[TUHS] directories going away.

The JHU version of the V6 kernel and the mount program were modified (or should I say buggered) so that unprivileged users could mount user packs. There were certain restrictions added as well: no setuid on mounted volumes etc. The problem came up that people would mount them using relative paths and the mtab wouldn't really show who was using the disk as a result. I suggested we just further bugger it by making the program chdir to '/dev' first. That way you wouldn't have to put /dev/ on the drive device and you'd have to give an absolute path for the mount point (or at least one relative to /dev). I pointed out to my coworker that there was nothing in /dev/ to mount on. He started trying it. Well the kernel issued errors for trying to use a special file as a mount point. He then tried "." Due to a combination of bugs that worked! The only problem, is how do you unmount it? The /dev nodes had been replaced by the root of directory of my user pack. Oh well, go halt and reboot. There were supposed to be protections against this. Mind you I did not have root access at this point (just a lowly student operator), so we decided to see where else we could mount. Sure enough cd /etc/ and mount on "." there. We made up our own password file. It had one account with uid 0 and the name "Game Player" in the gcos field. About this one of the system managers calls and tells us to halt the machine as it'd had been hacked. I told him we were responsible and we'd undo what we did. I think by this time Mike Muuss came out and gave me the "mount" source and told me to fix it.