From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: kernel BUG at net/core/skbuff.c:LINE! (2)
Date: Sat, 09 Dec 2017 21:12:21 -0800
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Cc: syzbot
        <bot+ed0838d0fa4c4f2b528e20286e6dc63effc7c14d@syzkaller.appspotmail.com>,
        davem <davem@davemloft.net>, kuznet <kuznet@ms2.inr.ac.ru>,
        LKML <linux-kernel@vger.kernel.org>, linux-sctp@vger.kernel.org,
        network dev <netdev@vger.kernel.org>,
        Neil Horman <nhorman@tuxdriver.com>,
        syzkaller-bugs@googlegroups.com,
        Vlad Yasevich <vyasevich@gmail.com>,
        yoshfuji <yoshfuji@linux-ipv6.org>
To: Xin Long <lucien.xin@gmail.com>,
        Cong Wang <xiyou.wangcong@gmail.com>
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On Sun, 2017-12-10 at 12:38 +0800, Xin Long wrote:
> On Sun, Dec 10, 2017 at 3:36 AM, Cong Wang <xiyou.wangcong@gmail.com>
> wrote:
> > On Fri, Dec 8, 2017 at 12:45 AM, Xin Long <lucien.xin@gmail.com>
> > wrote:
> > > This isn't a sctp problem, but mld's, seems when lo's mtu became
> > > 0,
> > > it allocs a skb without enough space in add_grec():
> > 
> > Shouldn't we just set its min_mtu to ETH_MIN_MTU?
> 
> No idea why there's no min_mtu limitation for lo dev.

Because it wont solve this bug.

ETH_MIN_MTU is really about IPv4.