gdm3 self-enables during upgrade

[Nick]

I've been running Ubuntu 20.04 LTS on some servers for a while. This week, they started going non-responsive. Plugging in monitors and keyboards to them, I found they had gone to sleep, and waking them up showed the purple gdm login screen. Before, they've always just had my good friend getty showing a black and white "login: " prompt.

Watching their behaviour for about an hour, I found the suspends were happening at 20 minute intervals, which is gdm's default sleep timer, so I'm reasonably confident my downtime problem was because gdm had self-activated unexpectedly.

I checked my logs and found that unattended-upgrades had installed a new version overnight. I'd never noticed I even had gdm3 installed because it was never active before, and I'm still working out why that is, and I've disabled and purged it, but regardless I am surprised that the upgrade self-activated it like that without my consent.

I would like to ask that gdm3's configure script takes account of the current `service enable`/`service disable`/`systemctl enable`/`systemctl disable` state, if it's not already doing that. Or, just don't touch `service` at all during an upgrade. During an install is fine, but please not during an upgrade.

Here's version details from the two servers I've seen this on so far:

root@romane:~# lsb_release -rd
Description: Ubuntu 20.04.3 LTS
Release: 20.04
root@romane:~# apt-cache policy gdm3
gdm3:
  Installed: (none)
  Candidate: 3.36.3-0ubuntu0.20.04.4
  Version table:
     3.36.3-0ubuntu0.20.04.4 500
        500 http://ca.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
     3.36.3-0ubuntu0.20.04.2 500
        500 http://ca.archive.ubuntu.com/ubuntu focal-security/main amd64 Packages
     3.34.1-1ubuntu1 500
        500 http://ca.archive.ubuntu.com/ubuntu focal/main amd64 Packages

root@rosenberg:~# lsb_release -rd
Description: Ubuntu 20.04.3 LTS
Release: 20.04
root@rosenberg:~# apt-cache policy gdm3
gdm3:
  Installed: 3.36.3-0ubuntu0.20.04.4
  Candidate: 3.36.3-0ubuntu0.20.04.4
  Version table:
 *** 3.36.3-0ubuntu0.20.04.4 500
        500 http://ca.archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     3.36.3-0ubuntu0.20.04.2 500
        500 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages
     3.34.1-1ubuntu1 500
        500 http://ca.archive.ubuntu.com/ubuntu focal/main amd64 Packages

Here's the relevant upgrade logs from the two:

root@romane:~# grep 2022-02-10 /var/log/dpkg.log | grep gdm3
2022-02-10 06:22:56 install gdm3:amd64 3.36.3-0ubuntu0.20.04.3 3.36.3-0ubuntu0.20.04.4
2022-02-10 06:22:56 status half-installed gdm3:amd64 3.36.3-0ubuntu0.20.04.3
2022-02-10 06:22:56 status unpacked gdm3:amd64 3.36.3-0ubuntu0.20.04.4
2022-02-10 06:25:01 configure gdm3:amd64 3.36.3-0ubuntu0.20.04.4 <none>
2022-02-10 06:25:01 status unpacked gdm3:amd64 3.36.3-0ubuntu0.20.04.4
2022-02-10 06:25:01 status half-configured gdm3:amd64 3.36.3-0ubuntu0.20.04.4
2022-02-10 06:25:02 status installed gdm3:amd64 3.36.3-0ubuntu0.20.04.4

root@rosenberg:~# grep 2022-02-13 /var/log/dpkg.log | grep gdm3
2022-02-13 06:08:05 install gdm3:amd64 <none> 3.36.3-0ubuntu0.20.04.4
2022-02-13 06:08:05 status half-installed gdm3:amd64 3.36.3-0ubuntu0.20.04.4
2022-02-13 06:08:06 status unpacked gdm3:amd64 3.36.3-0ubuntu0.20.04.4
2022-02-13 06:11:52 configure gdm3:amd64 3.36.3-0ubuntu0.20.04.4 <none>
2022-02-13 06:11:52 status unpacked gdm3:amd64 3.36.3-0ubuntu0.20.04.4
2022-02-13 06:11:52 status half-configured gdm3:amd64 3.36.3-0ubuntu0.20.04.4
2022-02-13 06:11:53 status installed gdm3:amd64 3.36.3-0ubuntu0.20.04.4

[Nick (kousu)]

Oh also maybe this would be handy, I use etckeeper(8) with unattended-upgrades(8) so I can show you that the change happened when gdm went from 3.36.3-0ubuntu0.20.04.3 -> 3.36.3-0ubuntu0.20.04.4:

root@romane:~# etckeeper vcs log fea52b81f4bbc9c171206a56a4d53087bf82b82d~..fea52b81f4bbc9c171206a56a4d53087bf82b82d
commit fea52b81f4bbc9c171206a56a4d53087bf82b82d
Author: root <root@romane>
Date: Thu Feb 10 06:25:28 2022 -0500

    committing changes in /etc made by "/usr/bin/python3 /usr/bin/unattended-upgrade"

    Package changes:
    +aptdaemon-data 1.1.1+bzr982-0ubuntu32.3 all
    -avahi-daemon 0.7-4ubuntu7 amd64
    +avahi-daemon 0.7-4ubuntu7.1 amd64
    +avahi-utils 0.7-4ubuntu7.1 amd64
    -bluez 5.53-0ubuntu3.1 amd64
    +bluez 5.53-0ubuntu3.5 amd64
    +cheese-common 3.34.0-1ubuntu1 all
    +colord-data 1.4.4-2 all
    +dconf-cli 0.36.0-1 amd64
    -evolution-data-server 3.36.4-0ubuntu1 amd64
    +evolution-data-server 3.36.5-0ubuntu1 amd64
    +evolution-data-server-common 3.36.5-0ubuntu1 all
    -fprintd 1.90.1-1ubuntu1 amd64
    +fprintd 1.90.9-1~ubuntu20.04.1 amd64
    +gcr 3.36.0-2build1 amd64
    -gdm3 3.36.3-0ubuntu0.20.04.3 amd64
    +gdm3 3.36.3-0ubuntu0.20.04.4 amd64
    +gir1.2-accountsservice-1.0 0.6.55-0ubuntu12~20.04.5 amd64
    +gir1.2-atk-1.0 2.35.1-1ubuntu2 amd64
    +gir1.2-atspi-2.0 2.36.0-2 amd64
    +gir1.2-freedesktop 1.64.1-1~ubuntu20.04.1 amd64
    +gir1.2-gck-1 3.36.0-2build1 amd64
    +gir1.2-gcr-3 3.36.0-2build1 amd64
    +gir1.2-gdesktopenums-3.0 3.36.0-1ubuntu1 amd64
    +gir1.2-gdkpixbuf-2.0 2.40.0+dfsg-3ubuntu0.2 amd64
    +gir1.2-gdm-1.0 3.36.3-0ubuntu0.20.04.4 amd64
    +gir1.2-geoclue-2.0 2.5.6-0ubuntu1 amd64
    +gir1.2-gnomebluetooth-1.0 3.34.3-0ubuntu1 amd64
    +gir1.2-gnomedesktop-3.0 3.36.8-0ubuntu1 amd64
    +gir1.2-graphene-1.0 1.10.0-1build2 amd64
    +gir1.2-gtk-3.0 3.24.20-0ubuntu1 amd64
    +gir1.2-gweather-3.0 3.36.1-1~ubuntu20.04.1 amd64
    +gir1.2-ibus-1.0 1.5.22-2ubuntu2.1 amd64
    +gir1.2-json-1.0 1.4.4-2ubuntu2 amd64
    +gir1.2-mutter-6 3.36.9-0ubuntu0.20.04.2 amd64
    +gir1.2-nm-1.0 1.22.10-1ubuntu2.3 amd64
    +gir1.2-nma-1.0 1.8.24-1ubuntu3 amd64
    +gir1.2-notify-0.7 0.7.9-1ubuntu2 amd64
    +gir1.2-packagekitglib-1.0 1.1.13-2ubuntu1.1 amd64
    +gir1.2-pango-1.0 1.44.7-2ubuntu4 amd64
    +gir1.2-polkit-1.0 0.105-26ubuntu1.2 amd64
    +gir1.2-rsvg-2.0 2.48.9-1ubuntu0.20.04.1 amd64
    +gir1.2-secret-1 0.20.4-0ubuntu1 amd64
    +gir1.2-soup-2.4 2.70.0-1 amd64
    +gir1.2-upowerglib-1.0 0.99.11-1build2 amd64
    +gir1.2-vte-2.91 0.60.3-0ubuntu1~20.04 amd64
    +gjs 1.64.5-0ubuntu0.20.04.01 amd64
    +gkbd-capplet 3.26.1-1 amd64
    -gnome-control-center-data 1:3.36.5-0ubuntu1 all
    +gnome-control-center 1:3.36.5-0ubuntu3 amd64
    +gnome-control-center-data 1:3.36.5-0ubuntu3 all
    +gnome-control-center-faces 1:3.36.5-0ubuntu3 all
    +gnome-desktop3-data 3.36.8-0ubuntu1 all
    +gnome-keyring-pkcs11 3.36.0-1ubuntu1 amd64
    +gnome-online-accounts 3.36.1-0ubuntu1 amd64
    +gnome-session-bin 3.36.0-2ubuntu1 amd64
    -gnome-settings-daemon 3.36.1-0ubuntu1 amd64
    -gnome-shell 3.36.7-0ubuntu0.20.04.1 amd64
    +gnome-settings-daemon 3.36.1-0ubuntu1.1 amd64
    +gnome-s...

[Chris Guiver (guiverc)]

Thank you for taking the time to report this bug and helping to make Ubuntu better.

Bug reporting is mostly about finding & fixing problems thus preventing future users from hitting the same bug.

I suspect a Support site would be more appropriate, eg. https://answers.launchpad.net/ubuntu. You can also find help with your problem in the support forum of your local Ubuntu community http://loco.ubuntu.com/ or asking at https://askubuntu.com or https://ubuntuforums.org, or for more support options please look at https://discourse.ubuntu.com/t/community-support/709

Ubuntu Servers don't have GNOME or `gdm3` installed as they are desktop packages. Your issue appears to have occurred because of packages added to your system, thus you'd benefit more from support I suspect.

Please execute the following command only once, as it will automatically gather debugging information, in a terminal:

apport-collect 1960857

When reporting bugs in the future please use apport by using 'ubuntu-bug' and the name of the package affected. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.