1 files changed, 17 insertions, 28 deletions

diff --git a/net/mptcp/fastopen.c b/net/mptcp/fastopen.c
index d237d142171c..82ec15bcfd7f 100644
--- a/net/mptcp/fastopen.c
+++ b/net/mptcp/fastopen.c
@@ -9,11 +9,18 @@
 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow,
 					      struct request_sock *req)
 {
-	struct sock *ssk = subflow->tcp_sock;
-	struct sock *sk = subflow->conn;
+	struct sock *sk, *ssk;
 	struct sk_buff *skb;
 	struct tcp_sock *tp;
 
+	/* on early fallback the subflow context is deleted by
+	 * subflow_syn_recv_sock()
+	 */
+	if (!subflow)
+		return;
+
+	ssk = subflow->tcp_sock;
+	sk = subflow->conn;
 	tp = tcp_sk(ssk);
 
 	subflow->is_mptfo = 1;
@@ -25,7 +32,8 @@ void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subf
 	/* dequeue the skb from sk receive queue */
 	__skb_unlink(skb, &ssk->sk_receive_queue);
 	skb_ext_reset(skb);
-	skb_orphan(skb);
+
+	mptcp_subflow_lend_fwdmem(subflow, skb);
 
 	/* We copy the fastopen data, but that don't belong to the mptcp sequence
 	 * space, need to offset it in the subflow sequence, see mptcp_subflow_get_map_offset()
@@ -33,41 +41,22 @@ void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subf
 	tp->copied_seq += skb->len;
 	subflow->ssn_offset += skb->len;
 
-	/* initialize a dummy sequence number, we will update it at MPC
-	 * completion, if needed
-	 */
+	/* Only the sequence delta is relevant */
 	MPTCP_SKB_CB(skb)->map_seq = -skb->len;
 	MPTCP_SKB_CB(skb)->end_seq = 0;
 	MPTCP_SKB_CB(skb)->offset = 0;
 	MPTCP_SKB_CB(skb)->has_rxtstamp = TCP_SKB_CB(skb)->has_rxtstamp;
+	MPTCP_SKB_CB(skb)->cant_coalesce = 1;
 
 	mptcp_data_lock(sk);
+	DEBUG_NET_WARN_ON_ONCE(sock_owned_by_user_nocheck(sk));
 
-	mptcp_set_owner_r(skb, sk);
+	mptcp_borrow_fwdmem(sk, skb);
+	skb_set_owner_r(skb, sk);
 	__skb_queue_tail(&sk->sk_receive_queue, skb);
+	mptcp_sk(sk)->bytes_received += skb->len;
 
 	sk->sk_data_ready(sk);
 
 	mptcp_data_unlock(sk);
 }
-
-void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow,
-				   const struct mptcp_options_received *mp_opt)
-{
-	struct sock *sk = (struct sock *)msk;
-	struct sk_buff *skb;
-
-	mptcp_data_lock(sk);
-	skb = skb_peek_tail(&sk->sk_receive_queue);
-	if (skb) {
-		WARN_ON_ONCE(MPTCP_SKB_CB(skb)->end_seq);
-		pr_debug("msk %p moving seq %llx -> %llx end_seq %llx -> %llx", sk,
-			 MPTCP_SKB_CB(skb)->map_seq, MPTCP_SKB_CB(skb)->map_seq + msk->ack_seq,
-			 MPTCP_SKB_CB(skb)->end_seq, MPTCP_SKB_CB(skb)->end_seq + msk->ack_seq);
-		MPTCP_SKB_CB(skb)->map_seq += msk->ack_seq;
-		MPTCP_SKB_CB(skb)->end_seq += msk->ack_seq;
-	}
-
-	pr_debug("msk=%p ack_seq=%llx", msk, msk->ack_seq);
-	mptcp_data_unlock(sk);
-}