[RFC PATCH V1 4/8] kasan: Don't use kasan shadow pointer in generic functions

[Andrey Ryabinin]

On 08/17/2015 09:36 AM, Aneesh Kumar K.V wrote:
> We can't use generic functions like print_hex_dump to access kasan
> shadow region. This require us to setup another kasan shadow region
> for the address passed (kasan shadow address). Most architecture won't
> be able to do that. Hence remove dumping kasan shadow region dump. If
> we really want to do this we will have to have a kasan internal implemen
> tation of print_hex_dump for which we will disable address sanitizer
> operation.
>

I didn't understand that.
Yes, you don't have shadow for shadow. But, for shadow addresses you
return return (void *)kasan_zero_page in kasan_mem_to_shadow(), so we
should be fine to access shadow in generic code.

And with kasan_tracks_vaddr(), this should work too.