Re: [RFC PATCH] UML: add support for KASAN under x86_64

[Patricia Alfonso]

On Thu, Jan 16, 2020 at 12:53 AM Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote:
>
> > +void kasan_init(void)
> > +{
> > +       kasan_map_memory((void *)KASAN_SHADOW_START, KASAN_SHADOW_SIZE);
> > +
> > +       // unpoison the kernel text which is form uml_physmem -> uml_reserved
> > +       kasan_unpoison_shadow((void *)uml_physmem, physmem_size);
> > +
> > +       // unpoison the vmalloc region, which is start_vm -> end_vm
> > +       kasan_unpoison_shadow((void *)start_vm, (end_vm - start_vm + 1));
> > +
> > +       init_task.kasan_depth = 0;
> > +       pr_info("KernelAddressSanitizer initialized\n");
> > +}
>
> Was this tested with stack instrumentation? Stack instrumentation
> changes what shadow is being read/written and when. We don't need to
> get it working right now, but if it does not work it would be nice to
> restrict the setting and leave some comment traces for future
> generations.
If you are referring to KASAN_STACK_ENABLE, I just tested it and it
seems to work fine.

-- 
Patricia Alfonso