From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsa@cumulusnetworks.com>
Subject: Re: net: heap out-of-bounds in
 fib6_clean_node/rt6_fill_node/fib6_age/fib6_prune_clone
Date: Fri, 21 Apr 2017 12:25:33 -0600
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Cc: Andrey Konovalov <andreyknvl@google.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Cong Wang <xiyou.wangcong@gmail.com>,
        Mahesh Bandewar <maheshb@google.com>,
        Eric Dumazet <edumazet@google.com>,
        David Miller <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        James Morris <jmorris@namei.org>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Patrick McHardy <kaber@trash.net>,
        netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        syzkaller <syzkaller@googlegroups.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On 4/21/17 10:47 AM, Eric Dumazet wrote:
> On Fri, 2017-04-21 at 08:27 -0600, David Ahern wrote:
>> On 4/20/17 10:09 AM, Andrey Konovalov wrote:
>>> On Thu, Apr 20, 2017 at 5:39 PM, Andrey Konovalov <andreyknvl@google.com> wrote:
>>>> On Thu, Apr 20, 2017 at 5:35 PM, David Ahern <dsa@cumulusnetworks.com> wrote:
>>>>> On 4/20/17 9:28 AM, Andrey Konovalov wrote:
>>>>>> This one seems to be much closer to what Dmitry reported intially.
>>>>> does not repro here; I ran in a loop and nothing.
>>> Here's strace log, maybe it'll help figuring out why it doesn't reproduce:
>>
>> reproduced. working on it.
> 
> Thanks guys for working on this ;)
> 


Reliable reproducer is the key.

I see what's going on - why the WARN_ON is hit; just looking for the
right fix.