* Kees Cook <keesc...@chromium.org> wrote:
> On Thu, Apr 28, 2016 at 2:04 AM, Ingo Molnar <mi...@kernel.org> wrote:
> >
> > * Kees Cook <keesc...@chromium.org> wrote:
> > > +#define memmove memmove
> >
> > Btw., what's the purpose of this define? If it's already defined then we
> > should
> > get a build warning. If it's not, we won't.
>
> It's for the decompressor that checks for memmove existing already via
> "ifdef memmove". If this isn't done here, we will end up with two
> memmove implementations.
So:
triton:~/tip> git grep memmove | grep -i ifdef
triton:~/tip>
what am I missing?
> >> +void *memcpy(void *dest, const void *src, size_t n)
> >
> > btw., if there's any doubt about other overlapping uses, we could add this
> > to
> > memcpy():
> >
> > WARN_ON_ONCE(dest > src && dest-src < n);
> >
> > or so? Does printk() work so early on?
>
> It does not, but we could use either "error" or the new "warn". Should
> we abort a boot in this case, or just warn about it? (Our
> implementations of memcpy, fwiw, currently seem to support overlap, so
> I would suggest warn.)
Yeah, I'd definitely not try to crash the bootup for the user, but try to
continue.
Thanks,
Ingo
