libpam-moudles update failure

[Jacob Jiahao Xu]

today ubuntu software updater pushed a update, but it failed when update libpam-modules from 1.3.1-5ubuntu4.1 to 1.3.1-5ubuntu4.1.

after that i tried to update this package manually, here is the error reported.

debconf: DbDriver "config": /var/cache/debconf/config.dat is locked by another process: Resource temporarily unavailable
(Reading database ... 187403 files and directories currently installed.)
Preparing to unpack .../libpam-modules_1.3.1-5ubuntu4.1_amd64.deb ...
debconf: DbDriver "config": /var/cache/debconf/config.dat is locked by another p
rocess: Resource temporarily unavailable
dpkg: error processing archive /var/cache/apt/archives/libpam-modules_1.3.1-5ubu
ntu4.1_amd64.deb (--unpack):
 new libpam-modules:amd64 package pre-installation script subprocess returned er
ror exit status 1
Errors were encountered while processing:
 /var/cache/apt/archives/libpam-modules_1.3.1-5ubuntu4.1_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

seems caused by debconf, similar to the bug below:

https://bugs.launchpad.net/ubuntu/+source/libgtk3-perl/+bug/1871960

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: libpam-modules 1.3.1-5ubuntu4
ProcVersionSignature: Ubuntu 5.4.0-45.49-generic 5.4.55
Uname: Linux 5.4.0-45-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.8
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Thu Sep 3 17:34:21 2020
InstallationDate: Installed on 2020-08-18 (16 days ago)
InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: pam
UpgradeStatus: No upgrade log present (probably fresh install)

[Jacob Jiahao Xu (jhsyu)]

$ sudo lsof /var/cache/debconf/config.dat
$ sudo kill [pid listed above]

then update is successful.

[Steve Langasek (vorlon)]

Since your debconf database was locked but dpkg and apt were not, this is not a bug in the pam package; and since you say you've killed the process that held the lock, there's not much more debugging we can do. Therefore, closing this bug report as invalid.