RE: [EXT] [PATCH net-next] packet: Account for VLAN_HLEN in csum_start when virtio_net_hdr is enabled

[Suman Ghosh]

> static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff
>*skb,
>-			   size_t *len, int vnet_hdr_sz)
>+			   size_t *len, int vnet_hdr_sz,
>+			   const struct sock *sk)
> {
> 	struct virtio_net_hdr_mrg_rxbuf vnet_hdr = { .num_buffers = 0 };
>+	int vlan_hlen;
>
> 	if (*len < vnet_hdr_sz)
> 		return -EINVAL;
> 	*len -= vnet_hdr_sz;
>
>-	if (virtio_net_hdr_from_skb(skb, (struct virtio_net_hdr
>*)&vnet_hdr, vio_le(), true, 0))
>+	if (sk->sk_type == SOCK_RAW && skb_vlan_tag_present(skb))
>+		vlan_hlen = VLAN_HLEN;
>+	else
>+		vlan_hlen = 0;
[Suman] A minor nit. You can initialize vlan_hdr = 0 and get rid of the else.
>+
>+	if (virtio_net_hdr_from_skb(skb, (struct virtio_net_hdr
>*)&vnet_hdr,
>+				    vio_le(), true, vlan_hlen))
> 		return -EINVAL;
>
> 	return memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_sz); @@ -
>2368,13 +2376,21 @@ static int tpacket_rcv(struct sk_buff *skb, struct
>net_device *dev,
> 		__set_bit(slot_id, po->rx_ring.rx_owner_map);
> 	}
>
>-	if (vnet_hdr_sz &&
>-	    virtio_net_hdr_from_skb(skb, h.raw + macoff -
>-				    sizeof(struct virtio_net_hdr),
>-				    vio_le(), true, 0)) {
>-		if (po->tp_version == TPACKET_V3)
>-			prb_clear_blk_fill_status(&po->rx_ring);
>-		goto drop_n_account;
>+	if (vnet_hdr_sz) {
>+		int vlan_hlen;
>+
>+		if (sk->sk_type == SOCK_RAW && skb_vlan_tag_present(skb))
>+			vlan_hlen = VLAN_HLEN;
>+		else
>+			vlan_hlen = 0;
[Suman] Same as previous comment.
>+
>+		if (virtio_net_hdr_from_skb(skb, h.raw + macoff -
>+					    sizeof(struct virtio_net_hdr),
>+					    vio_le(), true, vlan_hlen)) {
>+			if (po->tp_version == TPACKET_V3)
>+				prb_clear_blk_fill_status(&po->rx_ring);
>+			goto drop_n_account;
>+		}
> 	}
>
> 	if (po->tp_version <= TPACKET_V2) {
>@@ -3464,7 +3480,7 @@ static int packet_recvmsg(struct socket *sock,
>struct msghdr *msg, size_t len,
> 	packet_rcv_try_clear_pressure(pkt_sk(sk));
>
> 	if (vnet_hdr_len) {
>-		err = packet_rcv_vnet(msg, skb, &len, vnet_hdr_len);
>+		err = packet_rcv_vnet(msg, skb, &len, vnet_hdr_len, sk);
> 		if (err)
> 			goto out_free;
> 	}
>--
>2.40.1
>