Re: [PATCH v4 10/17] arm64: disable kretprobes with SCS

From: Sami Tolvanen
Date: Mon Nov 04 2019 - 18:42:24 EST


On Mon, Nov 4, 2019 at 9:05 AM Mark Rutland <mark.rutland@xxxxxxx> wrote:
> I'm a bit confused as to why that's the case -- could you please
> elaborate on how this is incompatible?
>
> IIUC kretrobes works by patching the function entry point with a BRK, so
> that it can modify the LR _before_ it is saved to the stack. I don't see
> how SCS affects that.

You're correct. While this may not be optimal for reducing attack
surface, I just tested this to confirm that there's no functional
conflict. I'll drop this and related patches from v5.

Sami