On 6/27/07, Theo de Raadt <[EMAIL PROTECTED]> wrote:
>
> Various developers are busy implimenting workarounds for serious bugs
> in Intel's Core 2 cpu.
>
> These processors are buggy as hell, and some of these bugs don't just
> cause development/debugging problems, but will *ASSUREDLY* be
> exploitable from userland code.
>
> As is typical, BIOS vendors will be very late providing workarounds /
> fixes for these processors bugs.  Some bugs are unfixable and cannot
> be worked around.  Intel only provides detailed fixes to BIOS vendors
> and large operating system groups.  Open Source operating systems are
> largely left in the cold.
>
> Full (current) errata from Intel:
>
> http://download.intel.com/design/processor/specupdt/31327914.pdf
>
> - We bet there are many more errata not yet announced -- every month
>    this file gets larger.
> - Intel understates the impact of these erraata very significantly.
>    Almost all operating systems will run into these bugs.
> - Basically the MMU simply does not operate as specified/implimented
>    in previous generations of x86 hardware.  It is not just buggy, but
>    Intel has gone further and defined "new ways to handle page tables"
>    (see page 58).
> - Some of these bugs are along the lines of "buffer overflow"; where
>    a write-protect or non-execute bit for a page table entry is ignored.
>    Others are floating point instruction non-coherencies, or memory
>    corruptions -- outside of the range of permitted writing for the
>    process -- running common instruction sequences.
> - All of this is just unbelievable to many of us.
>
> An easier summary document for some people to read:
>
>
> http://www.geek.com/images/geeknews/2006Jan/core_duo_errata__2006_01_21__full.gif
>
> Note that some errata like AI65, AI79, AI43, AI39, AI90, AI99 scare
> the hell out of us.  Some of these are things that cannot be fixed in
> running code, and some are things that every operating system will do
> until about mid-2008, because that is how the MMU has always been
> managed on all generations of Intel/AMD/whoeverelse hardware.  Now
> Intel is telling people to manage the MMU's TLB flushes in a new and
> different way.  Yet even if we do so, some of the errata listed are
> unaffected by doing so.
>
> As I said before, hiding in this list are 20-30 bugs that cannot be
> worked around by operating systems, and will be potentially
> exploitable.  I would bet a lot of money that at least 2-3 of them
> are.
>
> For instance, AI90 is exploitable on some operating systems (but not
> OpenBSD running default binaries).
>
> At this time, I cannot recommend purchase of any machines based on the
> Intel Core 2 until these issues are dealt with (which I suspect will
> take more than a year).  Intel must be come more transparent.
>
> (While here, I would like to say that AMD is becoming less helpful day
> by day towards open source operating systems too, perhaps because
> their serious errata lists are growing rapidly too).


So who currently (if anybody) is cooperating nicely?  This is a sad state of
affairs.

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