oci-umount.conf man page
oci-umount.conf — oci-umount configuration file
The oci-umount.conf file contains a list of paths on host which will be unmounted inside container. (If they are mounted inside container).
If there is a "/*" at the end, that means only mounts underneath that mounts (submounts) will be unmounted but top level mount will remain in place.
/var/lib/docker/overlay2 /var/lib/docker/overlay /var/lib/docker/devicemapper /var/lib/docker/containers/* /var/lib/docker-latest/overlay2 /var/lib/docker-latest/overlay /var/lib/docker-latest/devicemapper /var/lib/docker-latest/containers/* /var/lib/containers/storage/* /run/containers/storage/* /var/lib/origin/*