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Re: BPF Extended: addressing BPF's shortcomings


From: "Paul \"LeoNerd\" Evans" <leonerd () leonerd org uk>
Date: Thu, 11 Jun 2015 10:37:54 +0100

On Wed, 10 Jun 2015 19:25:58 -0700
Guy Harris <guy () alum mit edu> wrote:

...with some way of preventing infinite loops in the kernel, even if
it's as crude as "there's a pointer into the packet and  if you do a
backwards jump without moving that pointer forwards and checking to
make sure you haven't gone beyond the end of the packet, the filter
program immediately fails".  (Yes, that means it's no longer
Turing-complete, as there's no longer a halting problem. :-))

That's exactly what my LOOP instruction suggestion does.

-- 
Paul "LeoNerd" Evans

leonerd () leonerd org uk
http://www.leonerd.org.uk/  |  https://metacpan.org/author/PEVANS
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