Floppy Boot, Filesystem, and Diags (was Re: 3.5" floppy disk revisited)

Alex Crain alex at wolf.umbc.edu
Sat May 6 14:18:22 AEST 1989


In article <678 at mitisft.Convergent.COM> dold at mitisft.Convergent.COM (Clarence Dold) writes:

>I don't think I would want /bin/mv as setuid root on my system.
>Kind of eliminates permissions on a directory.

	Actually, life gets a tad frustrating if /bin/mv is *not* suid, because
only root can modify a directory entry, regardless of the owner. This is in
order to prevent lowly users from doing things like

	ln /u/nerd /u/nerd/dufus

which would be something akin to *very bad*.

	Fortunately, /bin/mv (and ln & cp) is aware of its awsome 
responsibility as a suid program, and takes all the appropriate precations
to make sure that lowly users don't evade the permissions system.

	A friend of mine once swiped a set of zenix binaries for use on
his PC/AT. The command he used was akin to "tar c /", and he neglected
to get a list of suid programs. It took him two weeks to figure out why
he couldn't do anything unless he was root :-)

					:alex
Alex Crain
Systems Programmer			alex at umbc3.umbc.edu
Univ Md Baltimore County		umbc3.umbc.edu!nerwin!alex



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