Re: [PATCH] proc: allow restricting /proc/pid/mem writes

From: Doug Anderson <dianders@chromium.org>
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
Subject: Re: [PATCH] proc: allow restricting /proc/pid/mem writes
Date: Mon, 26 Feb 2024 14:37:29 -0800	[thread overview]
Message-ID: <CAD=FV=Vh7Ctaj6N_k9gdkrqpb687zJqQN19qTZXMyDw6TujvLQ@mail.gmail.com> (raw)
In-Reply-To: <1405e4-65dd1180-3-7a785380@32026879>

Hi,

On Mon, Feb 26, 2024 at 2:33 PM Adrian Ratiu <adrian.ratiu@collabora.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