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In-Reply-To: <87sgr9gsiq.fsf@xmission.com>
From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sat, 13 Jul 2019 22:02:15 -0700
Message-ID: <CAHk-=wjTmLQuByQmd1-bqN+piBaEMiJCjwLQOXqO5A+mffTwpQ@mail.gmail.com>
Subject: Re: [PATCH] proc: revert /proc/*/cmdline rewrite
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Alexey Dobriyan <adobriyan@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Alexey Izbyshev <izbyshev@ispras.ru>,
        Oleg Nesterov <oleg@redhat.com>,
        Michal Kubecek <mkubecek@suse.cz>, shasta@toxcorp.com,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        Security Officers <security@kernel.org>
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[ Apparently this thread wasn't on the lists, and I didn't even
notice. So re-sending the patches ]

On Sat, Jul 13, 2019 at 9:16 PM Eric W. Biederman <ebiederm@xmission.com> wrote:
> Given that this fixes a regression and a bug.
>
> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>

I'd much rather start from scratch. Like the attached.

Alexey Izbyshev has a third patch that then limits the setproctitle()
case to only allow looking into the env[] area, which looks
reasonable.

           Linus

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