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From:   Xie He <xie.he.0141@gmail.com>
Date:   Mon, 1 Feb 2021 08:14:31 -0800
Message-ID: <CAJht_EOw4d9h7LqOsXpucADV5=gAGws-fKj5q7BdH2+h0Yv9Vg@mail.gmail.com>
Subject: Re: [PATCH net] net: lapb: Copy the skb before sending a packet
To:     Julian Wiedmann <jwi@linux.ibm.com>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Linux X25 <linux-x25@vger.kernel.org>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Martin Schiller <ms@dev.tdt.de>
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On Mon, Feb 1, 2021 at 6:10 AM Julian Wiedmann <jwi@linux.ibm.com> wrote:
>
> This sounds a bit like you want skb_cow_head() ... ?

Calling "skb_cow_head" before we call "skb_clone" would indeed solve
the problem of writes to our clones affecting clones in other parts of
the system. But since we are still writing to the skb after
"skb_clone", it'd still be better to replace "skb_clone" with
"skb_copy" to avoid interference between our own clones.