[MI400] Re: MI Entry Points

["Bruce Wilson" <bruce.wilson2@xxxxxxxxxxx>]

On earlier releases it found the EXT entry point ... currently it will execute
the first entry point regardless of type .. knowing if this is INT and that
there is no connection back to the invocation stack, and by setting return
instruction pointer with care one perhaps can violate the architecture and
open security vulnerabilities?

Leif Svalgaard wrote:

> > If the external entry point is first the code works fine.  Is there some
> > API option I missed which protects one from calling externally an
> > INTernal entry point?
> >
>
> I think so, and it must be so. The return from an INTernal entry point is
> via an instruction pointer, while the return from an EXTernal entry point
> is via the RTX instruction. Only the latter returns to a different program
> on the invocation stack. Now, there is nothing that technically prohibits
> doing what you want and it might be a wonderful thing to have, but the
> architecture forbids it. As well as security considerations.
>
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"WorldSecure Server <safeway.com>" made the following
 annotations on 03/07/03 15:47:32
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