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Date:   Thu, 17 Mar 2022 11:53:19 -0700
From:   Kees Cook <keescook@chromium.org>
To:     James Jones <linux@theinnocuous.com>
Cc:     Arnd Bergmann <arnd@arndb.de>, Borislav Petkov <bp@alien8.de>,
        the arch/x86 maintainers <x86@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] x86: Remove a.out support
Message-ID: <202203171152.F35EB19767@keescook>
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On Thu, Mar 17, 2022 at 02:04:46AM +0000, James Jones wrote:
> On 3/16/22 3:30 PM, Kees Cook wrote:
> > On Wed, Mar 16, 2022 at 01:38:31PM +0100, Arnd Bergmann wrote:
> >> is in the end, but it's likely easier than a standalone a.out loader
> >> in user space, or a conversion to ELF format.
> >
> > Yeah, the exec format is really simple. The only tricky bit was preparing
> > the stack and making sure everything landed in the right place for text
> > and data. James, can you try this? aln and mac run for me, but I'm not
> > actually exercising them beyond dumping argument lists, etc:
> >
> > https://github.com/kees/kernel-tools/tree/trunk/a.out
> 
> Yes, works perfectly, thank you. I like the idea of using this much

Hurray!

> better than getting emailed every time someone wants to delete the a.out
> code again. Consider my use case withdrawn. I've already pushed an
> update to my jaguar-sdk project to use this tool instead.

Nice; I see there are other binaries besides aln and mac that are
working with this too? *whew* I'm glad it was relatively straight
forward. :)

-- 
Kees Cook