Use of uninitialized value $ret in string eq at /usr/share/perl5/Debconf/FrontEnd/Passthrough.pm line 134.

[Sune TB Nielsen]

Some error message popped up. Everything seems normal still.

ProblemType: Package
DistroRelease: Ubuntu 20.10
Package: libpam-sss:amd64 2.3.1-3ubuntu3
ProcVersionSignature: Ubuntu 5.8.0-41.46-generic 5.8.18
Uname: Linux 5.8.0-41-generic x86_64
ApportVersion: 2.20.11-0ubuntu50.5
Architecture: amd64
CasperMD5CheckResult: skip
Date: Sat Feb 6 16:42:33 2021
DuplicateSignature:
 package:libpam-sss:amd64:2.3.1-3ubuntu3
 Setting up libpam-sss:amd64 (2.3.1-3ubuntu3) ...
 Use of uninitialized value $ret in string eq at /usr/share/perl5/Debconf/FrontEnd/Passthrough.pm line 134.
 dpkg: error processing package libpam-sss:amd64 (--configure):
  installed libpam-sss:amd64 package post-installation script subprocess returned error exit status 128
ErrorMessage: installed libpam-sss:amd64 package post-installation script subprocess returned error exit status 128
InstallationDate: Installed on 2020-12-14 (54 days ago)
InstallationMedia: Ubuntu 20.10 "Groovy Gorilla" - Release amd64 (20201022)
Python3Details: /usr/bin/python3.8, Python 3.8.6, python3-minimal, 3.8.6-0ubuntu1
PythonDetails: N/A
RelatedPackageVersions:
 dpkg 1.20.5ubuntu2
 apt 2.1.10ubuntu0.2
SourcePackage: sssd
Title: package libpam-sss:amd64 2.3.1-3ubuntu3 failed to install/upgrade: installed libpam-sss:amd64 package post-installation script subprocess returned error exit status 128
UpgradeStatus: No upgrade log present (probably fresh install)

[Bryce Harrington (bryce)]

From the log, looks like this hit a bug in debconf. Same issue appears to crop up for other packages (e.g. LP: #1914964).

 Setting up libpam-sss:amd64 (2.3.1-3ubuntu3) ...
 Use of uninitialized value $ret in string eq at /usr/share/perl5/Debconf/FrontEnd/Passthrough.pm line 134.

The code in question is:

sub capb
{
        my $this=shift;
        my $ret;
 return $this->{capb} if exists $this->{capb};

        ($ret, $this->{capb}) = $this->talk('CAPB');
 return $this->{capb} if $ret eq '0';
}

So apparently whatever $this->talk('CAPB') resolves to returned an undefined value for $ret. A paper-over fix might be something like:

 return $this->{capb} if defined $ret and $ret eq '0';

However, would be better to know what triggers the error condition since there could be a deeper problem involved.

Anyway, thanks for reporting this defect in Ubuntu, hopefully there's enough info for the debconf maintainers to take it from here.

[Launchpad Janitor (janitor)]

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