kernel-hardening - Re: [PATCH 2/2] arm: apply more __ro_after

Follow @Openwall on Twitter for new release announcements and other news

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20160603215404.GA1785@kroah.com>
Date: Fri, 3 Jun 2016 14:54:04 -0700
From: Greg KH <gregkh@...uxfoundation.org>
To: Kees Cook <keescook@...omium.org>
Cc: "kernel-hardening@...ts.openwall.com" <kernel-hardening@...ts.openwall.com>,
	linux-arch <linux-arch@...r.kernel.org>,
	LKML <linux-kernel@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" <linux-arm-kernel@...ts.infradead.org>,
	"x86@...nel.org" <x86@...nel.org>,
	Ard Biesheuvel <ard.biesheuvel@...aro.org>,
	Mathias Krause <minipli@...glemail.com>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH 2/2] arm: apply more __ro_after_init

On Fri, Jun 03, 2016 at 02:26:54PM -0700, Kees Cook wrote:
> On Fri, Jun 3, 2016 at 11:51 AM, Greg KH <gregkh@...uxfoundation.org> wrote:
> > On Fri, Jun 03, 2016 at 11:40:24AM -0700, Kees Cook wrote:
> >> Guided by grsecurity's analogous __read_only markings in arch/arm,
> >> this applies several uses of __ro_after_init to structures that are
> >> only updated during __init.
> >>
> >> Signed-off-by: Kees Cook <keescook@...omium.org>
> >> ---
> >>  arch/arm/kernel/cpuidle.c |  2 +-
> >>  arch/arm/kernel/setup.c   | 10 +++++-----
> >>  arch/arm/kernel/smp.c     |  2 +-
> >>  arch/arm/lib/delay.c      |  2 +-
> >>  arch/arm/mm/mmu.c         |  9 ++-------
> >>  arch/x86/mm/ioremap.c     |  3 +--
> >
> > I don't think this x86 file is an arm-specific one :)
> 
> Hah, whooops. :)
> 
> > That minor nit aside, these patches are a great step forward, are you
> > going to take them and work to push them upstream, or do you want/need
> > others to do this?
> 
> I'll collect more like these and carry a tree for -next and push them for v4.8.

Sounds good!

Is there any "problem" with applying these markings to code that could
be built as a module?  I'm thinking of lots of buses and drivers that
have structures like this, but can be a module or not, depending on the
configuration selected.  It would be nice to get the "benefit" of
protection if the code is built into the kernel image.

thanks,

greg k-h

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.