ps -ef displays kerneloops - is that harmful?

No it's not harmful...

apt show kerneloops

kerneloops is a daemon that collects kernel crash information and then submits the extracted signature to the oops.kernel.org website for statistical analysis and presentation to the Linux kernel developers.

If you have aptitude installed you can run:

aptitude why kerneloops

to see why it has been installed (if it wasn't installed by default).

I guess it's installed by default, because at least you should have ubuntu-desktop installed on a default installation (Main flavor) and it's depend on kerneloops:

$ apt-cache rdepends kerneloops | grep desk
  lubuntu-qt-desktop
  lubuntu-gtk-desktop
  lubuntu-desktop
  xubuntu-desktop
  vanilla-gnome-desktop
  ubuntustudio-desktop-core
  ubuntustudio-desktop
  ubuntukylin-desktop
  ubuntu-mate-desktop
  ubuntu-budgie-desktop
  lubuntu-qt-desktop
  lubuntu-gtk-desktop
  lubuntu-desktop
  kubuntu-desktop
  ubuntu-desktop