Re: [PATCH] Prefer kASLR over Hibernation

[Geert Uytterhoeven]

On Mon, Apr 11, 2016 at 8:03 PM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> On Mon, Apr 11, 2016 at 1:00 AM, James Morse <james.morse@xxxxxxx> wrote:
>> On 06/04/16 20:44, Kees Cook wrote:
>>> When building with both CONFIG_HIBERNATION and CONFIG_RANDOMIZE_BASE,
>>> one or the other must be chosen at boot-time. Until now, hibernation
>>> was selected when no choice was made on the command line.
>>>
>>> To make the security benefits of kASLR more widely available to end
>>> users (since the use of hibernation is becoming more rare and kASLR,
>>> already available on x86, will be available on arm64 and MIPS soon),
>>> this changes the default to preferring kASLR over hibernation. Users
>>> wanting hibernation can turn off kASLR by adding "nokaslr" to the kernel
>>> command line.
>>
>> While hibernate isn't yet merged for arm64, it does work with kASLR in v4.6-rc*,
>> it would be a shame to have to choose at boot time, (but that's my problem to
>> fix if/when its merged).
>
> Ah, interesting, so they work together on arm64? (i.e. you've actually
> tested a boot loader that provides the seed for kASLR to operate?)

Probably the PS3 people can provide us with a good tool to generate a
seed that makes hibernation work all the time ;-)

https://xkcd.com/221/

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds