--- v10
+++ v3
@@ -1,43 +1,153 @@
-This function is static and 'hdr' arg was always NULL.
+This modifies current receive logic for SEQPACKET support:
+1) Inserts 'SEQ_BEGIN' packet to socket's rx queue.
+2) Inserts 'RW' packet to socket's rx queue, but without merging with
+   buffer of last packet in queue.
+3) Performs check for packet and socket types on receive(if mismatch,
+   then reset connection).
 
 Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
-Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
 ---
- net/vmw_vsock/virtio_transport_common.c | 7 +++----
- 1 file changed, 3 insertions(+), 4 deletions(-)
+ net/vmw_vsock/virtio_transport_common.c | 79 ++++++++++++++++++-------
+ 1 file changed, 58 insertions(+), 21 deletions(-)
 
 diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
-index 6503a8370130..ad0d34d41444 100644
+index dcce35d7b462..90f9feef9d8f 100644
 --- a/net/vmw_vsock/virtio_transport_common.c
 +++ b/net/vmw_vsock/virtio_transport_common.c
-@@ -271,8 +271,7 @@ void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit)
+@@ -397,6 +397,14 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
+ 	return err;
  }
- EXPORT_SYMBOL_GPL(virtio_transport_put_credit);
  
--static int virtio_transport_send_credit_update(struct vsock_sock *vsk,
--					       struct virtio_vsock_hdr *hdr)
-+static int virtio_transport_send_credit_update(struct vsock_sock *vsk)
++static u16 virtio_transport_get_type(struct sock *sk)
++{
++	if (sk->sk_type == SOCK_STREAM)
++		return VIRTIO_VSOCK_TYPE_STREAM;
++	else
++		return VIRTIO_VSOCK_TYPE_SEQPACKET;
++}
++
+ static inline void virtio_transport_del_n_free_pkt(struct virtio_vsock_pkt *pkt)
  {
- 	struct virtio_vsock_pkt_info info = {
- 		.op = VIRTIO_VSOCK_OP_CREDIT_UPDATE,
-@@ -384,7 +383,7 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
- 	 * with different values.
- 	 */
- 	if (free_space < VIRTIO_VSOCK_MAX_PKT_BUF_SIZE)
--		virtio_transport_send_credit_update(vsk, NULL);
-+		virtio_transport_send_credit_update(vsk);
+ 	list_del(&pkt->list);
+@@ -1050,39 +1058,49 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk,
+ 			      struct virtio_vsock_pkt *pkt)
+ {
+ 	struct virtio_vsock_sock *vvs = vsk->trans;
+-	bool can_enqueue, free_pkt = false;
++	bool free_pkt = false;
  
- 	return total;
+ 	pkt->len = le32_to_cpu(pkt->hdr.len);
+ 	pkt->off = 0;
  
-@@ -493,7 +492,7 @@ void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val)
+ 	spin_lock_bh(&vvs->rx_lock);
  
- 	vvs->buf_alloc = *val;
+-	can_enqueue = virtio_transport_inc_rx_pkt(vvs, pkt);
+-	if (!can_enqueue) {
++	if (!virtio_transport_inc_rx_pkt(vvs, pkt)) {
+ 		free_pkt = true;
+ 		goto out;
+ 	}
  
--	virtio_transport_send_credit_update(vsk, NULL);
-+	virtio_transport_send_credit_update(vsk);
+-	/* Try to copy small packets into the buffer of last packet queued,
+-	 * to avoid wasting memory queueing the entire buffer with a small
+-	 * payload.
+-	 */
+-	if (pkt->len <= GOOD_COPY_LEN && !list_empty(&vvs->rx_queue)) {
+-		struct virtio_vsock_pkt *last_pkt;
++	switch (le16_to_cpu(pkt->hdr.type)) {
++	case VIRTIO_VSOCK_TYPE_STREAM: {
++		/* Try to copy small packets into the buffer of last packet queued,
++		 * to avoid wasting memory queueing the entire buffer with a small
++		 * payload.
++		 */
++		if (pkt->len <= GOOD_COPY_LEN && !list_empty(&vvs->rx_queue)) {
++			struct virtio_vsock_pkt *last_pkt;
+ 
+-		last_pkt = list_last_entry(&vvs->rx_queue,
+-					   struct virtio_vsock_pkt, list);
++			last_pkt = list_last_entry(&vvs->rx_queue,
++						   struct virtio_vsock_pkt, list);
+ 
+-		/* If there is space in the last packet queued, we copy the
+-		 * new packet in its buffer.
+-		 */
+-		if (pkt->len <= last_pkt->buf_len - last_pkt->len) {
+-			memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
+-			       pkt->len);
+-			last_pkt->len += pkt->len;
+-			free_pkt = true;
+-			goto out;
++			/* If there is space in the last packet queued, we copy the
++			 * new packet in its buffer.
++			 */
++			if (pkt->len <= last_pkt->buf_len - last_pkt->len) {
++				memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
++				       pkt->len);
++				last_pkt->len += pkt->len;
++				free_pkt = true;
++				goto out;
++			}
+ 		}
++
++		break;
++	}
++	case VIRTIO_VSOCK_TYPE_SEQPACKET: {
++		break;
++	}
++	default:
++		goto out;
+ 	}
+ 
+ 	list_add_tail(&pkt->list, &vvs->rx_queue);
+@@ -1101,6 +1119,14 @@ virtio_transport_recv_connected(struct sock *sk,
+ 	int err = 0;
+ 
+ 	switch (le16_to_cpu(pkt->hdr.op)) {
++	case VIRTIO_VSOCK_OP_SEQ_BEGIN: {
++		struct virtio_vsock_sock *vvs = vsk->trans;
++
++		spin_lock_bh(&vvs->rx_lock);
++		list_add_tail(&pkt->list, &vvs->rx_queue);
++		spin_unlock_bh(&vvs->rx_lock);
++		return err;
++	}
+ 	case VIRTIO_VSOCK_OP_RW:
+ 		virtio_transport_recv_enqueue(vsk, pkt);
+ 		sk->sk_data_ready(sk);
+@@ -1247,6 +1273,12 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt,
+ 	return 0;
  }
- EXPORT_SYMBOL_GPL(virtio_transport_notify_buffer_size);
  
++static bool virtio_transport_valid_type(u16 type)
++{
++	return (type == VIRTIO_VSOCK_TYPE_STREAM) ||
++	       (type == VIRTIO_VSOCK_TYPE_SEQPACKET);
++}
++
+ /* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex
+  * lock.
+  */
+@@ -1272,7 +1304,7 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
+ 					le32_to_cpu(pkt->hdr.buf_alloc),
+ 					le32_to_cpu(pkt->hdr.fwd_cnt));
+ 
+-	if (le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_STREAM) {
++	if (!virtio_transport_valid_type(le16_to_cpu(pkt->hdr.type))) {
+ 		(void)virtio_transport_reset_no_sock(t, pkt);
+ 		goto free_pkt;
+ 	}
+@@ -1289,6 +1321,11 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
+ 		}
+ 	}
+ 
++	if (virtio_transport_get_type(sk) != le16_to_cpu(pkt->hdr.type)) {
++		(void)virtio_transport_reset_no_sock(t, pkt);
++		goto free_pkt;
++	}
++
+ 	vsk = vsock_sk(sk);
+ 
+ 	space_available = virtio_transport_space_update(sk, pkt);
 -- 
 2.25.1