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Date: Mon, 15 Sep 2014 09:24:41 -0700
From: Randy Dunlap <rdunlap@infradead.org>
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To: Andrey Ryabinin <a.ryabinin@samsung.com>, linux-kernel@vger.kernel.org
CC: Dmitry Vyukov <dvyukov@google.com>, Konstantin Serebryany <kcc@google.com>,
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Subject: Re: [RFC/PATCH v2 01/10] Add kernel address sanitizer infrastructure.
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On 09/15/14 08:28, Andrey Ryabinin wrote:
> On 09/14/2014 05:35 AM, Randy Dunlap wrote:
>> Following sentence is confusing.  I'm not sure how to fix it.
>>
> 
> 
> Perhaps rephrase is like this:
> 
> Do not use slub poisoning with KASan if user tracking enabled (iow slub_debug=PU).

                                       if user tracking is enabled

> User tracking info (allocation/free stacktraces) are stored inside slub object's metadata.
> Slub poisoning overwrites slub object and it's metadata with poison value on freeing.

                                            its

> So if KASan will detect use after free, allocation/free stacktraces will be overwritten

  So if KASan detects a use after free, allocation/free stacktraces are overwritten

> and KASan won't be able to print them.


Thanks.

-- 
~Randy