From: stephen@glas.rtsg.mot.com (Stephen Shortland) Subject: Re: Allowing others to mount ? Date: Wed, 21 Apr 1993 09:24:54 GMT
sct@dcs.ed.ac.uk (Stephen Tweedie) writes:
>> It is a huge security hole (or shall I say canyon) to allow anyone other
>> than root to mount a drive. I could just see some wiseguy mounting his
>> own linux boot disk and zapping your drive.
>There is no problem as long as you have a suid-root mount program
>which forces all mounts by normal users to have the no-suid bits set,
>and which only allows removable media to be mounted.
You also need to severly restrict the mount points that the program can
use. Otherwise someone could, for example, mount a disk which contains
a trojan version of some common program (ls!) over /usr/bin, and hey
presto, the next time that root types ls the sustem is compromised!
[/usr/bin is probably a bad example, as there will probably always be
some program in there in use, which should cause the mount to fail.
However it wouldn't take much imagination to come up with some other
place that a directory could be mounted to compromise security]
Stephen...
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