Group of device files changes after running VirtuaBox with "raw partitions image"

[toralf]

I'm using VirtualBox to run a "real" Windows 10 installation, using an image created according to the instructions in section 9.9.1.2 under https://www.virtualbox.org/manual/ch09.html#rawdisk. The actual partition numbers specified were 1,2,3 in my case.

This works fairly well, but there is one slight issue: The group ownership of the /dev files corresponding to the above mentioned partitions changes after I complete the VirtualBox session. The following sequence of shell commands and output should illustrate what happens:

[toralf@osl-97214 ~]$ ls -tlra /dev/sda[123]
brw-rw---- 1 root disk 8, 1 Mar  7 14:54 /dev/sda1
brw-rw---- 1 root disk 8, 3 Mar  7 14:54 /dev/sda3
brw-rw---- 1 root disk 8, 2 Mar  7 14:54 /dev/sda2
[toralf@osl-97214 ~]$ VirtualBox --startvm Win10partition
[toralf@osl-97214 ~]$ ls -tlra /dev/sda[123]
brw-rw---- 1 root root 8, 1 Mar  7 15:05 /dev/sda1
brw-rw---- 1 root root 8, 3 Mar  7 15:05 /dev/sda3
brw-rw---- 1 root root 8, 2 Mar  7 15:05 /dev/sda2

Note that the first output represents the way everything looks after a reboot.

This is a bit annoying as it means I can't give a regular users access to the Windows installation via addition to group "disk". Or rather, I can, but there can only be one VirtualBox session after each boot, unless someone intervenes. I guess I can add users to "root", to, but I'm somehow less comfortable doing that.