[debian-mysql] Bug#1022994: TMPDIR behaviour in maintainer scripts [was: Re: Bug#1023778: mysql-server-8.0: fails to restart on upgrade with libpam-tmpdir]

[Otto Kekäläinen]

> > I think the answer to this should probably be established by the
> > libpam-tmpdir maintainer and documented first, for fear of someone else
> > later coming along and saying that the maintainer script incorrectly
> > ignores TMPDIR because we started ignoring it to resolve this bug. So I
> > copied debian-devel@ for comment.
>
> I'm not sure this is libpam-tmpdir specific, but rather a bit more
> general: what are the expectations that maintainer scripts can have
> about the environment they're running in, and how do we make those
> expectations hold?  This should probably then be documented in policy.

This MySQL 8.0 in Sid tmpdir issue is identical to MariaDB 10.6 in Sid
tmpdir issue, as they are based on historically the same maintainer
script.

MariaDB duplicate of this has been filed as
https://jira.mariadb.org/browse/MDEV-29910 and
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1022994

The suggested solution in
https://salsa.debian.org/mariadb-team/mariadb-server/-/merge_requests/23
to set an empty TMPDIR does not seem to work - or at least CI shows
that even a basic install fails after that.

Instead of manually trying to manage TMPDIR env variable in various
places, we should have a standardized way to run maintainer scripts in
clean shell sessions that have all env variables set automatically
correctly.

More proposals on how to handle this are welcome at
https://salsa.debian.org/mariadb-team/mariadb-server/-/merge_requests
:)

- Otto