mptcp: Initialize tcp_rtx_queue when creating a new socket

When we clone from the meta-sk, it may have data in the rtx-queue. So,
we need to reinitialize it for the subflows as they need a clean
rtx-queue.

Also, move the out_of_order_queue initialization to
tcp_create_openreq_child, to have all of it in one place.

Fixes: c61bc63 ("Merge tag 'v4.15-rc3' into mptcp_trunk")
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>

net/ipv4/tcp_minisocks.c

@@ -501,6 +501,8 @@ struct sock *tcp_create_openreq_child(const struct sock *sk,
 		newtp->snd_sml = newtp->snd_una =
 		newtp->snd_nxt = newtp->snd_up = treq->snt_isn + 1;
 
+		newtp->out_of_order_queue = RB_ROOT;
+		newsk->tcp_rtx_queue = RB_ROOT;
 		INIT_LIST_HEAD(&newtp->tsq_node);
 		INIT_LIST_HEAD(&newtp->tsorted_sent_queue);
 

net/mptcp/mptcp_ctrl.c

@@ -1204,6 +1204,7 @@ static int mptcp_alloc_mpcb(struct sock *meta_sk, __u64 remote_key,
 	/* Initialize the queues */
 	skb_queue_head_init(&mpcb->reinject_queue);
 	master_tp->out_of_order_queue = RB_ROOT;
+	master_sk->tcp_rtx_queue = RB_ROOT;
 	INIT_LIST_HEAD(&master_tp->tsq_node);
 	INIT_LIST_HEAD(&master_tp->tsorted_sent_queue);
 
@@ -2171,7 +2172,6 @@ struct sock *mptcp_check_req_child(struct sock *meta_sk,
 	child_tp->mptcp->init_rcv_wnd = req->rsk_rcv_wnd;
 
 	child->sk_tsq_flags = 0;
-	child_tp->out_of_order_queue = RB_ROOT;
 
 	sock_rps_save_rxhash(child, skb);
 	tcp_synack_rtt_meas(child, req);