linux-kernel - Re: [PATCH] Fix kexec forbidding kernels signed with custom platform keys to boot

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Date:   Wed, 15 Aug 2018 09:54:34 -0700
From:   Linus Torvalds <torvalds@...ux-foundation.org>
To:     yannik@...britzki.me, David Howells <dhowells@...hat.com>,
        Vivek Goyal <vgoyal@...hat.com>
Cc:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Peter Anvin <hpa@...or.com>,
        "the arch/x86 maintainers" <x86@...nel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] Fix kexec forbidding kernels signed with custom platform
 keys to boot

This needs more people involved, and at least a sign-off.

It looks ok, but I think we need a #define for the magical (void *)1UL
thing. I see the use in verify_pkcs7_signature(), but still.

              Linus



On Wed, Aug 15, 2018 at 3:11 AM Yannik Sembritzki <yannik@...britzki.me> wrote:
>
> ---
>  arch/x86/kernel/kexec-bzimage64.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
> index 7326078e..eaaa125d 100644
> --- a/arch/x86/kernel/kexec-bzimage64.c
> +++ b/arch/x86/kernel/kexec-bzimage64.c
> @@ -532,7 +532,7 @@ static int bzImage64_cleanup(void *loader_data)
>  static int bzImage64_verify_sig(const char *kernel, unsigned long kernel_len)
>  {
>         return verify_pefile_signature(kernel, kernel_len,
> -                                      NULL,
> +                                      (void *)1UL,
>                                        VERIFYING_KEXEC_PE_SIGNATURE);
>  }
>  #endif
> --
> 2.17.1
>
> The exact scenario under which this issue occurs is described here:
> https://bugzilla.redhat.com/show_bug.cgi?id=1554113
>