[PATCH 1/2] scs: switch to vmapped shadow stacks

[Kees Cook]

On Thu, Oct 22, 2020 at 01:23:54PM -0700, Sami Tolvanen wrote:
> The kernel currently uses kmem_cache to allocate shadow call stacks,
> which means an overflow may not be immediately detected and can
> potentially result in another task's shadow stack to be overwritten.
> 
> This change switches SCS to use virtually mapped shadow stacks,
> which increases shadow stack size to a full page and provides more
> robust overflow detection similarly to VMAP_STACK.
> 
> Signed-off-by: Sami Tolvanen <samitolvanen at google.com>

Thanks! I much prefer this to kmem. :)

Reviewed-by: Kees Cook <keescook at chromium.org>

-- 
Kees Cook