Re: [PATCH 0/7] CFI for ARM32 using LLVM

Kees Cook
2024-02-27T18:01:41Z

On Tue, Feb 27, 2024 at 02:48:13PM +0100, Linus Walleij wrote:
> On Tue, Feb 27, 2024 at 2:06 AM Kees Cook <keescook@chromium.org> wrote:
>
> > On Sun, Feb 25, 2024 at 09:08:09PM +0100, Linus Walleij wrote:
> > > This is a first patch set to support CLANG CFI (Control Flow
> > > Integrity) on ARM32.
> >
> > Yay!
> >
> > Is CONFIG_CFI_PERMISSIVE=y expected to work with this series?
>
> I enable that and what happens when I trigger a crash is that the
> process shell is killed and I return to login prompt (busybox).
> I guess that is expected behaviour for permissive?

No, permissive should just issue a WARN and continue running. I think
you need wire up report_cfi_failure(), see cfi_handler() in arm64.

But non-permissive is working great! :)

--
Kees Cook