[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <202002061331.E5956EA@keescook>
Date: Thu, 6 Feb 2020 13:32:48 -0800
From: Kees Cook <keescook@...omium.org>
To: Arvind Sankar <nivedita@...m.mit.edu>
Cc: Kristen Carlson Accardi <kristen@...ux.intel.com>, tglx@...utronix.de,
mingo@...hat.com, bp@...en8.de, hpa@...or.com,
arjan@...ux.intel.com, rick.p.edgecombe@...el.com, x86@...nel.org,
linux-kernel@...r.kernel.org, kernel-hardening@...ts.openwall.com
Subject: Re: [RFC PATCH 11/11] x86/boot: Move "boot heap" out of .bss
On Thu, Feb 06, 2020 at 09:25:59AM -0500, Arvind Sankar wrote:
> On Thu, Feb 06, 2020 at 03:13:12AM -0800, Kees Cook wrote:
> > Yes, thank you for the reminder. I couldn't find the ZO_INIT_SIZE when I
> > was staring at this, since I only looked around the compressed/ directory.
> > :)
> >
>
> There's another thing I noticed -- you would need to ensure that the
> init_size in the header covers your boot heap even if you did split it
> out. The reason is that the bootloader will only know to reserve enough
> memory for init_size: it's possible it might put the initrd or something
> else following the kernel, or theoretically there might be reserved
> memory regions or the end of physical RAM immediately following, so you
> can't assume that area will be available when you get to extract_kernel.
Yeah, that's what I was worrying about after I wrote that patch. Yours
is the correct solution. :) (I Acked both of those now).
--
Kees Cook
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
