From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] ipv4: better IP_MAX_MTU enforcement
Date: Wed, 16 Aug 2017 16:29:25 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 16 Aug 2017 11:09:12 -0700

> From: Eric Dumazet <edumazet@google.com>
> 
> While working on yet another syzkaller report, I found
> that our IP_MAX_MTU enforcements were not properly done.
> 
> gcc seems to reload dev->mtu for min(dev->mtu, IP_MAX_MTU), and
> final result can be bigger than IP_MAX_MTU :/
> 
> This is a problem because device mtu can be changed on other cpus or
> threads.
> 
> While this patch does not fix the issue I am working on, it is
> probably worth addressing it.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Also applied and queued up for -stable.

Thanks.