package ufw 0.36-6 failed to install/upgrade: end of file on stdin at conffile prompt

[Edward Savage]

No action on my part resulted in a report problem dialog. I have never modified the ufw configuration through the life of this install, which has come from 18.04 thru 19.04 and 19.10 to arrive at 20.04. Guessing someone made a typo in packaging.

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: ufw 0.36-6
ProcVersionSignature: Ubuntu 5.4.0-21.25-generic 5.4.27
Uname: Linux 5.4.0-21-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu24
AptOrdering:
 ufw:amd64: Install
 NULL: ConfigurePending
Architecture: amd64
Date: Tue Apr 7 06:45:08 2020
ErrorMessage: end of file on stdin at conffile prompt
InstallationDate: Installed on 2017-04-14 (1088 days ago)
InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
PackageArchitecture: all
Python3Details: /usr/bin/python3.8, Python 3.8.2, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.17, python-is-python2, 2.7.17-3
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.1
SourcePackage: ufw
Title: package ufw 0.36-6 failed to install/upgrade: end of file on stdin at conffile prompt
UpgradeStatus: Upgraded to focal on 2020-04-06 (0 days ago)
mtime.conffile..etc.default.ufw: 2019-07-28T20:35:23.745568

[Jamie Strandboge (jdstrand)]

Thank you for reporting a bug and helping to make Ubuntu better.

Based on https://launchpadlibrarian.net/473334677/DpkgTerminalLog.txt:

Preparing to unpack .../archives/ufw_0.36-6_all.deb ...
Unpacking ufw (0.36-6) over (0.36-5) ...
Setting up ufw (0.36-6) ...

Configuration file '/etc/default/ufw'
 ==> Modified (by you or by a script) since installation.
 ==> Package distributor has shipped an updated version.
   What would you like to do about it ? Your options are:
    Y or I : install the package maintainer's version
    N or O : keep your currently-installed version
      D : show the differences between the versions
      Z : start a shell to examine the situation
 The default action is to keep your current version.
*** ufw (Y/I/N/O/D/Z) [default=N] ? dpkg: error processing package ufw (--configure):
 end of file on stdin at conffile prompt

Looking at https://launchpadlibrarian.net/473334680/modified.conffile..etc.default.ufw.txt I can see that the file (/etc/default/ufw) is missing the trailing newline from 0.36-5 (this file is not manipulated by the ufw command).

I can't say why the file on your system was missing the trailing newline, but since it was, unattended-upgrades (seen in https://launchpadlibrarian.net/473334676/DpkgHistoryLog.txt) wasn't in a position to answer the conffile question.

This is not a bug in ufw. To remedy the situation, you should be able to perform: sudo apt-get -f install.

I also see that the system is running the current development release of Ubuntu. Unlike stable releases of Ubuntu, it is sometimes easier to disable unattended-upgrades when using the development release and instead run apt manually. If you disable it, feel free to re-enable it once Ubuntu 20.04 is released.

Thanks again!

[Edward Savage (epssyis)]

All good, thanks Jamie.

[Balint Reczey (rbalint)]

I tried reproducing the issue with u-u 2.1 and it detected the changed configuration file when I downgraded to ufw 0.36-5 and copied the attached config file over the shipped one.

There may be something else going on the system causing u-u not detecting the difference.