From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [RFC PATCH] kcm: hold rx mux lock when updating the receive
 queue.
Date: Tue, 05 Jun 2018 10:53:35 -0400 (EDT)
Message-ID: <20180605.105335.458709382920337752.davem@davemloft.net>
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From: Paolo Abeni <pabeni@redhat.com>
Date: Tue,  5 Jun 2018 12:32:33 +0200

> @@ -1157,7 +1158,9 @@ static int kcm_recvmsg(struct socket *sock, struct msghdr *msg,
>  			/* Finished with message */
>  			msg->msg_flags |= MSG_EOR;
>  			KCM_STATS_INCR(kcm->stats.rx_msgs);
> +			spin_lock_bh(&kcm->mux->rx_lock);
>  			skb_unlink(skb, &sk->sk_receive_queue);
> +			spin_unlock_bh(&kcm->mux->rx_lock);

Hmmm, maybe I don't understand the corruption.

But, skb_unlink() takes the sk->sk_receive_queue.lock which should
prevent SKB list corruption.