From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] ipv4: fix a race in ip4_datagram_release_cb()
Date: Tue, 10 Jun 2014 17:55:28 -0700
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Cc: Alexey Preobrazhensky <preobr@google.com>,
	Steffen Klassert <steffen.klassert@secunet.com>,
	David Miller <davem@davemloft.net>, paulmck@linux.vnet.ibm.com,
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	Dmitry Vyukov <dvyukov@google.com>,
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	Eric Dumazet <edumazet@google.com>,
	Bruce Curtis <brutus@google.com>,
	Maciej =?UTF-8?Q?=C5=BBenczykowski?= <maze@google.com>,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: dormando <dormando@rydia.net>
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On Tue, 2014-06-10 at 17:32 -0700, dormando wrote:

> >
> 
> This is neat. So just confirming that I understand (thanks for re-cc'ing
> me btw <3):
> 
> Because of the UDP glitch, it can cause either the kernel panic in the UDP
> code, but also elsewhere in the TCP stack based on if it's fiddling with
> the same DST being hosed by a UDP packet?
> 
> Unfortunately we're observing a pretty severe sintr cpu increase under
> 3.14, so I'm going to try this on 3.10.latest. Any potential issues there?
> 
> Thankfully it seems like our udpkill utility will reproduce it quickly.
> Lets see how it goes!

This is a start, because we have other bugs of the same kind.

I was working on follow up