[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAGXu5jJ1rPmb_fs=iN5x6fTMtew8+jxrb=VxQQwiPLYzjxE07g@mail.gmail.com>
Date: Wed, 2 May 2018 14:02:22 -0700
From: Kees Cook <keescook@...omium.org>
To: Thomas Gleixner <tglx@...utronix.de>
Cc: Dave Hansen <dave.hansen@...ux.intel.com>,
Linus Torvalds <torvalds@...ux-foundation.org>, Alexander Popov <alex.popov@...ux.com>,
Kernel Hardening <kernel-hardening@...ts.openwall.com>, PaX Team <pageexec@...email.hu>,
Brad Spengler <spender@...ecurity.net>, Ingo Molnar <mingo@...nel.org>,
Andy Lutomirski <luto@...nel.org>, Tycho Andersen <tycho@...ho.ws>, Laura Abbott <labbott@...hat.com>,
Mark Rutland <mark.rutland@....com>, Ard Biesheuvel <ard.biesheuvel@...aro.org>,
Borislav Petkov <bp@...en8.de>, Richard Sandiford <richard.sandiford@....com>,
"H . Peter Anvin" <hpa@...or.com>, Peter Zijlstra <a.p.zijlstra@...llo.nl>,
"Dmitry V . Levin" <ldv@...linux.org>, Emese Revfy <re.emese@...il.com>, Jonathan Corbet <corbet@....net>,
Andrey Ryabinin <aryabinin@...tuozzo.com>,
"Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>, Thomas Garnier <thgarnie@...gle.com>,
Andrew Morton <akpm@...ux-foundation.org>, Alexei Starovoitov <ast@...nel.org>, Josef Bacik <jbacik@...com>,
Masami Hiramatsu <mhiramat@...nel.org>, Nicholas Piggin <npiggin@...il.com>,
Al Viro <viro@...iv.linux.org.uk>, "David S . Miller" <davem@...emloft.net>,
Ding Tianhong <dingtianhong@...wei.com>, David Woodhouse <dwmw@...zon.co.uk>,
Josh Poimboeuf <jpoimboe@...hat.com>, Steven Rostedt <rostedt@...dmis.org>,
Dominik Brodowski <linux@...inikbrodowski.net>, Juergen Gross <jgross@...e.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Dan Williams <dan.j.williams@...el.com>,
Mathias Krause <minipli@...glemail.com>, Vikas Shivappa <vikas.shivappa@...ux.intel.com>,
Kyle Huey <me@...ehuey.com>, Dmitry Safonov <dsafonov@...tuozzo.com>,
Will Deacon <will.deacon@....com>, Arnd Bergmann <arnd@...db.de>, Florian Weimer <fweimer@...hat.com>,
Boris Lukashev <blukashev@...pervictus.com>, X86 ML <x86@...nel.org>,
LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v11 2/6] x86/entry: Add STACKLEAK erasing the kernel stack
at the end of syscalls
On Wed, May 2, 2018 at 5:51 AM, Kees Cook <keescook@...omium.org> wrote:
> On Wed, May 2, 2018 at 5:39 AM, Thomas Gleixner <tglx@...utronix.de> wrote:
>> On Wed, 2 May 2018, Kees Cook wrote:
>>> On Wed, May 2, 2018 at 1:42 AM, Thomas Gleixner <tglx@...utronix.de> wrote:
>>> > On Mon, 30 Apr 2018, Kees Cook wrote:
>>> >
>>> >> On Mon, Apr 23, 2018 at 9:23 PM, Dave Hansen
>>> >> <dave.hansen@...ux.intel.com> wrote:
>>> >> > Hi Alexander,
>>> >> >
>>> >> > You can add:
>>> >> >
>>> >> > Reviewed-by: Dave Hansen <dave.hansen@...ux.intel.com>
>>> >> >
>>> >> > for this patch if you like. I haven't taken a super close look at the
>>> >> > rest, but this is certainly minimally invasive from my point of view for
>>> >> > the entry code. Thanks, again for reworking it.
>>> >>
>>> >> Thanks Dave!
>>> >>
>>> >> Given this improvement and your review, I'm going to start carrying
>>> >> this for linux-next. Linus, if you're still opposed to this even after
>>> >> the changes here in v11, please let us know. I'd rather hash things
>>> >> out now instead of during a NAK in the 4.18 merge window. :)
>>> >
>>> > Kees, can we please route that x86/entry stuff through tip to avoid
>>> > conflicts as there are other changes in that area on the horizon.
>>>
>>> Sure, let me figure out how best to split up the patches, since it
>>> touch x86/entry, gcc-plugins, and lkdtm. Thanks!
>>
>> Are they independent or do they carry dependencies?
>
> They carry dependencies, as it interacts with the gcc plugin (and
> lkdtm). As I don't have other plugin changes for 4.18 queued, you
> could take the whole series for x86/entry if you want? Otherwise I can
> try to split out the x86 change so it's more self-contained.
The best way to do this would be to add the x86 entry changes without
CONFIG_GCC_PLUGIN_STACKLEAK, which leaves the results not
compile-testable. Alternatively, if you carried everything, it'd be
weird too, with arm64 coming (which has small changes to the plugin).
I think it'd be better for this to go via my tree with your Ack (where
I can carry the plugin, lkdtm, x86, and arm64 changes). How does that
sound?
-Kees
--
Kees Cook
Pixel Security
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.
