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Date:   Thu, 24 Oct 2019 03:12:18 +0200
From:   Florian Westphal <fw@strlen.de>
To:     praveen chaudhary <praveen5582@gmail.com>
Cc:     Florian Westphal <fw@strlen.de>, davem@davemloft.net,
        kadlec@netfilter.org, pablo@netfilter.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, Zhenggen Xu <zxu@linkedin.com>,
        Andy Stracner <astracner@linkedin.com>
Subject: Re: [PATCH] [netfilter]: Fix skb->csum calculation when netfilter
 manipulation for NF_NAT_MANIP_SRC\DST is done on IPV6 packet.
Message-ID: <20191024011218.GT25052@breakpoint.cc>
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praveen chaudhary <praveen5582@gmail.com> wrote:
> inet_proto_csum_replace16 is called from many places, whereas this fix is
> applicable only for nf_nat_ipv6_csum_update. where we need to update
> skb->csum for ipv6 src/dst address change.

Under which circumstances does inet_proto_csum_replace16 upate
skb->csum correctly?

> So, I added a new function. Basically, I used a safe approach to fix it,
> without impacting other cases. Let me know other options,  I am open to
> suggestions.

You seem to imply inet_proto_csum_replace16 is fine and only broken for ipv6
nat.