From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Christoph Hellwig <hch@infradead.org>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Andrew Morton <akpm@linux-foundation.org>,
Jann Horn <jannh@google.com>, Eric Biggers <ebiggers3@gmail.com>,
Elena Reshetova <elena.reshetova@intel.com>,
Hans Liljestrand <ishkamiel@gmail.com>,
Greg KH <gregkh@linuxfoundation.org>,
Alexey Dobriyan <adobriyan@gmail.com>,
"Serge E. Hallyn" <serge@hallyn.com>,
arozansk@redhat.com, Davidlohr Bueso <dave@stgolabs.net>,
Manfred Spraul <manfred@colorfullife.com>,
"axboe@kernel.dk" <axboe@kernel.dk>,
James Bottomley <James.Bottomley@hansenpartnership.com>,
"x86@kernel.org" <x86@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
"David S. Miller" <davem@davemloft.net>,
Rik van Riel <riel@redhat.com>,
LKML <linux-kernel@vger.kernel.org>,
linux-arch <linux-arch@vger.kernel.org>,
"kernel-hardening@lists.openwall.com"
<kernel-hardening@lists.openwall.com>
Subject: Re: [PATCH v6 2/2] x86/refcount: Implement fast refcount overflow protection
Date: Wed, 19 Jul 2017 18:30:24 -0500 [thread overview]
Message-ID: <20170719233024.nt5yr5xoc5woelbk@treble> (raw)
In-Reply-To: <CAGXu5j+EkpmO2tB71n9rEjb_6GfWza3qBLUDTuhjZwnAYTX5WA@mail.gmail.com>
On Wed, Jul 19, 2017 at 04:12:37PM -0700, Kees Cook wrote:
> On Wed, Jul 19, 2017 at 12:37 PM, Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> > +#define ASM_UNREACHABLE \
> > + "999: .pushsection .discard.unreachable\n\t" \
> > + ".long 999b - .\n\t" \
> > + ".popsection\n\t"
>
> Will this end up running into the same bug fixed with
> 3d1e236022cc1426b0834565995ddee2ca231cee and the __LINE__ macro? I
> could tell under which conditions gcc would do this kind of merging...
I hope not, but objtool should complain about it if it does.
We could involve the __LINE__ macro, or some other way to make the
labels unique, but that might complicate the code a bit, so we can delay
doing that unless necessary.
--
Josh
next prev parent reply other threads:[~2017-07-19 23:30 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-19 0:03 [PATCH v6 0/2] x86: Implement fast refcount overflow protection Kees Cook
2017-07-19 0:03 ` [PATCH v6 1/2] x86/asm: Add suffix macro for GEN_*_RMWcc() Kees Cook
2017-07-19 0:03 ` [PATCH v6 2/2] x86/refcount: Implement fast refcount overflow protection Kees Cook
2017-07-19 19:37 ` Josh Poimboeuf
2017-07-19 19:45 ` Kees Cook
2017-07-19 19:52 ` Josh Poimboeuf
2017-07-19 22:50 ` Kees Cook
2017-07-19 23:01 ` Josh Poimboeuf
2017-07-19 23:12 ` Kees Cook
2017-07-19 23:30 ` Josh Poimboeuf [this message]
2017-07-20 9:11 ` [PATCH v6 0/2] x86: " Ingo Molnar
2017-07-20 17:15 ` Kees Cook
2017-07-20 22:53 ` Kees Cook
2017-07-21 7:50 ` Ingo Molnar
2017-07-21 21:22 ` Andrew Morton
2017-07-22 3:33 ` Kees Cook
2017-07-24 6:38 ` Michael Ellerman
2017-07-24 8:44 ` Peter Zijlstra
2017-07-24 12:09 ` Michael Ellerman
2017-07-24 12:23 ` Peter Zijlstra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20170719233024.nt5yr5xoc5woelbk@treble \
--to=jpoimboe@redhat.com \
--cc=James.Bottomley@hansenpartnership.com \
--cc=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=arozansk@redhat.com \
--cc=axboe@kernel.dk \
--cc=dave@stgolabs.net \
--cc=davem@davemloft.net \
--cc=ebiederm@xmission.com \
--cc=ebiggers3@gmail.com \
--cc=elena.reshetova@intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=hch@infradead.org \
--cc=ishkamiel@gmail.com \
--cc=jannh@google.com \
--cc=keescook@chromium.org \
--cc=kernel-hardening@lists.openwall.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=manfred@colorfullife.com \
--cc=mingo@kernel.org \
--cc=peterz@infradead.org \
--cc=riel@redhat.com \
--cc=serge@hallyn.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).