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Date:   Wed, 16 Mar 2022 09:10:39 -0700
From:   Kees Cook <keescook@chromium.org>
To:     James Jones <linux@theinnocuous.com>
Cc:     bp@alien8.de, x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: Remove a.out support
Message-ID: <202203160909.B1A022B@keescook>
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On Wed, Mar 16, 2022 at 05:06:10AM +0000, James Jones wrote:
> I dug the scripts up in the state they were in when I gave up (September
> 2020 according to mtime), and put them on github in case anyone wants to
> have a go at it:
> 
> https://github.com/cubanismo/aout-to-elf/
> 
> It was an interesting problem in its own right, and I'd be curious to
> know what I missed.

Yeah, this is a good start. I think the main problem is with how program
entry works, specifically that %esp is pointing to argc (with all the
args in memory above there), which isn't the way ELF sets %esp.

It might be possible to make a userspace loader, though. Hmm.

-- 
Kees Cook