Re: [PATCH 0/5] riscv: SCS support

Kees Cook
2023-08-14T21:09:30Z

On Mon, Aug 14, 2023 at 01:18:30PM -0700, Sami Tolvanen wrote:
> On Mon, Aug 14, 2023 at 11:57 AM Sami Tolvanen <samitolvanen@google.com> wrote:
> > Looks like __builtin_frame_address behaves differently on RISC-V.
> > After staring at the disassembly a bit, using
> > __builtin_frame_address(0) - 1 instead of + 1 seems to yield correct
> > results.
>
> Elliott was kind enough to point out to me off-list that this behavior
> has been documented here:
>
> https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-cc.adoc#frame-pointer-convention
>
> I'll include a patch to fix the test on RISC-V in the next version.

Perfect! Thanks for figuring out the offset. :)

--
Kees Cook