do-release-upgrade crashes after twice "Calculating the changes"

[Lupe Christoph]

$ lsb_release -rd
No LSB modules are available.
Description: Ubuntu 23.10
Release: 23.10

$ apt-cache policy ubuntu-release-upgrader-core
ubuntu-release-upgrader-core:
  Installed: 1:23.10.14
  Candidate: 1:23.10.14

For completeness sake: I expected a system using Noble, but got a crash instead ;-)

I ran this on an installation of Ubuntu server and it ran OK. So this may be because the crash happened on a system that has been upgraded about two dozen times (I lost track). Or because it has many packages that may be long obsolete or not needed anymore. The Ubuntu server installation is only four months old.

do-release-upgrade exits after printing "Calculating the changes" twice, the last gasp was "=== Command terminated with exit status 1 (Sun May 26 22:24:00 2024) ===".

I'm attaching /var/log/dist-upgrade/screenlog.0

I ran strace -f on do-release-upgrade and found that it crashes in /tmp/ubuntu-release-upgrader-cn6qkutf/noble which is a trivial Python program. The cause is this:

Error in sys.excepthook:
Traceback (most recent call last):
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeViewText.py", line 138, in _handleException
    apport_crash(type, value, tb)
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeApport.py", line 57, in apport_crash
    apport_excepthook(type, value, tb)
TypeError: apport_excepthook() missing 1 required positional argument: 'exc_tb'

Original exception was:
Traceback (most recent call last):
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/noble", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeMain.py", line 241, in main
    if app.run():
       ^^^^^^^^^
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeController.py", line 2607, in run
    return self.fullUpgrade()
           ^^^^^^^^^^^^^^^^^^
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeController.py", line 2504, in fullUpgrade
    if not self.askDistUpgrade():
           ^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeController.py", line 1662, in askDistUpgrade
    changes = self.calcDistUpgrade()
              ^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeController.py", line 1625, in calcDistUpgrade
    if not self.cache.distUpgrade(self._view, self.serverMode, self._partialUpgrade):
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeCache.py", line 243, in wrapper
    res = f(*args, **kwargs)
          ^^^^^^^^^^^^^^^^^^
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeCache.py", line 626, in distUpgrade
    self.pre_upgrade_rule()
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeCache.py", line 497, in pre_upgrade_rule
    self.quirks.run("PreDistUpgradeCache")
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeQuirks.py", line 95, in run
    func()
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeQuirks.py", line 191, in PreDistUpgradeCache
    self._install_t64_replacement_packages()
  File "/tmp/ubuntu-release-upgrader-cn6qkutf/DistUpgrade/DistUpgradeQuirks.py", line 1845, in _install_t64_replacement_packages
    if replacement.candidate._cand != ver:
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute '_cand'

No idea what causes this problem.

ProblemType: Bug
DistroRelease: Ubuntu 23.10
Package: ubuntu-release-upgrader-core 1:23.10.14
ProcVersionSignature: Ubuntu 6.5.0-35.35-generic 6.5.13
Uname: Linux 6.5.0-35-generic x86_64
ApportVersion: 2.27.0-0ubuntu5
Architecture: amd64
CasperMD5CheckResult: unknown
CrashDB: ubuntu
CrashReports:
 640:1000:117:753042:2024-05-26 15:21:54.992012633 +0200:2024-05-26 15:21:52.448320617 +0200:/var/crash/_usr_bin_light-locker.1000.crash
 640:1000:117:13018108:2024-05-26 15:48:54.570569142 +0200:2024-05-26 15:48:51.110504695 +0200:/var/crash/_opt_SchildiChat_schildichat-desktop.1000.crash
 600:109:117:37:2024-05-23 22:59:03.459738210 +0200:2024-05-25 13:40:59.531724317 +0200:/var/crash/_usr_bin_fwbuilder.1000.uploaded
 664:1000:1000:0:2024-05-23 21:49:47.188695597 +0200:2024-05-23 21:49:47.188695597 +0200:/var/crash/_usr_bin_fwbuilder.1000.upload
 640:1000:117:15449568:2024-05-23 21:49:36.116516828 +0200:2024-05-25 13:40:59.487723528 +0200:/var/crash/_usr_bin_fwbuilder.1000.crash
CurrentDesktop: KDE
Date: Sun May 26 22:49:12 2024
InstallationDate: Installed on 2014-12-22 (3443 days ago)
InstallationMedia: Kubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to mantic on 2024-05-26 (0 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Javier Martin (Habbit) (habbit)]

I think this is the same issue in #2067071, reported a couple of days earlier, although this one has more complete logs, so maybe we should keep this one instead?