From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] net: mangle zero checksum in skb_checksum_help()
Date: Mon, 31 Oct 2016 15:29:32 -0400 (EDT)
Message-ID: <20161031.152932.840383254132956388.davem@davemloft.net>
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sat, 29 Oct 2016 11:02:36 -0700

> From: Eric Dumazet <edumazet@google.com>
> 
> Sending zero checksum is ok for TCP, but not for UDP.
> 
> UDPv6 receiver should by default drop a frame with a 0 checksum,
> and UDPv4 would not verify the checksum and might accept a corrupted
> packet.
> 
> Simply replace such checksum by 0xffff, regardless of transport.
> 
> This error was caught on SIT tunnels, but seems generic.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied and queued up for -stable, thanks.