From: "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
Subject: Re: General flags to turn things off (getrandom, pid lookup, etc)
Date: Fri, 25 Jul 2014 16:43:20 -0700
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To: Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>,
	"Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>,
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	Paolo Bonzini <pbonzini-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
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	Greg Kroah-Hartman <gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>,
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On 07/25/2014 11:30 AM, Andy Lutomirski wrote:
>     - 32-bit GDT code segments [huge attack surface]
>     - 64-bit GDT code segments [probably pointless]

I presume you mean s/GDT/LDT/.

We already don't allow 64-bit LDT code segments.  Also, it is unclear to
me how 32-bit LDT segments have a huge attack surface, given that there
will realistically always be a 32-bit *GDT* segment present.

	-hpa