mjhjmtu

I had a bad crash (power outage while running apt upgrade) that left my system (a VirtualBox VM running Linux Mint.19, actually; host is an up-to-date Debian Sid, if it matters) in a very strange state:

System is apparently working properly (beside the apt/dpkg suite)

I had to reset apt:

mcon@mint:~$ sudo dpkg --configure -a
dpkg: dependency problems prevent configuration of linux-generic:
 linux-generic depends on linux-headers-generic (= 4.15.0.39.41); however:
 Version of linux-headers-generic on system is 4.15.0.38.40.

dpkg: error processing package linux-generic (--configure):
 dependency problems - leaving unconfigured
Errors were encountered while processing:
 linux-generic
mcon@mint:~$ 

After this I tried to restart apt:

mcon@mint:~$ sudo apt upgrade
Reading package lists... Done
Building dependency tree 
Reading state information... Done
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies:
 linux-generic : Depends: linux-headers-generic (= 4.15.0.39.41) but 4.15.0.38.40 is installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).
mcon@mint:~$ 

This is expected, but the command (actually sudo apt install --fix-broken, the command as printed is invalid) enters an infinite loop and blocks forever (with constant disk activity!):

mcon@mint:~$ sudo apt install -f
Reading package lists... Done
Building dependency tree 
Reading state information... Done
Correcting dependencies... Done
The following additional packages will be installed:
 linux-headers-4.15.0-39 linux-headers-4.15.0-39-generic
 linux-headers-generic
The following NEW packages will be installed:
 linux-headers-4.15.0-39-generic
The following packages will be upgraded:
 linux-headers-4.15.0-39 linux-headers-generic
2 upgraded, 1 newly installed, 0 to remove and 1 not upgraded.
2 not fully installed or removed.
Need to get 0 B/12,1 MB of archives.
After this operation, 89,9 MB of additional disk space will be used.
Do you want to continue? [Y/n] 
(Reading database ... 283441 files and directories currently installed.)
Preparing to unpack .../linux-headers-4.15.0-39_4.15.0-39.42_all.deb ...
Unpacking linux-headers-4.15.0-39 (4.15.0-39.42) over (4.15.0-39.42) ...

Progress: [ 5%] [###.......................................................] 

... forcing me to kill the process and restart from beginning.

I tried forcing package removal with sudo dpkg --remove --force-remove-reinstreq linux-headers-4.15.0-39, but that didn't change anything.

One thing that might be relevant: starting sudo aptitude I get an infinite loop of the following error message:

E: Can't find a source to download version '4.15.0-39.42' of 'linux-headers-4.15.0-39:amd64'

I did not find "strange" errors in the relevant logs.

What can I do to recover dpkg from the present (very confused) state?

Update:
I'm currently trying to (force) uninstall "culprit" package (linux-headers-generic) in order to reinstall it later.