Re: [PATCH net] net: avoid skb_warn_bad_offload false positives on UFO

[David Miller <davem@davemloft.net>]

From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Date: Tue,  8 Aug 2017 14:22:55 -0400

> From: Willem de Bruijn <willemb@google.com>
> 
> skb_warn_bad_offload triggers a warning when an skb enters the GSO
> stack at __skb_gso_segment that does not have CHECKSUM_PARTIAL
> checksum offload set.
> 
> Commit b2504a5dbef3 ("net: reduce skb_warn_bad_offload() noise")
> observed that SKB_GSO_DODGY producers can trigger the check and
> that passing those packets through the GSO handlers will fix it
> up. But, the software UFO handler will set ip_summed to
> CHECKSUM_NONE.
> 
> When __skb_gso_segment is called from the receive path, this
> triggers the warning again.
> 
> Make UFO set CHECKSUM_UNNECESSARY instead of CHECKSUM_NONE. On
> Tx these two are equivalent. On Rx, this better matches the
> skb state (checksum computed), as CHECKSUM_NONE here means no
> checksum computed.
> 
> See also this thread for context:
> http://patchwork.ozlabs.org/patch/799015/
> 
> Fixes: b2504a5dbef3 ("net: reduce skb_warn_bad_offload() noise")
> Signed-off-by: Willem de Bruijn <willemb@google.com>

Applied and queued up for -stable, thank you.