Messages in this thread | | | From | Kees Cook <> | Date | Thu, 15 Feb 2018 17:03:25 -0800 | Subject | Re: [PATCH -mm 1/3] proc: randomize "struct pde_opener" |
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On Thu, Feb 15, 2018 at 4:13 PM, Al Viro <viro@zeniv.linux.org.uk> wrote: > Guess what happens to cache footprint of dcache lookups if the bunch in the > beginning gets spread over the entire thing? Right... And that's besides the > outright miscompiles.
Mentioned in private communication, but just for posterity: GCC_PLUGIN_RANDSTRUCT_PERFORMANCE exists specifically to address those kinds of performance concerns.
As to removing the markings: please don't. Instead, you'd mentioned wanting to add a TAINT flag for this, and I think that sounds entirely reasonable. We have TAINT flags for considerably less insane things. :) I can send that patch.
-Kees
-- Kees Cook Pixel Security
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