Re: [PATCH v20 06/25] x86/cet: Add control-protection fault handler

From: Kees Cook
Date: Wed Feb 10 2021 - 14:37:57 EST


On Wed, Feb 10, 2021 at 09:56:44AM -0800, Yu-cheng Yu wrote:
> A control-protection fault is triggered when a control-flow transfer
> attempt violates Shadow Stack or Indirect Branch Tracking constraints.
> For example, the return address for a RET instruction differs from the copy
> on the shadow stack; or an indirect JMP instruction, without the NOTRACK
> prefix, arrives at a non-ENDBR opcode.
>
> The control-protection fault handler works in a similar way as the general
> protection fault handler. It provides the si_code SEGV_CPERR to the signal
> handler.
>
> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

--
Kees Cook