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From:   Cong Wang <xiyou.wangcong@gmail.com>
Date:   Mon, 27 Jul 2020 12:50:29 -0700
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Subject: Re: [PATCH] [net/ipv6] ip6_output: Add ipv6_pinfo null check
To:     Gaurav Singh <gaurav1086@gmail.com>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Jakub Kicinski <kuba@kernel.org>,
        "open list:NETWORKING [IPv4/IPv6]" <netdev@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
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On Sun, Jul 26, 2020 at 8:39 PM Gaurav Singh <gaurav1086@gmail.com> wrote:
>
> ipv6_pinfo is initlialized by inet6_sk() which returns NULL.

Why? It only returns NULL for timewait or request sock, but
I don't see how ip6_autoflowlabel() could be called on these
sockets. So please explain.

> Hence it can cause segmentation fault. Fix this by adding a
> NULL check.

Which exact call path? Do you have a full stack trace?

Thanks.