To enable changing file owners & permissions, you need to edit /etc/wsl.conf and insert the below config options:
[automount]
options = "metadata"
Do this inside the WSL shell, potentially needing sudo to edit/create the file.
This may require restarting WSL (such as with wsl --shutdown which is a Windows command, not one within WSL) or the host machine to take effect. This has been possible since 2018:
You can now set the owner and group of files using chmod/chown and modify read/write/execute permissions in WSL. You can also create special files like fifos, unix sockets, and device files. We’re introducing new mounting options with DrvFs for projecting permissions onto files alongside providing new Linux metadata on files and folders.
Both Amades and Chaos answers are correct.
But it only works for local drives not for mapped network drives. Z: is one of my network drives. Same operation on /mnt/c/Users/xxx/ works fine.
$sudo mount -t drvfs Z: /mnt/z -o metadata
$touch test
$chmod +w test
chmod: changing permissions of 'test': Operation not permitted