From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net v2] ip: fix IP_CHECKSUM handling
Date: Tue, 21 Feb 2017 12:26:26 -0500 (EST)
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From: Paolo Abeni <pabeni@redhat.com>
Date: Tue, 21 Feb 2017 09:33:18 +0100

> The skbs processed by ip_cmsg_recv() are not guaranteed to
> be linear e.g. when sending UDP packets over loopback with
> MSGMORE.
> Using csum_partial() on [potentially] the whole skb len
> is dangerous; instead be on the safe side and use skb_checksum().
> 
> Thanks to syzkaller team to detect the issue and provide the
> reproducer.
> 
> v1 -> v2:
>  - move the variable declaration in a tighter scope
> 
> Fixes: ad6f939ab193 ("ip: Add offset parameter to ip_cmsg_recv")
> Reported-by: Andrey Konovalov <andreyknvl@google.com>
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Applied and queued up for -stable, thanks.