lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 7 Feb 2024 10:04:56 +0000
From: Mark Brown <broonie@...nel.org>
To: Dave Martin <Dave.Martin@....com>
Cc: linux-arm-kernel@...ts.infradead.org, Will Deacon <will@...nel.org>,
	Catalin Marinas <catalin.marinas@....com>,
	Oleg Nesterov <oleg@...hat.com>, Al Viro <viro@...iv.linux.org.uk>,
	linux-kernel@...r.kernel.org, Doug Anderson <dianders@...omium.org>
Subject: Re: [RFC PATCH] arm64/sve,sme: Refine scalable regset sizes at boot

On Mon, Feb 05, 2024 at 05:27:20PM +0000, Dave Martin wrote:

> index a5dc6f764195..5c2f91f84c31 100644
> --- a/arch/arm64/kernel/fpsimd.c
> +++ b/arch/arm64/kernel/fpsimd.c
> @@ -1189,6 +1189,7 @@ void __init sve_setup(void)
>  		pr_warn("%s: unvirtualisable vector lengths present\n",
>  			info->name);
>  
> +	arch_ptrace_sve_init(sve_vq_from_vl(info->max_vl));
>  	sve_efi_setup();
>  }

This will only get run if the system actually supports SVE since the
first thing that sve_setup() does is to exit if the system does not
support SVE.  That means that the size limiting will only be done on
systems that have SVE, but since we unconditionally register all our
regsets if the system doesn't have SVE it will end up with a maximally
sized SVE regset registered which doesn't seem ideal.  As I mentioned in
the other thread we should probably just not be registering unsupported
regsets with the core, that would avoid the issue without a change to
this patch.

A similar issue applies for SME.

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ