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From: Kostya Serebryany <kcc@google.com>
Date: Wed, 9 Aug 2017 13:32:42 -0700
Message-ID: <CAN=P9pgnuYL=PzMFS+KYA173h8BdPZ4UDY4fGN6yvehSk0jhdA@mail.gmail.com>
Subject: Re: new ELF marking
To: "H.J. Lu" <hjl.tools@gmail.com>
Cc: Kees Cook <keescook@google.com>, LKML <linux-kernel@vger.kernel.org>,
        Binutils <binutils@sourceware.org>
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Sender: linux-kernel-owner@vger.kernel.org
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> >
> > I believe this would only be an output bit, but I'm not sure how it
> > would be wired into binutils. Kostya, do you know any details about
> > how AddressSanitizer might be able to create this ELF note?

I don't, hopefully H.J's suggestion works.
Will it be backward compatible?
(i.e. will the binaries built in the new way work on the old kernels?)

Thanks!

--kcc
>
>
> if it is an output only bit, "-z fobar" should work, like
>
>   -z ibt                      Generate GNU_PROPERTY_X86_FEATURE_1_IBT
>   -z shstk                    Generate GNU_PROPERTY_X86_FEATURE_1_SHSTK
>
> Or you can put it in the input file and linker will copy it to output, like
> GNU_PROPERTY_STACK_SIZE.