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Date:   Mon, 27 Jun 2022 15:20:16 +0500
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Cc:     usama.anjum@collabora.com, "David S. Miller" <davem@davemloft.net>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        David Ahern <dsahern@kernel.org>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Gabriel Krisman Bertazi <krisman@collabora.com>,
        open list <linux-kernel@vger.kernel.org>,
        Collabora Kernel ML <kernel@collabora.com>,
        Paul Gofman <pgofman@codeweavers.com>,
        "open list:NETWORKING [TCP]" <netdev@vger.kernel.org>,
        Sami Farin <hvtaifwkbgefbaei@gmail.com>
Subject: Re: [RFC] EADDRINUSE from bind() on application restart after killing
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To:     Eric Dumazet <edumazet@google.com>
References: <5099dc39-c6d9-115a-855b-6aa98d17eb4b@collabora.com>
 <CANn89i+R9RgmD=AQ4vX1Vb_SQAj4c3fi7-ZtQz-inYY4Sq4CMQ@mail.gmail.com>
 <8eb9b438-7018-4fe3-8be6-bb023df99594@collabora.com>
 <CANn89iJ1DfmuPz5pGdw=j9o+3O4R9tnTNFKi-ppW1O2sfmnN4g@mail.gmail.com>
From:   Muhammad Usama Anjum <usama.anjum@collabora.com>
In-Reply-To: <CANn89iJ1DfmuPz5pGdw=j9o+3O4R9tnTNFKi-ppW1O2sfmnN4g@mail.gmail.com>
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Hi Eric,

On 5/30/22 8:28 PM, Eric Dumazet wrote:
>> The following command and patch work for my use case. The socket in
>> TIME_WAIT_2 or TIME_WAIT state are closed when zapped.
>>
>> Can you please upstream this patch?
> Yes, I will when net-next reopens, thanks for testing it.
Have you tried upstreaming it?

Tested-by: Muhammad Usama Anjum <usama.anjum@collabora.com>

> 
>>> diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
>>> index 9984d23a7f3e1353d2e1fc9053d98c77268c577e..1b7bde889096aa800b2994c64a3a68edf3b62434
>>> 100644
>>> --- a/net/ipv4/tcp.c
>>> +++ b/net/ipv4/tcp.c
>>> @@ -4519,6 +4519,15 @@ int tcp_abort(struct sock *sk, int err)
>>>                         local_bh_enable();
>>>                         return 0;
>>>                 }
>>> +               if (sk->sk_state == TCP_TIME_WAIT) {
>>> +                       struct inet_timewait_sock *tw = inet_twsk(sk);
>>> +
>>> +                       refcount_inc(&tw->tw_refcnt);
>>> +                       local_bh_disable();
>>> +                       inet_twsk_deschedule_put(tw);
>>> +                       local_bh_enable();
>>> +                       return 0;
>>> +               }
>>>                 return -EOPNOTSUPP;
>>>         }

-- 
Muhammad Usama Anjum