diff --git a/drivers/net/tap.c b/drivers/net/tap.c index 7996ed7cbf18..a4ab4a791fe7 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -1146,14 +1146,84 @@ static const struct file_operations tap_fops = { #endif }; +static int tap_get_user_xdp(struct tap_queue *q, struct xdp_buff *xdp) +{ + struct tun_xdp_hdr *hdr = xdp->data_hard_start; + struct virtio_net_hdr *gso = &hdr->gso; + int buflen = hdr->buflen; + int vnet_hdr_len = 0; + struct tap_dev *tap; + struct sk_buff *skb; + int err, depth; + + if (q->flags & IFF_VNET_HDR) + vnet_hdr_len = READ_ONCE(q->vnet_hdr_sz); + + skb = build_skb(xdp->data_hard_start, buflen); + if (!skb) { + err = -ENOMEM; + goto err; + } + + skb_reserve(skb, xdp->data - xdp->data_hard_start); + skb_put(skb, xdp->data_end - xdp->data); + + skb_set_network_header(skb, ETH_HLEN); + skb_reset_mac_header(skb); + skb->protocol = eth_hdr(skb)->h_proto; + + if (vnet_hdr_len) { + err = virtio_net_hdr_to_skb(skb, gso, tap_is_little_endian(q)); + if (err) + goto err_kfree; + } + + skb_probe_transport_header(skb, ETH_HLEN); + + /* Move network header to the right position for VLAN tagged packets */ + if ((skb->protocol == htons(ETH_P_8021Q) || + skb->protocol == htons(ETH_P_8021AD)) && + __vlan_get_protocol(skb, skb->protocol, &depth) != 0) + skb_set_network_header(skb, depth); + + rcu_read_lock(); + tap = rcu_dereference(q->tap); + if (tap) { + skb->dev = tap->dev; + dev_queue_xmit(skb); + } else { + kfree_skb(skb); + } + rcu_read_unlock(); + + return 0; + +err_kfree: + kfree_skb(skb); +err: + rcu_read_lock(); + tap = rcu_dereference(q->tap); + if (tap && tap->count_tx_dropped) + tap->count_tx_dropped(tap); + rcu_read_unlock(); + return err; +} + static int tap_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) { struct tap_queue *q = container_of(sock, struct tap_queue, sock); struct tun_msg_ctl *ctl = m->msg_control; + struct xdp_buff *xdp; + int i; - if (ctl && ctl->type != TUN_MSG_UBUF) - return -EINVAL; + if (ctl && (ctl->type == TUN_MSG_PTR)) { + for (i = 0; i < ctl->num; i++) { + xdp = &((struct xdp_buff *)ctl->ptr)[i]; + tap_get_user_xdp(q, xdp); + } + return 0; + } return tap_get_user(q, ctl ? ctl->ptr : NULL, &m->msg_iter, m->msg_flags & MSG_DONTWAIT);