RE: [PATCH v2 00/39] Shadowstacks for userspace

David Laight
2022-10-04T09:58:12Z

From: Kees Cook <keescook@chromium.org>
...
> >
> > If you don't want /proc/$pid/mem to be able to do stuff like that,
> > then IMO the way to go is to change when /proc/$pid/mem uses
> > FOLL_FORCE, or to limit overall write access to /proc/$pid/mem.
>
> Yeah, all reasonable. I just wish we could ditch FOLL_FORCE; it continues
> to weird me out how powerful that fd's side-effects are.

Could you remove FOLL_FORCE from /proc/$pid/mem and add a
/proc/$pid/mem_force that enable FOLL_FORCE but requires root
(or similar) access.

Although I suspect gdb may like to have write access to
code?

David

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