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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 15 Aug 2018 10:45:36 -0700
Message-ID: <CA+55aFz4J+B7jvxVAGkjdsDJQff46WU2oo00_HaktncFigmxmA@mail.gmail.com>
Subject: Re: [PATCH] Fix kexec forbidding kernels signed with custom platform
 keys to boot
To:     yannik@sembritzki.me
Cc:     David Howells <dhowells@redhat.com>,
        Vivek Goyal <vgoyal@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Peter Anvin <hpa@zytor.com>,
        "the arch/x86 maintainers" <x86@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Wed, Aug 15, 2018 at 10:27 AM Yannik Sembritzki <yannik@sembritzki.me> wrote:
>
> Would this be okay?

No, I meant that it would have to go into the proper header files, and
also be used by verify_pkcs7_signature() and pkcs7_preparse() etc, so
that you could actually grep for this, and understand what it does.

Right now you have to know about the magic. Or follow the call chain
down and look, like I did.

Side note, it should probably be

  #define TRUST_FULL_KEYRING ((struct key *)1ul)

instead, so that it is also type-safe (using "void *" means that it
would work almost anywhere, but it really should be a "struct key *".

And I'd like to see a comment from the kexec people too, I guess.

             Linus