[Bug 1900390] Re: do-release-update hangs from use of user $PATH (specifically 'npm which')

[Brian Murray]

** Tags removed: rls-ff-incoming

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to ubuntu-release-upgrader in
Ubuntu.
https://bugs.launchpad.net/bugs/1900390

Title:
  do-release-update hangs from use of user $PATH (specifically 'npm
  which')

Status in ubuntu-release-upgrader package in Ubuntu:
  New

Bug description:
  When I updated from 18.04 to 20.04 with do-release-upgrade,
  I noticed that the cups package prerm script would hang forever.
  After I hit ctrl-C, it was fairly messy to fix the system back together.

  When I traced this, I found that `which` in the prerm script
  (and not just cups but potentially all of them?) resolved to
  /usr/local/bin/which from my $PATH, which was from the npm `which` package.
  I don't really understand how even `npm which` could hang, but it did somehow.

  Everything worked again after I deleted npm `which`.

  The lesson here seems to be that do-release-upgrade should restrict $PATH
  so that these kinds of problems can't happen.

  This is a possible problem for apt in general, but it's more problematic for do-release-update
  since it could not be rolled back in this case.

  ProblemType: Bug
  DistroRelease: Ubuntu 20.04
  Package: ubuntu-release-upgrader-core 1:20.04.28
  ProcVersionSignature: Ubuntu 5.4.0-51.56-generic 5.4.65
  Uname: Linux 5.4.0-51-generic x86_64
  NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair nvidia_modeset nvidia
  ApportVersion: 2.20.11-0ubuntu27.9
  Architecture: amd64
  CasperMD5CheckResult: skip
  CrashDB: ubuntu
  Date: Mon Oct 19 10:12:55 2020
  InstallationDate: Installed on 2018-11-13 (706 days ago)
  InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
  PackageArchitecture: all
  SourcePackage: ubuntu-release-upgrader
  Symptom: release-upgrade
  UpgradeStatus: Upgraded to focal on 2020-10-17 (1 days ago)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1900390/+subscriptions