We have tried the extra kernel postinst script and it doesn't seem to
function appropriately.

The core issue for us is that our organization monitors our servers
using Qualys, and Qualys reads the kernel version on disk.  Qualys isn't
intelligent enough to know that Livepatch has patched the running
kernel.  So Qualys ends up flagging all of our servers as having
critical vulnerabilities (again, because it only checks the kernel
version on disk), even though technically the vulnerability has been
patched in the running kernel.  It is very frustrating to have to try
and explain to our central security team that the Qualys results are a
false positive every time this happens and we are contacted about it.

We are an Ubuntu Pro customer and we did open a ticket about this in
January 2025, but no ETA is available regarding this bug, sadly.   We
hope that Canonical starts working on this situation soon.   We would
rather not disable Livepatch, but given comments above, it seems like
the corporate view at Canonical is that we should disable it because
(according to them) we are not getting any value from it.

-- 
You received this bug notification because you are a member of Ubuntu
Touch seeded packages, which is subscribed to unattended-upgrades in
Ubuntu.
https://bugs.launchpad.net/bugs/2017401

Title:
  Unexpected / unwanted unattended-upgrades behaviour after kernel
  upgrade when Livepatch enabled

Status in unattended-upgrades package in Ubuntu:
  Confirmed
Status in unattended-upgrades source package in Focal:
  Confirmed
Status in unattended-upgrades source package in Jammy:
  Confirmed

Bug description:
  Following the resolution for bug #1747499, after a kernel upgrade when
  Livepatch is enabled, the current behaviour in unattended-upgrades
  (2.3ubuntu0.2 and later) is not to touch /var/run/reboot-required so
  as not to confuse users with two separate messages calling for a
  restart in motd. This functionality is implemented in the script at
  /etc/kernel/postinst.d/unattended-upgrades.

  While this works as intended in terms of suppressing an extra message
  in motd, it defeats the ability of unattended-upgrades to restart
  automatically with the new kernel, which is reliant on
  /var/run/reboot-required being present.

  This is unexpected / unwanted behaviour in scenarios where a)
  Livepatch is being used to provide fast-response kernel patching; and
  b) Unattended-Upgrade::Automatic-Reboot is set to true, to enable
  automatic reboots during a regular maintenance window. In this case,
  without administrative intervention, the system could never boot into
  the new kernel even though it would be expected to, leaving Livepatch
  to do all the heavy lifting indefinitely, and unnecessarily.

  I believe this counts as a regression caused by the resolution to bug
  #1747499. It also has the potential to be a security threat if
  Livepatch doesn't work comprehensively for a particular kernel flaw,
  and an administrator is reliant on expected behaviour according to
  unattended-upgrades settings.

  Potential options for a fix that come to mind:
  1. Revert to original behaviour in 
/etc/kernel/postinst.d/unattended-upgrades, and change the ***System restart 
required*** message to be less alarming or confusing when the cause is a kernel 
upgrade that's being patched by Livepatch.
  2. Add an extra configuration setting (eg 
Unattended-Upgrade::Automatic-Reboot-After-Livepatch) that triggers a reboot 
when it's 'recommended' by Livepatch, not reliant on the presence of 
/var/run/reboot-required.
  3. Add support in /etc/kernel/postinst.d/unattended-upgrades for an extra 
file somewhere. When present, /var/run/reboot-required is always touched, even 
if Livepatch is enabled.

  (This is my first time reporting a bug in this system, and I apologise
  if I haven't followed the usual descriptive format.)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/unattended-upgrades/+bug/2017401/+subscriptions


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