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Date:   Wed, 8 Dec 2021 11:51:13 +0100
From:   Florian Westphal <fw@strlen.de>
To:     David Ahern <dsahern@gmail.com>
Cc:     Andrea Mayer <andrea.mayer@uniroma2.it>,
        Andrea Righi <andrea.righi@canonical.com>,
        "David S. Miller" <davem@davemloft.net>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        David Ahern <dsahern@kernel.org>,
        Jakub Kicinski <kuba@kernel.org>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Ahmed Abdelsalam <ahabdels@gmail.com>,
        Paolo Lungaroni <paolo.lungaroni@uniroma2.it>,
        Stefano Salsano <stefano.salsano@uniroma2.it>
Subject: Re: [PATCH] ipv6: fix NULL pointer dereference in ip6_output()
Message-ID: <20211208105113.GE30918@breakpoint.cc>
References: <20211206163447.991402-1-andrea.righi@canonical.com>
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David Ahern <dsahern@gmail.com> wrote:
> On 12/7/21 5:21 PM, Andrea Mayer wrote:
> > +        IP6CB(skb)->iif = skb->skb_iif;
> >          [...]
> > 
> > What do you think?
> > 
> 
> I like that approach over the need for a fall back in core ipv6 code.

What if the device is removed after ->iif assignment and before dev lookup?