Re: [PATCH v4 1/2] bpf: add __weak hook for allocating executable memory

[Kees Cook]

On Mon, Nov 26, 2018 at 9:02 AM Edgecombe, Rick P
<rick.p.edgecombe@xxxxxxxxx> wrote:
>
> On Fri, 2018-11-23 at 23:18 +0100, Ard Biesheuvel wrote:
> > By default, BPF uses module_alloc() to allocate executable memory,
> > but this is not necessary on all arches and potentially undesirable
> > on some of them.
> >
> > So break out the module_alloc() and module_memfree() calls into __weak
> > functions to allow them to be overridden in arch code.
> >
> > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
> > ---
>
> It looks like some of the architectures call module_alloc directly in their
> bpf_jit_compile implementations as well.

Ew, good catch. :P

-- 
Kees Cook