[Info-vax] How dangerous is it to be able to get into DCL supervisor mode ?

[Simon Clubley]

On 2017-07-03, VAXman-  @SendSpamHere.ORG <VAXman- at SendSpamHere.ORG> wrote:
>
> When in exec mode, one can invoke $CMKRNL and execute code in kernel
> mode without possessing the privies needed for $CMKRNL because there
> is a check for the previous mode being exec.  There's nothing similar
> for $CMEXEC from supervisor mode.  It sure would have removed a few
> hurdles for me when writing my DCL Debugger had that been the case.
>

Thanks Brian.

There's still the bit about being able to set the privilege bits
in supervisor mode however.

However, if supervisor mode lets you do that, then that would seem to
defeat the whole point of actually _having_ a supervisor mode. :-)

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
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