Re: [RFC][PATCH] Randomize kernel base address on boot

H. Peter Anvin
2011-05-31T19:08:46Z

On 05/31/2011 12:03 PM, Dan Rosenberg wrote:
>
> Just for the record, I've put this patch on hold until there's some more
> consensus about whether boot-time randomization of the physical kernel
> address is the best approach. There are some other potential issues
> that haven't been brought up yet publicly, such as the possibility of
> local attackers performing cache timing attacks to find the kernel image
> location at runtime, which may make traditional ASLR somewhat pointless
> regardless (except in the case of remote attackers, I suppose). Perhaps
> HPA's suggestion of further modularizing the kernel would have some
> advantages in this regard.
>

I'm probably going to implement the whole-image randomization as an
option in the Syslinux bootloader; it is a *lot* easier to do this
correctly in the bootloader.

-hpa