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Re: Improvements in amd64



On Fri, May 13, 2016 at 05:42:55PM +0200, Maxime Villard wrote:
> Initially, two chunks were mapped contiguously in both amd64 and i386:
>  - text+rodata with RX permissions

Thanks for the detailed explanation.

What I still don't get is why you seem to think that an additional X
in the mapping for .rodata is so terrible - as long as there is no W
I don't see the additional attack vector you are trying to elliminate.

If the separate mapping just falls out from other cleanup/optimizations,
then of course it is fine and more correct. But out of gut feeling I 
wouldn't have thought it to be important in any way (and other architectures
treat is as RX too, so should they take a hint from this?)

Martin


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