What reason should /dev/kmem not be world-readable?

[Crispin Goswell]

In article <8532 at rpp386.Dallas.TX.US> jfh at rpp386.Dallas.TX.US (John F. Haugh II) writes:
>
>This can be very dangerous.  Letting one of those run on a terminal
>root or some other privileged user is likely to use could have nasty
>results.
>
>/dev/kmem should never be readable by regular users.  ps and other
>kernel pokers should run S(U|G)ID the owner of the device.

There is another reason: some machines have memory mapped devices, which
can be disturbed even by reading their device registers.
Thus system integrity can be affected, as well as security.
-- 

Name:   Crispin Goswell		 	  |-------|__   Informatics Department
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