Re: [PATCH 0/2] make kASLR vs hibernation boot-time selectable

From: H. Peter Anvin
Date: Fri Jun 13 2014 - 13:38:03 EST


On 06/13/2014 10:32 AM, Kees Cook wrote:
>>
>> x86-64 can resume from different kernel that did the suspend. kASLR
>> should not be too different from that. (You just include kernel text
>> in the hibernation image. It is small enough to do that.)
>
> Oooh, that's very exciting! How does that work (what happens to the
> kernel that booted first, etc)? I assume physical memory layout can't
> change between hibernation and resume? Or, where should I be reading
> code that does this?
>

"Give me a lever and a place to stand, and I shall move the world."
Reshuffling memory in an arbitrary or near-arbitrary way really isn't
all that hard. The exact data structures you need depends on if you
have any kind of page alignment you can rely on (makes it easier) and
how much spare memory you have (in case of hibernation, there is usually
tons of unused memory as it doesn't make sense to hibernate clean pages.)

-hpa


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/