Bug#923983: dahdi-dkms: prerm fails if module was not on the system at remove time

[Tzafrir Cohen]

Package: dahdi-dkms
Version: 1:2.11.1.0.20170917~dfsg-5
Severity: important


dahdi-dkms includes packaging from an patch from Ubuntu. It seems that
the Debian packaging has since become more robust.

The package has included its own postinst and prerm scripts and did not
use the ones provided by dh_dkms.

Specifically, if the package does not install the module at postinst
(e.g. because it is a container running on a different kernel) or if
it was manually removed before the package was removed, the prerm
script doesn't check. It tries to remove, fails, and gives an error.

This has caused the failure of puiparts (but only after a newer version
was uploaded:

https://piuparts.debian.org/sid/fail/dahdi-linux_1:2.11.1.0.20170917~dfsg-6.log

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.19.0-2-amd64 (SMP w/4 CPU cores)
Kernel taint flags: TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_IL, LC_CTYPE=en_IL (charmap=UTF-8), LANGUAGE=en_IL:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages dahdi-dkms depends on:
ii  dkms       2.6.1-4
ii  dpkg-dev   1.19.5
ii  gawk       1:4.2.1+dfsg-1
ii  gcc        4:8.2.0-2
ii  libc6-dev  2.28-7
ii  make       4.2.1-1.2
ii  wget       1.20.1-1

Versions of packages dahdi-dkms recommends:
ii  dahdi-linux  1:2.11.1.0.20170917~dfsg-5

dahdi-dkms suggests no packages.

-- no debconf information