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Date:   Sat, 18 Apr 2020 01:00:38 +0200
From:   Stefano Brivio <sbrivio@redhat.com>
To:     Hillf Danton <hdanton@sina.com>
Cc:     Florian Westphal <fw@strlen.de>,
        syzbot <syzbot+33e06702fd6cffc24c40@syzkaller.appspotmail.com>,
        coreteam@netfilter.org, davem@davemloft.net, kadlec@netfilter.org,
        kuba@kernel.org, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, netfilter-devel@vger.kernel.org,
        pablo@netfilter.org, syzkaller-bugs@googlegroups.com
Subject: Re: WARNING in nf_nat_unregister_fn
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In-Reply-To: <20200417213348.GC32392@breakpoint.cc>
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 <20200417094250.21872-1-hdanton@sina.com>
 <20200417213348.GC32392@breakpoint.cc>
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Hillf,

On Fri, 17 Apr 2020 23:33:48 +0200
Florian Westphal <fw@strlen.de> wrote:

> Hillf Danton <hdanton@sina.com> wrote:
> > In case of failure to register NFPROTO_IPV4, unregister NFPROTO_IPV6
> > instead of ops->pf (== NFPROTO_INET).

Note that the patch you sent didn't reach any list you probably sent it
to (netfilter-devel, netdev, lkml). I'm seeing it just because Florian
answered.

This is probably the same issue we had with your openvswitch patch last
year. By the way, the IP address you used last time is now reported as
being "blocked" by:

	zen.spamhaus.org
	pbl.spamhaus.org

I guess vger might filter using Spamhaus lists (including their "PBL"),
which won't let your email through if you're running a mail server with
an dynamic IP address.

I don't support this practice, but this might be the issue. You can
quickly get an overview of blacklists your address might be on at e.g.:
	http://www.anti-abuse.org/

-- 
Stefano