From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sun, 10 Dec 2017 05:12:21 +0000
Subject: Re: kernel BUG at net/core/skbuff.c:LINE! (2)
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To: Xin Long <lucien.xin@gmail.com>, Cong Wang <xiyou.wangcong@gmail.com>
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>

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.