Re: [RFC/RFT] CFI: Add support for gcc CFI in aarch64

Dan Li
2022-12-19T13:32:17Z

Hi Peter,

On 12/19, Peter Zijlstra wrote:
> On Sun, Dec 18, 2022 at 10:17:58PM -0800, Dan Li wrote:
>
> > 1. When a typeid mismatch is detected, the cfi_check_failed function
> > will be called instead of the brk instruction. This function needs
> > to be implemented by the compiler user.
> > If there are user mode programs or other systems that want to use
> > this feature, it may be more convenient to use a callback (so this
> > compilation option is set to -fsanitize=cfi instead of kcfi).
>
> This is not going to be acceptible for x86_64.

I'm not familiar enough with the x86_64 platform, could you please
tell me why this is not acceptable? Is there a similar situation
on the arm64 platform?

> > 5. The current implementation of gcc only supports the aarch64 platform.
>
> What, if any, are the plans for x86_64 support?

I'd like to implement something similar on x86_64 later, but
currently I'm doing this in my spare time, so it might take a
little longer. :(

Thanks,
Dan