linux-kernel - Re: [PATCH v2 4/6] riscv: Fix EFI stub usage of KASAN instrumented strcmp function

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: <CAMj1kXEk0Vpf6-_iVwyg36MWtQa5HXGdExDzaFU5-12179shmw@mail.gmail.com>
Date:   Mon, 23 Jan 2023 11:19:15 +0100
From:   Ard Biesheuvel <ardb@...nel.org>
To:     Alexandre Ghiti <alexghiti@...osinc.com>
Cc:     Paul Walmsley <paul.walmsley@...ive.com>,
        Palmer Dabbelt <palmer@...belt.com>,
        Albert Ou <aou@...s.berkeley.edu>,
        Andrey Ryabinin <ryabinin.a.a@...il.com>,
        Alexander Potapenko <glider@...gle.com>,
        Andrey Konovalov <andreyknvl@...il.com>,
        Dmitry Vyukov <dvyukov@...gle.com>,
        Vincenzo Frascino <vincenzo.frascino@....com>,
        linux-riscv@...ts.infradead.org, linux-kernel@...r.kernel.org,
        kasan-dev@...glegroups.com, linux-efi@...r.kernel.org,
        Alexandre Ghiti <alexghiti@...xghiti.eu.rivosinc.com>
Subject: Re: [PATCH v2 4/6] riscv: Fix EFI stub usage of KASAN instrumented
 strcmp function

On Mon, 23 Jan 2023 at 11:14, Alexandre Ghiti <alexghiti@...osinc.com> wrote:
>
> From: Alexandre Ghiti <alexghiti@...xghiti.eu.rivosinc.com>
>
> The EFI stub must not use any KASAN instrumented code as the kernel
> proper did not initialize the thread pointer and the mapping for the
> KASAN shadow region.
>
> Avoid using the generic strcmp function, instead use the one in
> drivers/firmware/efi/libstub/string.c.
>
> Signed-off-by: Alexandre Ghiti <alexghiti@...osinc.com>

Acked-by: Ard Biesheuvel <ardb@...nel.org>

> ---
>  arch/riscv/kernel/image-vars.h | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/arch/riscv/kernel/image-vars.h b/arch/riscv/kernel/image-vars.h
> index 7e2962ef73f9..15616155008c 100644
> --- a/arch/riscv/kernel/image-vars.h
> +++ b/arch/riscv/kernel/image-vars.h
> @@ -23,8 +23,6 @@
>   * linked at. The routines below are all implemented in assembler in a
>   * position independent manner
>   */
> -__efistub_strcmp               = strcmp;
> -
>  __efistub__start               = _start;
>  __efistub__start_kernel                = _start_kernel;
>  __efistub__end                 = _end;
> --
> 2.37.2
>