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Date:   Thu, 10 Nov 2022 22:15:44 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Pedro Falcato <pedro.falcato@gmail.com>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org, dalias@libc.org,
        ebiederm@xmission.com, sam@gentoo.org, viro@zeniv.linux.org.uk
Subject: Re: [PATCH v3] fs/binfmt_elf: Fix memsz > filesz handling
Message-ID: <202211102214.D764FAE21@keescook>
References: <20221108110715.227062-1-pedro.falcato@gmail.com>
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 <CAKbZUD2r=zK91J4c6pyHQhDuqqMzmrx+BBgFF4Cso2jK+jjhHA@mail.gmail.com>
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On Fri, Nov 11, 2022 at 03:59:08AM +0000, Pedro Falcato wrote:
> We could of course also just sort the program headers at load time,
> but I assume that's unwanted overhead for most well behaved ELF
> program headers :)

Large refactoring of the ELF loader needs proper unit testing, and we're
still a bit away from that existing. In the meantime, we'll need to make
very very small changes to fix bugs. I've sent a minimal change which I
think should fix the problem (now at v2 since right after sending it I
realized I was trading one accidentally correct state for another in the
v1):
https://lore.kernel.org/linux-hardening/20221111061315.gonna.703-kees@kernel.org/

-- 
Kees Cook