From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [Bug 14470] New: freez in TCP stack
Date: Thu, 29 Oct 2009 01:00:09 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 29 Oct 2009 06:59:41 +0100

> [PATCH] tcp: clear retrans hints in tcp_send_synack()
> 
> There is a small possibility the skb we unlink from write queue 
> is still referenced by retrans hints.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

So, this would only be true if we were dealing with a data
packet here.  We're not, this is a SYN+ACK which happens to
be cloned in the write queue.

The hint SKBs pointers can only point to real data packets.

And we're only dealing with data packets once we enter established
state, and when we enter established by definition we have unlinked
and freed up any SYN and SYN+ACK SKBs in the write queue.