A somewhat similar issue was observed with libcomps by Redhat users:

https://bugzilla.redhat.com/show_bug.cgi?id=1734777#c3
https://github.com/rpm-software-management/libcomps/pull/50

A quote from the latter link:

In Python 3.7, import didn't check descriptor flags (METH_KEYWORDS):
these flags were only checked when the methods were called.

In Python 3.8, the flags are checked at soon as the module is
imported, which prevents the module to be imported.

As reported in https://bugs.archlinux.org/index.php?do=details&action=details.addvote&task_id=64537 downgrading to Python 3.7 resolves the issue. Therefore it appears likely that checking flags immediately at the module import in Python 3.8 can be the root cause of the issue.

Created attachment 15660 [details]
patch in the missing METH_VARARGS

Thanks Val for the report and your work identifying the problem.

I think this patch should fix it.

I guess this will need backporting to 4.10 and 4.11.

Created attachment 15665 [details]
patch for 4.10

Created attachment 15666 [details]
patch for 4.11

Val Kulkov: are you able to confirm this patch works?

The patch for 4.10 is different from the others due to formatting changes.

Douglas, until 2019-Dec-09 I will be unable to do anything unfortunately. Even after 2019-12-09 it may take a few days for me to confirm that the patch works. I am going to contact the maintainer of "samba" package on Arch Linux to see if they can do something in the interim.

Assigning to Karolin for the next available releases.

Created attachment 15673 [details]
Proposed patch for pygensec.c

Fix missing method type

The patch in Comment 2 is not enough; samba-tool fails with:

ERROR(<class 'SystemError'>): uncaught exception - bad call flags
  File "bin/samba-tool", line 44, in <module>
    retval = cmd._run("samba-tool", subcommand, *args)
  File "bin/python/samba/netcmd/__init__.py", line 256, in _run
    cmd = self.subcommands[cmd_name]
  File "bin/python/samba/netcmd/main.py", line 35, in __getitem__
    self[attr] = getattr(__import__('samba.netcmd.%s' % package,
  File "bin/python/samba/netcmd/domain.py", line 44, in <module>
    from samba.join import join_RODC, join_DC, join_subdomain
  File "bin/python/samba/join.py", line 24, in <module>
    from samba import gensec, Ldb, drs_utils, arcfour_encrypt, string_to_byte_array

However, adding the patch in Comment 9 appears to fix the problem, at least in my case. Thanks Douglas and Torsten.

Torsten,

Thank you!

Would you be able to attach a version of your patch with a commit message containing a "Signed-off-by:" line (using roughly `git add -p; git commit -s; git format-patch HEAD^`).

Also please decide whether you need to send in a developers certificate of origin, per https://www.samba.org/samba/devel/copyright-policy.html

Created attachment 15683 [details]
pygensec.c patch

Signed Off/from git master

https://bugzilla.samba.org/attachment.cgi?id=15683 lgtm. Pushed to autobuild.

No backporting to 4.10 and 4.11?

Created attachment 15707 [details]
pygensec patch for 4.11

Created attachment 15709 [details]
pygensec patch for 4.10

pygensec patch for 4.10

G'Day Karolin,

Please push both the original and pygensec patches to 4.10 and 4.11.

Thanks!

Created attachment 15710 [details]
pygensec patch for 4.10 v2 (added BUG: line)

Created attachment 15711 [details]
pygensec patch for 4.11 v2 (added BUG: line)

Val: our process involves getting the patches into master before generating backports so that we can cross-reference with the master commit id.

(Our process also sometimes involves forgetting to do this, so thanks for the reminder).

Comment on attachment 15710 [details]
pygensec patch for 4.10 v2 (added BUG: line)

Thanks for the BUG line.

(In reply to Andrew Bartlett from comment #17)
Pushed both patches to autobuild-v4-{11,10}-test.

(In reply to Karolin Seeger from comment #21)
Pushed to both branches.
Closing out bug report.

Thanks!