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Message-ID: <3C62025D.4070102@edu.stadia.fi>
From: Antti Koskipaa <antti DOT koskipaa AT edu DOT stadia DOT fi>
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Newsgroups: comp.os.msdos.djgpp
Subject: Re: FSDB and descriptor tables
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Date: Wed, 06 Feb 2002 20:28:13 -0800
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Eli Zaretskii wrote:
> The sources of FSDB are freely available for studying (get
> djlsr203.zip, and look there in src/debug/fsdb/ directory).

I see. I was referring with my own DS, instead of _dos_ds.

> No, you are wrong: SGDT and SLDT are not privileged instructions, as
> they only read the tables, but not modify them.  And there's nothing
> special about how those tables are mapped.

So... The OS allows direct reading of the descriptors. Gotta test
if they are writeable too... That would be a major security hole.

--
- Antti