linux-kernel - Re: [PATCH] ARM: small correction to early

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:   Tue, 27 Jun 2017 10:46:18 +0000
From:   Ard Biesheuvel <ard.biesheuvel@...aro.org>
To:     Doug Berger <opendmb@...il.com>
Cc:     Russell King <linux@...linux.org.uk>,
        Laura Abbott <labbott@...hat.com>,
        Nicolas Pitre <nicolas.pitre@...aro.org>,
        Jon Medhurst <tixy@...aro.org>,
        Florian Fainelli <f.fainelli@...il.com>,
        Kees Cook <keescook@...omium.org>,
        Marc Zyngier <marc.zyngier@....com>,
        "moderated list:ARM PORT" <linux-arm-kernel@...ts.infradead.org>,
        open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] ARM: small correction to early_ioremap support

On 27 June 2017 at 00:57, Doug Berger <opendmb@...il.com> wrote:
> The fixmap pages need to be on the same pmd page for the current
> implementation of arm early_fixmap.  A build time bug check is
> used to ensure that.  However, the worst case fixmap range is
> better represented by __end_of_fixed_addresses than by the value
> __end_of_early_ioremap_region.
>
> Fixes: 2937367b8a4b ("ARM: add support for generic early_ioremap/early_memremap")
> Signed-off-by: Doug Berger <opendmb@...il.com>
> ---
>  arch/arm/mm/mmu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
> index 31af3cb59a60..74c0ed5c3b08 100644
> --- a/arch/arm/mm/mmu.c
> +++ b/arch/arm/mm/mmu.c
> @@ -392,7 +392,7 @@ void __init early_fixmap_init(void)
>          * The early fixmap range spans multiple pmds, for which
>          * we are not prepared:
>          */
> -       BUILD_BUG_ON((__fix_to_virt(__end_of_early_ioremap_region) >> PMD_SHIFT)
> +       BUILD_BUG_ON((__fix_to_virt(__end_of_fixed_addresses) >> PMD_SHIFT)
>                      != FIXADDR_TOP >> PMD_SHIFT);
>
>         pmd = fixmap_pmd(FIXADDR_TOP);

Acked-by: Ard Biesheuvel <ard.biesheuvel@...aro.org>