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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /net/hsr/hsr_forward.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--net/hsr/hsr_forward.c638
1 files changed, 638 insertions, 0 deletions
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
new file mode 100644
index 000000000..80cdc6f6b
--- /dev/null
+++ b/net/hsr/hsr_forward.c
@@ -0,0 +1,638 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2011-2014 Autronica Fire and Security AS
+ *
+ * Author(s):
+ * 2011-2014 Arvid Brodin, arvid.brodin@alten.se
+ *
+ * Frame router for HSR and PRP.
+ */
+
+#include "hsr_forward.h"
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/etherdevice.h>
+#include <linux/if_vlan.h>
+#include "hsr_main.h"
+#include "hsr_framereg.h"
+
+struct hsr_node;
+
+/* The uses I can see for these HSR supervision frames are:
+ * 1) Use the frames that are sent after node initialization ("HSR_TLV.Type =
+ * 22") to reset any sequence_nr counters belonging to that node. Useful if
+ * the other node's counter has been reset for some reason.
+ * --
+ * Or not - resetting the counter and bridging the frame would create a
+ * loop, unfortunately.
+ *
+ * 2) Use the LifeCheck frames to detect ring breaks. I.e. if no LifeCheck
+ * frame is received from a particular node, we know something is wrong.
+ * We just register these (as with normal frames) and throw them away.
+ *
+ * 3) Allow different MAC addresses for the two slave interfaces, using the
+ * MacAddressA field.
+ */
+static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb)
+{
+ struct ethhdr *eth_hdr;
+ struct hsr_sup_tag *hsr_sup_tag;
+ struct hsrv1_ethhdr_sp *hsr_V1_hdr;
+ struct hsr_sup_tlv *hsr_sup_tlv;
+ u16 total_length = 0;
+
+ WARN_ON_ONCE(!skb_mac_header_was_set(skb));
+ eth_hdr = (struct ethhdr *)skb_mac_header(skb);
+
+ /* Correct addr? */
+ if (!ether_addr_equal(eth_hdr->h_dest,
+ hsr->sup_multicast_addr))
+ return false;
+
+ /* Correct ether type?. */
+ if (!(eth_hdr->h_proto == htons(ETH_P_PRP) ||
+ eth_hdr->h_proto == htons(ETH_P_HSR)))
+ return false;
+
+ /* Get the supervision header from correct location. */
+ if (eth_hdr->h_proto == htons(ETH_P_HSR)) { /* Okay HSRv1. */
+ total_length = sizeof(struct hsrv1_ethhdr_sp);
+ if (!pskb_may_pull(skb, total_length))
+ return false;
+
+ hsr_V1_hdr = (struct hsrv1_ethhdr_sp *)skb_mac_header(skb);
+ if (hsr_V1_hdr->hsr.encap_proto != htons(ETH_P_PRP))
+ return false;
+
+ hsr_sup_tag = &hsr_V1_hdr->hsr_sup;
+ } else {
+ total_length = sizeof(struct hsrv0_ethhdr_sp);
+ if (!pskb_may_pull(skb, total_length))
+ return false;
+
+ hsr_sup_tag =
+ &((struct hsrv0_ethhdr_sp *)skb_mac_header(skb))->hsr_sup;
+ }
+
+ if (hsr_sup_tag->tlv.HSR_TLV_type != HSR_TLV_ANNOUNCE &&
+ hsr_sup_tag->tlv.HSR_TLV_type != HSR_TLV_LIFE_CHECK &&
+ hsr_sup_tag->tlv.HSR_TLV_type != PRP_TLV_LIFE_CHECK_DD &&
+ hsr_sup_tag->tlv.HSR_TLV_type != PRP_TLV_LIFE_CHECK_DA)
+ return false;
+ if (hsr_sup_tag->tlv.HSR_TLV_length != 12 &&
+ hsr_sup_tag->tlv.HSR_TLV_length != sizeof(struct hsr_sup_payload))
+ return false;
+
+ /* Get next tlv */
+ total_length += sizeof(struct hsr_sup_tlv) + hsr_sup_tag->tlv.HSR_TLV_length;
+ if (!pskb_may_pull(skb, total_length))
+ return false;
+ skb_pull(skb, total_length);
+ hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
+ skb_push(skb, total_length);
+
+ /* if this is a redbox supervision frame we need to verify
+ * that more data is available
+ */
+ if (hsr_sup_tlv->HSR_TLV_type == PRP_TLV_REDBOX_MAC) {
+ /* tlv length must be a length of a mac address */
+ if (hsr_sup_tlv->HSR_TLV_length != sizeof(struct hsr_sup_payload))
+ return false;
+
+ /* make sure another tlv follows */
+ total_length += sizeof(struct hsr_sup_tlv) + hsr_sup_tlv->HSR_TLV_length;
+ if (!pskb_may_pull(skb, total_length))
+ return false;
+
+ /* get next tlv */
+ skb_pull(skb, total_length);
+ hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
+ skb_push(skb, total_length);
+ }
+
+ /* end of tlvs must follow at the end */
+ if (hsr_sup_tlv->HSR_TLV_type == HSR_TLV_EOT &&
+ hsr_sup_tlv->HSR_TLV_length != 0)
+ return false;
+
+ return true;
+}
+
+static struct sk_buff *create_stripped_skb_hsr(struct sk_buff *skb_in,
+ struct hsr_frame_info *frame)
+{
+ struct sk_buff *skb;
+ int copylen;
+ unsigned char *dst, *src;
+
+ skb_pull(skb_in, HSR_HLEN);
+ skb = __pskb_copy(skb_in, skb_headroom(skb_in) - HSR_HLEN, GFP_ATOMIC);
+ skb_push(skb_in, HSR_HLEN);
+ if (!skb)
+ return NULL;
+
+ skb_reset_mac_header(skb);
+
+ if (skb->ip_summed == CHECKSUM_PARTIAL)
+ skb->csum_start -= HSR_HLEN;
+
+ copylen = 2 * ETH_ALEN;
+ if (frame->is_vlan)
+ copylen += VLAN_HLEN;
+ src = skb_mac_header(skb_in);
+ dst = skb_mac_header(skb);
+ memcpy(dst, src, copylen);
+
+ skb->protocol = eth_hdr(skb)->h_proto;
+ return skb;
+}
+
+struct sk_buff *hsr_get_untagged_frame(struct hsr_frame_info *frame,
+ struct hsr_port *port)
+{
+ if (!frame->skb_std) {
+ if (frame->skb_hsr)
+ frame->skb_std =
+ create_stripped_skb_hsr(frame->skb_hsr, frame);
+ else
+ netdev_warn_once(port->dev,
+ "Unexpected frame received in hsr_get_untagged_frame()\n");
+
+ if (!frame->skb_std)
+ return NULL;
+ }
+
+ return skb_clone(frame->skb_std, GFP_ATOMIC);
+}
+
+struct sk_buff *prp_get_untagged_frame(struct hsr_frame_info *frame,
+ struct hsr_port *port)
+{
+ if (!frame->skb_std) {
+ if (frame->skb_prp) {
+ /* trim the skb by len - HSR_HLEN to exclude RCT */
+ skb_trim(frame->skb_prp,
+ frame->skb_prp->len - HSR_HLEN);
+ frame->skb_std =
+ __pskb_copy(frame->skb_prp,
+ skb_headroom(frame->skb_prp),
+ GFP_ATOMIC);
+ } else {
+ /* Unexpected */
+ WARN_ONCE(1, "%s:%d: Unexpected frame received (port_src %s)\n",
+ __FILE__, __LINE__, port->dev->name);
+ return NULL;
+ }
+ }
+
+ return skb_clone(frame->skb_std, GFP_ATOMIC);
+}
+
+static void prp_set_lan_id(struct prp_rct *trailer,
+ struct hsr_port *port)
+{
+ int lane_id;
+
+ if (port->type == HSR_PT_SLAVE_A)
+ lane_id = 0;
+ else
+ lane_id = 1;
+
+ /* Add net_id in the upper 3 bits of lane_id */
+ lane_id |= port->hsr->net_id;
+ set_prp_lan_id(trailer, lane_id);
+}
+
+/* Tailroom for PRP rct should have been created before calling this */
+static struct sk_buff *prp_fill_rct(struct sk_buff *skb,
+ struct hsr_frame_info *frame,
+ struct hsr_port *port)
+{
+ struct prp_rct *trailer;
+ int min_size = ETH_ZLEN;
+ int lsdu_size;
+
+ if (!skb)
+ return skb;
+
+ if (frame->is_vlan)
+ min_size = VLAN_ETH_ZLEN;
+
+ if (skb_put_padto(skb, min_size))
+ return NULL;
+
+ trailer = (struct prp_rct *)skb_put(skb, HSR_HLEN);
+ lsdu_size = skb->len - 14;
+ if (frame->is_vlan)
+ lsdu_size -= 4;
+ prp_set_lan_id(trailer, port);
+ set_prp_LSDU_size(trailer, lsdu_size);
+ trailer->sequence_nr = htons(frame->sequence_nr);
+ trailer->PRP_suffix = htons(ETH_P_PRP);
+ skb->protocol = eth_hdr(skb)->h_proto;
+
+ return skb;
+}
+
+static void hsr_set_path_id(struct hsr_ethhdr *hsr_ethhdr,
+ struct hsr_port *port)
+{
+ int path_id;
+
+ if (port->type == HSR_PT_SLAVE_A)
+ path_id = 0;
+ else
+ path_id = 1;
+
+ set_hsr_tag_path(&hsr_ethhdr->hsr_tag, path_id);
+}
+
+static struct sk_buff *hsr_fill_tag(struct sk_buff *skb,
+ struct hsr_frame_info *frame,
+ struct hsr_port *port, u8 proto_version)
+{
+ struct hsr_ethhdr *hsr_ethhdr;
+ int lsdu_size;
+
+ /* pad to minimum packet size which is 60 + 6 (HSR tag) */
+ if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN))
+ return NULL;
+
+ lsdu_size = skb->len - 14;
+ if (frame->is_vlan)
+ lsdu_size -= 4;
+
+ hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb);
+
+ hsr_set_path_id(hsr_ethhdr, port);
+ set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size);
+ hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr);
+ hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
+ hsr_ethhdr->ethhdr.h_proto = htons(proto_version ?
+ ETH_P_HSR : ETH_P_PRP);
+ skb->protocol = hsr_ethhdr->ethhdr.h_proto;
+
+ return skb;
+}
+
+/* If the original frame was an HSR tagged frame, just clone it to be sent
+ * unchanged. Otherwise, create a private frame especially tagged for 'port'.
+ */
+struct sk_buff *hsr_create_tagged_frame(struct hsr_frame_info *frame,
+ struct hsr_port *port)
+{
+ unsigned char *dst, *src;
+ struct sk_buff *skb;
+ int movelen;
+
+ if (frame->skb_hsr) {
+ struct hsr_ethhdr *hsr_ethhdr =
+ (struct hsr_ethhdr *)skb_mac_header(frame->skb_hsr);
+
+ /* set the lane id properly */
+ hsr_set_path_id(hsr_ethhdr, port);
+ return skb_clone(frame->skb_hsr, GFP_ATOMIC);
+ } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
+ return skb_clone(frame->skb_std, GFP_ATOMIC);
+ }
+
+ /* Create the new skb with enough headroom to fit the HSR tag */
+ skb = __pskb_copy(frame->skb_std,
+ skb_headroom(frame->skb_std) + HSR_HLEN, GFP_ATOMIC);
+ if (!skb)
+ return NULL;
+ skb_reset_mac_header(skb);
+
+ if (skb->ip_summed == CHECKSUM_PARTIAL)
+ skb->csum_start += HSR_HLEN;
+
+ movelen = ETH_HLEN;
+ if (frame->is_vlan)
+ movelen += VLAN_HLEN;
+
+ src = skb_mac_header(skb);
+ dst = skb_push(skb, HSR_HLEN);
+ memmove(dst, src, movelen);
+ skb_reset_mac_header(skb);
+
+ /* skb_put_padto free skb on error and hsr_fill_tag returns NULL in
+ * that case
+ */
+ return hsr_fill_tag(skb, frame, port, port->hsr->prot_version);
+}
+
+struct sk_buff *prp_create_tagged_frame(struct hsr_frame_info *frame,
+ struct hsr_port *port)
+{
+ struct sk_buff *skb;
+
+ if (frame->skb_prp) {
+ struct prp_rct *trailer = skb_get_PRP_rct(frame->skb_prp);
+
+ if (trailer) {
+ prp_set_lan_id(trailer, port);
+ } else {
+ WARN_ONCE(!trailer, "errored PRP skb");
+ return NULL;
+ }
+ return skb_clone(frame->skb_prp, GFP_ATOMIC);
+ } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
+ return skb_clone(frame->skb_std, GFP_ATOMIC);
+ }
+
+ skb = skb_copy_expand(frame->skb_std, 0,
+ skb_tailroom(frame->skb_std) + HSR_HLEN,
+ GFP_ATOMIC);
+ return prp_fill_rct(skb, frame, port);
+}
+
+static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,
+ struct hsr_node *node_src)
+{
+ bool was_multicast_frame;
+ int res, recv_len;
+
+ was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
+ hsr_addr_subst_source(node_src, skb);
+ skb_pull(skb, ETH_HLEN);
+ recv_len = skb->len;
+ res = netif_rx(skb);
+ if (res == NET_RX_DROP) {
+ dev->stats.rx_dropped++;
+ } else {
+ dev->stats.rx_packets++;
+ dev->stats.rx_bytes += recv_len;
+ if (was_multicast_frame)
+ dev->stats.multicast++;
+ }
+}
+
+static int hsr_xmit(struct sk_buff *skb, struct hsr_port *port,
+ struct hsr_frame_info *frame)
+{
+ if (frame->port_rcv->type == HSR_PT_MASTER) {
+ hsr_addr_subst_dest(frame->node_src, skb, port);
+
+ /* Address substitution (IEC62439-3 pp 26, 50): replace mac
+ * address of outgoing frame with that of the outgoing slave's.
+ */
+ ether_addr_copy(eth_hdr(skb)->h_source, port->dev->dev_addr);
+ }
+ return dev_queue_xmit(skb);
+}
+
+bool prp_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
+{
+ return ((frame->port_rcv->type == HSR_PT_SLAVE_A &&
+ port->type == HSR_PT_SLAVE_B) ||
+ (frame->port_rcv->type == HSR_PT_SLAVE_B &&
+ port->type == HSR_PT_SLAVE_A));
+}
+
+bool hsr_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
+{
+ if (port->dev->features & NETIF_F_HW_HSR_FWD)
+ return prp_drop_frame(frame, port);
+
+ return false;
+}
+
+/* Forward the frame through all devices except:
+ * - Back through the receiving device
+ * - If it's a HSR frame: through a device where it has passed before
+ * - if it's a PRP frame: through another PRP slave device (no bridge)
+ * - To the local HSR master only if the frame is directly addressed to it, or
+ * a non-supervision multicast or broadcast frame.
+ *
+ * HSR slave devices should insert a HSR tag into the frame, or forward the
+ * frame unchanged if it's already tagged. Interlink devices should strip HSR
+ * tags if they're of the non-HSR type (but only after duplicate discard). The
+ * master device always strips HSR tags.
+ */
+static void hsr_forward_do(struct hsr_frame_info *frame)
+{
+ struct hsr_port *port;
+ struct sk_buff *skb;
+ bool sent = false;
+
+ hsr_for_each_port(frame->port_rcv->hsr, port) {
+ struct hsr_priv *hsr = port->hsr;
+ /* Don't send frame back the way it came */
+ if (port == frame->port_rcv)
+ continue;
+
+ /* Don't deliver locally unless we should */
+ if (port->type == HSR_PT_MASTER && !frame->is_local_dest)
+ continue;
+
+ /* Deliver frames directly addressed to us to master only */
+ if (port->type != HSR_PT_MASTER && frame->is_local_exclusive)
+ continue;
+
+ /* If hardware duplicate generation is enabled, only send out
+ * one port.
+ */
+ if ((port->dev->features & NETIF_F_HW_HSR_DUP) && sent)
+ continue;
+
+ /* Don't send frame over port where it has been sent before.
+ * Also fro SAN, this shouldn't be done.
+ */
+ if (!frame->is_from_san &&
+ hsr_register_frame_out(port, frame->node_src,
+ frame->sequence_nr))
+ continue;
+
+ if (frame->is_supervision && port->type == HSR_PT_MASTER) {
+ hsr_handle_sup_frame(frame);
+ continue;
+ }
+
+ /* Check if frame is to be dropped. Eg. for PRP no forward
+ * between ports.
+ */
+ if (hsr->proto_ops->drop_frame &&
+ hsr->proto_ops->drop_frame(frame, port))
+ continue;
+
+ if (port->type != HSR_PT_MASTER)
+ skb = hsr->proto_ops->create_tagged_frame(frame, port);
+ else
+ skb = hsr->proto_ops->get_untagged_frame(frame, port);
+
+ if (!skb) {
+ frame->port_rcv->dev->stats.rx_dropped++;
+ continue;
+ }
+
+ skb->dev = port->dev;
+ if (port->type == HSR_PT_MASTER) {
+ hsr_deliver_master(skb, port->dev, frame->node_src);
+ } else {
+ if (!hsr_xmit(skb, port, frame))
+ sent = true;
+ }
+ }
+}
+
+static void check_local_dest(struct hsr_priv *hsr, struct sk_buff *skb,
+ struct hsr_frame_info *frame)
+{
+ if (hsr_addr_is_self(hsr, eth_hdr(skb)->h_dest)) {
+ frame->is_local_exclusive = true;
+ skb->pkt_type = PACKET_HOST;
+ } else {
+ frame->is_local_exclusive = false;
+ }
+
+ if (skb->pkt_type == PACKET_HOST ||
+ skb->pkt_type == PACKET_MULTICAST ||
+ skb->pkt_type == PACKET_BROADCAST) {
+ frame->is_local_dest = true;
+ } else {
+ frame->is_local_dest = false;
+ }
+}
+
+static void handle_std_frame(struct sk_buff *skb,
+ struct hsr_frame_info *frame)
+{
+ struct hsr_port *port = frame->port_rcv;
+ struct hsr_priv *hsr = port->hsr;
+
+ frame->skb_hsr = NULL;
+ frame->skb_prp = NULL;
+ frame->skb_std = skb;
+
+ if (port->type != HSR_PT_MASTER) {
+ frame->is_from_san = true;
+ } else {
+ /* Sequence nr for the master node */
+ lockdep_assert_held(&hsr->seqnr_lock);
+ frame->sequence_nr = hsr->sequence_nr;
+ hsr->sequence_nr++;
+ }
+}
+
+int hsr_fill_frame_info(__be16 proto, struct sk_buff *skb,
+ struct hsr_frame_info *frame)
+{
+ struct hsr_port *port = frame->port_rcv;
+ struct hsr_priv *hsr = port->hsr;
+
+ /* HSRv0 supervisory frames double as a tag so treat them as tagged. */
+ if ((!hsr->prot_version && proto == htons(ETH_P_PRP)) ||
+ proto == htons(ETH_P_HSR)) {
+ /* Check if skb contains hsr_ethhdr */
+ if (skb->mac_len < sizeof(struct hsr_ethhdr))
+ return -EINVAL;
+
+ /* HSR tagged frame :- Data or Supervision */
+ frame->skb_std = NULL;
+ frame->skb_prp = NULL;
+ frame->skb_hsr = skb;
+ frame->sequence_nr = hsr_get_skb_sequence_nr(skb);
+ return 0;
+ }
+
+ /* Standard frame or PRP from master port */
+ handle_std_frame(skb, frame);
+
+ return 0;
+}
+
+int prp_fill_frame_info(__be16 proto, struct sk_buff *skb,
+ struct hsr_frame_info *frame)
+{
+ /* Supervision frame */
+ struct prp_rct *rct = skb_get_PRP_rct(skb);
+
+ if (rct &&
+ prp_check_lsdu_size(skb, rct, frame->is_supervision)) {
+ frame->skb_hsr = NULL;
+ frame->skb_std = NULL;
+ frame->skb_prp = skb;
+ frame->sequence_nr = prp_get_skb_sequence_nr(rct);
+ return 0;
+ }
+ handle_std_frame(skb, frame);
+
+ return 0;
+}
+
+static int fill_frame_info(struct hsr_frame_info *frame,
+ struct sk_buff *skb, struct hsr_port *port)
+{
+ struct hsr_priv *hsr = port->hsr;
+ struct hsr_vlan_ethhdr *vlan_hdr;
+ struct ethhdr *ethhdr;
+ __be16 proto;
+ int ret;
+
+ /* Check if skb contains ethhdr */
+ if (skb->mac_len < sizeof(struct ethhdr))
+ return -EINVAL;
+
+ memset(frame, 0, sizeof(*frame));
+ frame->is_supervision = is_supervision_frame(port->hsr, skb);
+ frame->node_src = hsr_get_node(port, &hsr->node_db, skb,
+ frame->is_supervision,
+ port->type);
+ if (!frame->node_src)
+ return -1; /* Unknown node and !is_supervision, or no mem */
+
+ ethhdr = (struct ethhdr *)skb_mac_header(skb);
+ frame->is_vlan = false;
+ proto = ethhdr->h_proto;
+
+ if (proto == htons(ETH_P_8021Q))
+ frame->is_vlan = true;
+
+ if (frame->is_vlan) {
+ vlan_hdr = (struct hsr_vlan_ethhdr *)ethhdr;
+ proto = vlan_hdr->vlanhdr.h_vlan_encapsulated_proto;
+ /* FIXME: */
+ netdev_warn_once(skb->dev, "VLAN not yet supported");
+ return -EINVAL;
+ }
+
+ frame->is_from_san = false;
+ frame->port_rcv = port;
+ ret = hsr->proto_ops->fill_frame_info(proto, skb, frame);
+ if (ret)
+ return ret;
+
+ check_local_dest(port->hsr, skb, frame);
+
+ return 0;
+}
+
+/* Must be called holding rcu read lock (because of the port parameter) */
+void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port)
+{
+ struct hsr_frame_info frame;
+
+ rcu_read_lock();
+ if (fill_frame_info(&frame, skb, port) < 0)
+ goto out_drop;
+
+ hsr_register_frame_in(frame.node_src, port, frame.sequence_nr);
+ hsr_forward_do(&frame);
+ rcu_read_unlock();
+ /* Gets called for ingress frames as well as egress from master port.
+ * So check and increment stats for master port only here.
+ */
+ if (port->type == HSR_PT_MASTER) {
+ port->dev->stats.tx_packets++;
+ port->dev->stats.tx_bytes += skb->len;
+ }
+
+ kfree_skb(frame.skb_hsr);
+ kfree_skb(frame.skb_prp);
+ kfree_skb(frame.skb_std);
+ return;
+
+out_drop:
+ rcu_read_unlock();
+ port->dev->stats.tx_dropped++;
+ kfree_skb(skb);
+}