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Date:   Tue, 25 Oct 2022 16:02:22 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Cong Wang <xiyou.wangcong@gmail.com>
Cc:     netdev@vger.kernel.org, Cong Wang <cong.wang@bytedance.com>,
        shaozhengchao <shaozhengchao@huawei.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Tom Herbert <tom@herbertland.com>,
        Eric Dumazet <edumazet@google.com>
Subject: Re: [Patch net] kcm: fix a race condition in kcm_recvmsg()
Message-ID: <20221025160222.5902e899@kernel.org>
In-Reply-To: <20221023023044.149357-1-xiyou.wangcong@gmail.com>
References: <20221023023044.149357-1-xiyou.wangcong@gmail.com>
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On Sat, 22 Oct 2022 19:30:44 -0700 Cong Wang wrote:
> +			spin_lock_bh(&mux->rx_lock);
>  			KCM_STATS_INCR(kcm->stats.rx_msgs);
>  			skb_unlink(skb, &sk->sk_receive_queue);
> +			spin_unlock_bh(&mux->rx_lock);

Why not switch to __skb_unlink() at the same time?
Abundance of caution?

Adding Eric who was fixing KCM bugs recently.