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Date:   Mon, 10 Jul 2023 16:54:05 +0200
From:   Richard Gobert <richardbgobert@gmail.com>
To:     Eric Dumazet <edumazet@google.com>
Cc:     davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com,
        willemdebruijn.kernel@gmail.com, dsahern@kernel.org,
        tom@herbertland.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, gal@nvidia.com
Subject: Re: [PATCH 1/1] net: gro: fix misuse of CB in udp socket lookup
Message-ID: <20230710145403.GA22009@debian>
References: <20230707121650.GA17677@debian>
 <20230707122627.GA17845@debian>
 <CANn89i+gm=0J3aR_9ikhroQmAvuQ+-dPMH1em9WrmE1o1pfi7w@mail.gmail.com>
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Thanks, I will send a v2 with the fixes.

> ipv6_rcv() inits
> 
> IP6CB(skb)->iif = skb_dst(skb) ?
> ip6_dst_idev(skb_dst(skb))->dev->ifindex : dev->ifindex;
> 
> You chose to always use skb->dev->ifindex instead ?
> 
> You might add a comment why it is okay.

It looks like this assignment ("ip6_dst_idev(skb_dst(skb))->dev->ifindex")
is relevant only in case of sending traffic on loopback.
It does not seem relevant in GRO stack.
That is why I chose to use only the `skb->dev->ifindex` part.
Do you think that's correct?