 at 39m6s] samba4.dsdb.samdb.ldb_modules.encrypted_secrets.mdb
[219(3720)/226 at 39m7s] lib.audit_logging.audit_logging
[220(3735)/226 at 39m7s] lib.audit_logging.audit_logging.errors
[221(3749)/226 at 39m7s] samba4.dsdb.samdb.ldb_modules.audit_util
[222(3766)/226 at 39m7s] samba4.dsdb.samdb.ldb_modules.audit_log
[223(3788)/226 at 39m7s] samba4.dsdb.samdb.ldb_modules.audit_log.errors
[224(3793)/226 at 39m7s] samba4.dsdb.samdb.ldb_modules.group_audit
UNEXPECTED(failure): samba4.dsdb.samdb.ldb_modules.group_audit.test_audit_group_json_error(none)
REASON: Exception: Exception: time stamp "2019-03-30T10:01:56.000044+0000" is after finish time "2019-03-30T10:01:55"
../../source4/dsdb/samdb/ldb_modules/tests/test_group_audit.c:950: error: Failure!

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

A summary with detailed information can be found in:
  ./bin/ab/summary
TOP 10 slowest tests
samba.tests.docs -> 439
samba4.blackbox.upgradeprovision.alpha13 -> 175
samba4.blackbox.upgradeprovision.release-4-0-0 -> 144
samba4.blackbox.schemaupgrade -> 118
samba4.blackbox.dbcheck.release-4-0-0 -> 97
samba4.blackbox.dbcheck.release-4-0-0.quick -> 94
samba4.blackbox.dbcheck.release-4-1-0rc3 -> 89
samba4.blackbox.dbcheck.release-4-1-0rc3.quick -> 85
samba.tests.domain_backup_offline -> 85
samba.tests.dsdb_lock -> 77
ERROR: test failed with exit code 1
Makefile:16: recipe for target 'test' failed