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From: Doug Anderson <dianders@chromium.org>
Date: Mon, 26 Feb 2024 14:37:29 -0800
Message-ID: <CAD=FV=Vh7Ctaj6N_k9gdkrqpb687zJqQN19qTZXMyDw6TujvLQ@mail.gmail.com>
Subject: Re: [PATCH] proc: allow restricting /proc/pid/mem writes
To: Adrian Ratiu <adrian.ratiu@collabora.com>
Cc: Kees Cook <keescook@chromium.org>, jannh@google.com, 
	linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org, 
	linux-kernel@vger.kernel.org, kernel@collabora.com, 
	Guenter Roeck <groeck@chromium.org>, Mike Frysinger <vapier@chromium.org>, 
	linux-hardening@vger.kernel.org
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Hi,

On Mon, Feb 26, 2024 at 2:33=E2=80=AFPM Adrian Ratiu <adrian.ratiu@collabor=
a.com> wrote:
>
> > > [...]
> > > +config SECURITY_PROC_MEM_RESTRICT_WRITES
> >
> > Instead of a build-time CONFIG, I'd prefer a boot-time config (or a
> > sysctl, but that's be harder given the perms). That this is selectable
> > by distro users, etc, and they don't need to rebuild their kernel to
> > benefit from it.
>
> Ack, I'll implement a cmdline arg in v2.

Any objections to doing both? Have a CONFIG option for a default and a
cmdline to override it? This way if a distro wants to restrict writes
by default then don't need to jam more stuff into the kernel command
line.

-Doug