From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrey Dmitrov <andrey.dmitrov@oktetlabs.ru>
Subject: Re: TCP connection will hang in FIN_WAIT1 after closing if zero window
 is advertised
Date: Tue, 16 Sep 2014 18:08:15 +0400
Message-ID: <5418444F.7010403@oktetlabs.ru>
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Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>,
	netdev@vger.kernel.org,
	"Alexandra N. Kossovsky" <Alexandra.Kossovsky@oktetlabs.ru>,
	Konstantin Ushakov <kostik@oktetlabs.ru>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On 16/09/14 17:09, Eric Dumazet wrote:
> 1) TCP_USER_TIMEOUT would be the fit for this, but its current
> implementation do not take care of the probes sent, even in FIN_WAIT
> state when in this zero window mode. A patch would be needed.
>
> 2) SO_LINGER, timeout=0 might work.
I tried to set SO_LINGER with non-zero timeout before reporting the bug, 
it did not help. But I've just tried again with the zero timeout 
(l_linger=0) and it works, the connection has been interrupted 
immediately after socket closing, RST packet has been sent. It seems 
like a bug, SO_LINGER with non-zero timeout does not interrupt the 
connection.

Thanks,
Andrey