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Subject: Re: [PATCH v4 00/10] Function Granular KASLR
From:   Joe Lawrence <joe.lawrence@redhat.com>
To:     Kees Cook <keescook@chromium.org>, Miroslav Benes <mbenes@suse.cz>
Cc:     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
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Message-ID: <b5bc7a92-a11e-d75d-eefb-fc640c87490d@redhat.com>
Date:   Wed, 22 Jul 2020 10:56:39 -0400
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On 7/22/20 10:51 AM, Joe Lawrence wrote:
> On 7/22/20 10:39 AM, 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?
>>
> 
> Hi Kees,
> 
> I don't think any of the in-tree tests currently exercise the
> kallsyms/sympos end of livepatching.
> 

On second thought, I mispoke.. The general livepatch code does use it:

klp_init_object
   klp_init_object_loaded
     klp_find_object_symbol

in which case any of the current kselftests should exercise that.

   % make -C tools/testing/selftests/livepatch run_tests

-- Joe