live-patching.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Kees Cook <keescook@chromium.org>
Cc: Miroslav Benes <mbenes@suse.cz>,
	Kristen Carlson Accardi <kristen@linux.intel.com>,
	tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
	arjan@linux.intel.com, x86@kernel.org,
	linux-kernel@vger.kernel.org,
	kernel-hardening@lists.openwall.com, rick.p.edgecombe@intel.com,
	live-patching@vger.kernel.org
Subject: Re: [PATCH v4 00/10] Function Granular KASLR
Date: Wed, 22 Jul 2020 11:07:30 -0500	[thread overview]
Message-ID: <20200722160730.cfhcj4eisglnzolr@treble> (raw)
In-Reply-To: <202007220738.72F26D2480@keescook>

On Wed, Jul 22, 2020 at 07:39:55AM -0700, Kees Cook wrote:
> On Wed, Jul 22, 2020 at 11:27:30AM +0200, Miroslav Benes wrote:
> > Let me CC live-patching ML, because from a quick glance this is something 
> > which could impact live patching code. At least it invalidates assumptions 
> > which "sympos" is based on.
> 
> In a quick skim, it looks like the symbol resolution is using
> kallsyms_on_each_symbol(), so I think this is safe? What's a good
> selftest for live-patching?

The problem is duplicate symbols.  If there are two static functions
named 'foo' then livepatch needs a way to distinguish them.

Our current approach to that problem is "sympos".  We rely on the fact
that the second foo() always comes after the first one in the symbol
list and kallsyms.  So they're referred to as foo,1 and foo,2.

-- 
Josh


  parent reply	other threads:[~2020-07-22 16:07 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20200717170008.5949-1-kristen@linux.intel.com>
2020-07-22  9:27 ` [PATCH v4 00/10] Function Granular KASLR Miroslav Benes
2020-07-22 14:39   ` Kees Cook
2020-07-22 14:51     ` Joe Lawrence
2020-07-22 14:56       ` Joe Lawrence
2020-07-22 18:24         ` Kristen Carlson Accardi
2020-07-22 16:07     ` Josh Poimboeuf [this message]
2020-07-22 19:42       ` Kees Cook
2020-07-22 19:56         ` Kristen Carlson Accardi
2020-07-22 21:33           ` Josh Poimboeuf
2020-08-21 23:02             ` Kristen Carlson Accardi
2020-08-25 16:16               ` Joe Lawrence
2020-08-28 10:21               ` Miroslav Benes
2020-08-28 19:24                 ` Josh Poimboeuf
2021-01-23 22:59                   ` Fangrui Song
2021-01-25 17:21                     ` Josh Poimboeuf
2020-08-03 11:39   ` Evgenii Shatokhin
2020-08-03 17:45     ` Kees Cook
2020-08-03 18:17       ` Joe Lawrence
2020-08-03 19:38         ` Frank Ch. Eigler
2020-08-03 20:11           ` Kees Cook
2020-08-03 21:12             ` Frank Ch. Eigler
2020-08-03 21:41               ` Kees Cook
2020-08-04  0:48                 ` Frank Ch. Eigler
2020-08-04 17:04         ` Jessica Yu
2020-08-04 18:23 ` Joe Lawrence
2020-08-07 16:38   ` Kristen Carlson Accardi
2020-08-07 17:20     ` Kees Cook
2020-08-10 16:10       ` Kristen Carlson Accardi
2020-08-12 17:18   ` Kristen Carlson Accardi

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=20200722160730.cfhcj4eisglnzolr@treble \
    --to=jpoimboe@redhat.com \
    --cc=arjan@linux.intel.com \
    --cc=bp@alien8.de \
    --cc=keescook@chromium.org \
    --cc=kernel-hardening@lists.openwall.com \
    --cc=kristen@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=live-patching@vger.kernel.org \
    --cc=mbenes@suse.cz \
    --cc=mingo@redhat.com \
    --cc=rick.p.edgecombe@intel.com \
    --cc=tglx@linutronix.de \
    --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).