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

From: Vincenzo Frascino <vincenzo.frascino@arm.com>
To: Will Deacon <will@kernel.org>, Boyan Karatotev <boyan.karatotev@arm.com>
Cc: linux-arm-kernel@lists.infradead.org,
	linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org,
	amit.kachhap@arm.com, boian4o1@gmail.com,
	Shuah Khan <shuah@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>
Subject: Re: [PATCH v2 0/4] kselftests/arm64: add PAuth tests
Date: Mon, 14 Sep 2020 13:24:05 +0100	[thread overview]
Message-ID: <626cb564-22e1-4f2d-47c7-f38439c5fb29@arm.com> (raw)
In-Reply-To: <20200911181558.GA21319@willie-the-truck>

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