Re: [PATCH v2 0/4] kselftests/arm64: add PAuth tests

From: Vincenzo Frascino
Date: Mon Sep 14 2020 - 08:31:46 EST


Hi Will,

On 9/11/20 7:15 PM, Will Deacon wrote:
> On Mon, Aug 31, 2020 at 12:04:46PM +0100, Boyan Karatotev wrote:
>> Pointer Authentication (PAuth) is a security feature introduced in ARMv8.3.
>> It introduces instructions to sign addresses and later check for potential
>> corruption using a second modifier value and one of a set of keys. The
>> signature, in the form of the Pointer Authentication Code (PAC), is stored
>> in some of the top unused bits of the virtual address (e.g. [54: 49] if
>> TBID0 is enabled and TnSZ is set to use a 48 bit VA space). A set of
>> controls are present to enable/disable groups of instructions (which use
>> certain keys) for compatibility with libraries that do not utilize the
>> feature. PAuth is used to verify the integrity of return addresses on the
>> stack with less memory than the stack canary.
>
> Any chance of a v3 addressing the couple of small comments from Dave on
> the third patch, please? Then I can pick up the whole lot for 5.10.
>

Boyan is on it. Thank you.

> Cheers,
>
> Will
>

--
Regards,
Vincenzo