Re: [PATCH v7 22/39] arm64/gcs: Implement shadow stack prctl() interface

From: Thiago Jung Bauermann
Date: Wed Dec 06 2023 - 16:27:39 EST



Mark Brown <broonie@xxxxxxxxxx> writes:

> Implement the architecture neutral prtctl() interface for setting the
> shadow stack status, this supports setting and reading the current GCS
> configuration for the current thread.
>
> Userspace can enable basic GCS functionality and additionally also
> support for GCS pushes and arbatrary GCS stores. It is expected that

s/arbatrary/arbitrary/

> this prctl() will be called very early in application startup, for
> example by the dynamic linker, and not subsequently adjusted during
> normal operation. Users should carefully note that after enabling GCS
> for a thread GCS will become active with no call stack so it is not
> normally possible to return from the function that invoked the prctl().

--
Thiago