From mboxrd@z Thu Jan  1 00:00:00 1970
From: Soheil Hassas Yeganeh <soheil.kdev@gmail.com>
Subject: Re: [PATCH net-next] tcp: tcp_fragment() should not assume rtx skbs
Date: Thu, 2 Nov 2017 22:33:26 -0400
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Cc: Eric Dumazet <eric.dumazet@gmail.com>,
        David Miller <davem@davemloft.net>,
        netdev <netdev@vger.kernel.org>,
        Yuchung Cheng <ycheng@google.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Priyaranjan Jha <priyarjha@google.com>
To: Neal Cardwell <ncardwell@google.com>
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On Thu, Nov 2, 2017 at 9:16 PM, Neal Cardwell <ncardwell@google.com> wrote:
> On Thu, Nov 2, 2017 at 9:10 PM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
>> From: Eric Dumazet <edumazet@google.com>
>>
>> While stress testing MTU probing, we had crashes in list_del() that we root-caused
>> to the fact that tcp_fragment() is unconditionally inserting the freshly allocated
>> skb into tsorted_sent_queue list.
>>
>> But this list is supposed to contain skbs that were sent.
>> This was mostly harmless until MTU probing was enabled.
>>
>> Fortunately we can use the tcp_queue enum added later (but in same linux version)
>> for rtx-rb-tree to fix the bug.
>>
>> Fixes: e2080072ed2d ("tcp: new list for sent but unacked skbs for RACK recovery")
>> Signed-off-by: Eric Dumazet <edumazet@google.com>
>
> Acked-by: Neal Cardwell <ncardwell@google.com>

Acked-by: Soheil Hassas Yeganeh <soheil@google.com>

Nice! Thank you, Eric!