> why do "/sbin/mount_ados" and "/sbin/mount_msdos" in the NetBSD 1.0
> distribution come with setuid ? This way EVERY user can mount devices

No, they can mount things only if a certain set of conditions are met,
namely:
	(1) they have appropriate permissions on the device's /dev
		entries
	(2) they have appropriate permissions on the to-be-mounted-on
		directory.

> but he can't even unmount them.

Indeed, they _can_ unmount them; user-created mounts are unmountable
by the user who created them, and by root.

> I spended a half our to protect my
> AmigaDOS partition and had to decover that with the original configuration
> everybody would have been able to access my data any way.

did you actually try to mount your amigados partition as a 'random'
user?  if it worked, what do the permissions on its device node look like?

don't assume that just because something is named "mount_*" and is
set-id that anybody can use it to mount anything...



cgd