From owner-freebsd-security  Wed Jun 24 08:01:36 1998
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Date: Wed, 24 Jun 1998 18:02:19 +0400 (MSD)
From: Stas Kisel <stas@ssu.ccssu.crimea.ua>
Message-Id: <199806241402.SAA11520@ssu.ccssu.crimea.ua>
To: ncb05@uow.edu.au, njs3@doc.ic.ac.uk, security@FreeBSD.ORG
Subject: Re: non-executable stack?
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> From: njs3@doc.ic.ac.uk (Niall Smart)
> Date: Wed, 24 Jun 1998 15:09:30 +0100
> It would be nice to have a filesystem non-executable-stack flag so that
> it could be enabled/disabled on a per file basis.  Another option would
> be to only turn it on for set[ug]id executables.  There are a number

This option seems not so useful - many buffer overruns are(and will be)
written for exploiting via network non-suid daemons, run as root or ever
as nobody. E.g. overruns in CGI-scripts.

> of other "features" like this that would be useful, for example the
> ability to specify that only printable ascii characters can appear in
> the arguments or environment of a process before it can exec another.
> I haven't checked if its possible to write shellcode using just plain
> ascii characters,  if you can then this is obviously worthless, but I'd
> be surprised if it's possible.

\bye
Stas


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