linux-kernel - Re: [PATCH] x86/asm: Pin sensitive CR4 bits

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]

Message-ID: <20190220081451.GA2254@light.dominikbrodowski.net>
Date:   Wed, 20 Feb 2019 09:14:51 +0100
From:   Dominik Brodowski <linux@...inikbrodowski.net>
To:     Kees Cook <keescook@...omium.org>
Cc:     Thomas Gleixner <tglx@...utronix.de>, linux-kernel@...r.kernel.org,
        kernel-hardening@...ts.openwall.com, x86@...nel.org
Subject: Re: [PATCH] x86/asm: Pin sensitive CR4 bits

On Tue, Feb 19, 2019 at 04:54:49PM -0800, Kees Cook wrote:
> diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
> index cb28e98a0659..7e0ea4470f8e 100644
> --- a/arch/x86/kernel/cpu/common.c
> +++ b/arch/x86/kernel/cpu/common.c
> @@ -312,10 +312,16 @@ static __init int setup_disable_smep(char *arg)
>  }
>  __setup("nosmep", setup_disable_smep);
>  
> +volatile unsigned long cr4_pin __ro_after_init;
> +EXPORT_SYMBOL_GPL(cr4_pin);

Where is this export needed?

Thanks,
	Dominik