Unattended-upgrades may keep running after unmounting local filesystems in InstallOnShutdown mode

The fix is already released in 1.7ubuntu1.

Hello Balint, or anyone else affected,

Accepted unattended-upgrades into cosmic-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/unattended-upgrades/1.5ubuntu3.18.10.0 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-cosmic to verification-done-cosmic. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-cosmic. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

Verified with unattended-upgrades 1.5ubuntu3.18.10.0:

oot@cc-uu-onshutdown:~# service unattended-upgrades status
● unattended-upgrades.service - Unattended Upgrades Shutdown
   Loaded: loaded (/lib/systemd/system/unattended-upgrades.service; enabled; vendor preset: enabled)
   Active: active (running) since Tue 2018-11-27 22:05:20 UTC; 6s ago
     Docs: man:unattended-upgrade(8)
 Main PID: 2198 (unattended-upgr)
    Tasks: 2 (limit: 4915)
   Memory: 8.1M
   CGroup: /system.slice/unattended-upgrades.service
           └─2198 /usr/bin/python3 /usr/share/unattended-upgrades/unattended-upgrade-shutdown --wait-for-signal

Nov 27 22:05:20 cc-uu-onshutdown systemd[1]: Started Unattended Upgrades Shutdown.
root@cc-uu-onshutdown:~# vi /etc/apt/sources.list
root@cc-uu-onshutdown:~# echo 'Unattended-Upgrade::InstallOnShutdown "true";' > /etc/apt/apt.conf.d/51unattended-upgrades-on-shutdown
root@cc-uu-onshutdown:~# dbus-send --system --print-reply --dest=org.freedesktop.login1 /org/freedesktop/login1 "org.freedesktop.login1.Manager.Reboot" boolean:false
method return time=1543356364.788282 sender=:1.4 -> destination=:1.14 serial=32 reply_serial=2
root@cc-uu-onshutdown:~# logout
rbalint@yogi:~/tmp$ lxc shell cc-uu-onshutdown
mesg: ttyname failed: No such device
root@cc-uu-onshutdown:~# uptime
 22:06:50 up 0 min, 0 users, load average: 0.39, 0.44, 0.36
root@cc-uu-onshutdown:~# journalctl -l | grep -B5 -A5 Unatt
Nov 27 22:05:20 cc-uu-onshutdown systemd[1]: snapd.seeded.service: Failed to reset devices.list: Operation not permitted
Nov 27 22:05:20 cc-uu-onshutdown systemd[1]: systemd-user-sessions.service: Failed to reset devices.list: Operation not permitted
Nov 27 22:05:20 cc-uu-onshutdown systemd[1]: systemd-sysctl.service: Failed to reset devices.list: Operation not permitted
Nov 27 22:05:20 cc-uu-onshutdown systemd[1]: snap.mount: Failed to reset devices.list: Operation not permitted
Nov 27 22:05:20 cc-uu-onshutdown systemd[1]: unattended-upgrades.service: Failed to reset devices.list: Operation not permitted
Nov 27 22:05:20 cc-uu-onshutdown systemd[1]: Started Unattended Upgrades Shutdown.
Nov 27 22:06:06 cc-uu-onshutdown systemd-logind[190]: System is rebooting.
Nov 27 22:06:06 cc-uu-onshutdown systemd[1]: Stopping Availability of block devices...
Nov 27 22:06:06 cc-uu-onshutdown systemd[1]: Removed slice system-getty.slice.
Nov 27 22:06:06 cc-uu-onshutdown systemd[1]: Stopping Session c1 of user root.
Nov 27 22:06:06 cc-uu-onshutdown su[1160]: pam_unix(su:session): session closed for user root
--
...
root@cc-uu-onshutdown:~# cat /var/log/unattended-upgrades/unattended-upgrades
unattended-upgrades-dpkg.log unattended-upgrades-shutdown.log unattended-upgrades.log
root@cc-uu-onshutdown:~# cat /var/log/unattended-upgrades/unattended-upgrades-shutdown.log
2018-11-27 22:06:04,792 WARNING - Running unattended-upgrades in shutdown mode
2018-11-27 22:06:04,804 WARNING - Unattended-upgrade in progress during shutdown, please don't turn off the computer
2018-11-27 22:06:06,457 WARNING - Unattended-upgrade in progress during shutdown, please don't turn off the computer
2018-11-27 22:06:06,473 INFO - All upgrades installed
root@cc-uu-onshutd...

This bug was fixed in the package unattended-upgrades - 1.5ubuntu3.18.10.0

---------------
unattended-upgrades (1.5ubuntu3.18.10.0) cosmic; urgency=medium

  * Revert to running unattended-upgrades.service in multi-user.target
  * Trigger unattended-upgrade-shutdown actions with PrepareForShutdown()
    Performing upgrades in service's ExecStop did not work when the upgrades
    involved restarting services because systemd blocked other stop/start
    actions making maintainer scripts time out and be killed leaving a broken
    system behind.
    Running unattended-upgrades.service before shutdown.target as a oneshot
    service made it run after unmounting filesystems and scheduling services
    properly on shutdown is a complex problem and adding more services to the
    mix make it even more fragile.
    The solution of monitoring PrepareForShutdown() signal from DBus
    allows Unattended Upgrade to run _before_ the jobs related to shutdown are
    queued thus package upgrades can safely restart services without
    risking causing deadlocks or breaking part of the shutdown actions.
    Also ask running unattended-upgrades to stop when shutdown starts even in
    InstallOnShutdown mode and refactor most of unattended-upgrade-shutdown to
    UnattendedUpgradesShutdown class. (LP: #1778219, LP: #1803137)
  * Handle reverting to WantedBy=multi-user.target
  * Increase logind's InhibitDelayMaxSec to 30s.
    This allows more time for unattended-upgrades to shut down gracefully
    or even install a few packages in InstallOnShutdown mode, but is still a
    big step back from the 30 minutes allowed for InstallOnShutdown previously.
    Users enabling InstallOnShutdown mode are advised to increase
    InhibitDelayMaxSec even further possibly to 30 minutes.
  * Cache polling result for PreparingForShutdown after it becomes true
  * debian/tests/test-systemd.py: Reboot system with dbus call to honor
    inhibitor locks
  * Add NEWS entry about increasing InhibitDelayMaxSec and InstallOnShutdown
    changes
  * Stop using ActionGroups, they interfere with apt.Cache.clear()
    causing all autoremovable packages to be handled as newly autoremovable ones
    and be removed by default. Dropping ActionGroup usage does not slow down the
    most frequent case of not having anything to upgrade and when ther are
    packages to upgrade the gain is small compared to the actual package
    installation.
    Also collect autoremovable packages before adjusting candidates because that
    also changed .is_auto_removable attribute of some of them. (LP: #1803749)
    (Closes: #910874)

 -- Balint Reczey <email address hidden> Mon, 26 Nov 2018 12:28:55 +0100

The verification of the Stable Release Update for unattended-upgrades has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.