vlan_dev: VLAN 0 should be treated as "no vlan tag" (802.1p packet)

- Without the 8021q module loaded in the kernel, all 802.1p packets 
(VLAN 0 but QoS tagging) are silently discarded (as expected, as 
the protocol is not loaded).
 
- Without this patch in 8021q module, these packets are forwarded to 
the module, but they are discarded also if VLAN 0 is not configured,
which should not be the default behaviour, as VLAN 0 is not really
a VLANed packet but a 802.1p packet. Defining VLAN 0 makes it almost
impossible to communicate with mixed 802.1p and non 802.1p devices on
the same network due to arp table issues.

- Changed logic to skip vlan specific code in vlan_skb_recv if VLAN 
is 0 and we have not defined a VLAN with ID 0, but we accept the 
packet with the encapsulated proto and pass it later to netif_rx.

- In the vlan device event handler, added some logic to add VLAN 0 
to HW filter in devices that support it (this prevented any traffic
in VLAN 0 to reach the stack in e1000e with HW filter under 2.6.35,
and probably also with other HW filtered cards, so we fix it here).

- In the vlan unregister logic, prevent the elimination of VLAN 0 
in devices with HW filter.

- The default behaviour is to ignore the VLAN 0 tagging and accept
the packet as if it was not tagged, but we can still define a 
VLAN 0 if desired (so it is backwards compatible).

Signed-off-by: Pedro Garcia <pedro.netdev@dondevamos.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Pedro Garcia 2010-07-18 15:38:44 -07:00 committed by David S. Miller
parent 01893c82b4
commit ad1afb0039
3 changed files with 87 additions and 50 deletions

View File

@ -155,9 +155,10 @@ void unregister_vlan_dev(struct net_device *dev, struct list_head *head)
BUG_ON(!grp);
/* Take it out of our own structures, but be sure to interlock with
* HW accelerating devices or SW vlan input packet processing.
* HW accelerating devices or SW vlan input packet processing if
* VLAN is not 0 (leave it there for 802.1p).
*/
if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
if (vlan_id && (real_dev->features & NETIF_F_HW_VLAN_FILTER))
ops->ndo_vlan_rx_kill_vid(real_dev, vlan_id);
grp->nr_vlans--;
@ -419,6 +420,14 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event,
if (is_vlan_dev(dev))
__vlan_device_event(dev, event);
if ((event == NETDEV_UP) &&
(dev->features & NETIF_F_HW_VLAN_FILTER) &&
dev->netdev_ops->ndo_vlan_rx_add_vid) {
pr_info("8021q: adding VLAN 0 to HW filter on device %s\n",
dev->name);
dev->netdev_ops->ndo_vlan_rx_add_vid(dev, 0);
}
grp = __vlan_find_group(dev);
if (!grp)
goto out;

View File

@ -8,6 +8,9 @@
int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
u16 vlan_tci, int polling)
{
struct net_device *vlan_dev;
u16 vlan_id;
if (netpoll_rx(skb))
return NET_RX_DROP;
@ -16,9 +19,12 @@ int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
skb->skb_iif = skb->dev->ifindex;
__vlan_hwaccel_put_tag(skb, vlan_tci);
skb->dev = vlan_group_get_device(grp, vlan_tci & VLAN_VID_MASK);
vlan_id = vlan_tci & VLAN_VID_MASK;
vlan_dev = vlan_group_get_device(grp, vlan_id);
if (!skb->dev)
if (vlan_dev)
skb->dev = vlan_dev;
else if (vlan_id)
goto drop;
return (polling ? netif_receive_skb(skb) : netif_rx(skb));
@ -83,15 +89,20 @@ vlan_gro_common(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb)
{
struct sk_buff *p;
struct net_device *vlan_dev;
u16 vlan_id;
if (skb_bond_should_drop(skb, ACCESS_ONCE(skb->dev->master)))
skb->deliver_no_wcard = 1;
skb->skb_iif = skb->dev->ifindex;
__vlan_hwaccel_put_tag(skb, vlan_tci);
skb->dev = vlan_group_get_device(grp, vlan_tci & VLAN_VID_MASK);
vlan_id = vlan_tci & VLAN_VID_MASK;
vlan_dev = vlan_group_get_device(grp, vlan_id);
if (!skb->dev)
if (vlan_dev)
skb->dev = vlan_dev;
else if (vlan_id)
goto drop;
for (p = napi->gro_list; p; p = p->next) {

View File

@ -142,6 +142,7 @@ int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
{
struct vlan_hdr *vhdr;
struct vlan_rx_stats *rx_stats;
struct net_device *vlan_dev;
u16 vlan_id;
u16 vlan_tci;
@ -157,55 +158,71 @@ int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
vlan_id = vlan_tci & VLAN_VID_MASK;
rcu_read_lock();
skb->dev = __find_vlan_dev(dev, vlan_id);
if (!skb->dev) {
pr_debug("%s: ERROR: No net_device for VID: %u on dev: %s\n",
__func__, vlan_id, dev->name);
goto err_unlock;
}
vlan_dev = __find_vlan_dev(dev, vlan_id);
rx_stats = per_cpu_ptr(vlan_dev_info(skb->dev)->vlan_rx_stats,
smp_processor_id());
u64_stats_update_begin(&rx_stats->syncp);
rx_stats->rx_packets++;
rx_stats->rx_bytes += skb->len;
/* If the VLAN device is defined, we use it.
* If not, and the VID is 0, it is a 802.1p packet (not
* really a VLAN), so we will just netif_rx it later to the
* original interface, but with the skb->proto set to the
* wrapped proto: we do nothing here.
*/
if (!vlan_dev) {
if (vlan_id) {
pr_debug("%s: ERROR: No net_device for VID: %u on dev: %s\n",
__func__, vlan_id, dev->name);
goto err_unlock;
}
rx_stats = NULL;
} else {
skb->dev = vlan_dev;
rx_stats = per_cpu_ptr(vlan_dev_info(skb->dev)->vlan_rx_stats,
smp_processor_id());
u64_stats_update_begin(&rx_stats->syncp);
rx_stats->rx_packets++;
rx_stats->rx_bytes += skb->len;
skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tci);
pr_debug("%s: priority: %u for TCI: %hu\n",
__func__, skb->priority, vlan_tci);
switch (skb->pkt_type) {
case PACKET_BROADCAST:
/* Yeah, stats collect these together.. */
/* stats->broadcast ++; // no such counter :-( */
break;
case PACKET_MULTICAST:
rx_stats->rx_multicast++;
break;
case PACKET_OTHERHOST:
/* Our lower layer thinks this is not local, let's make
* sure.
* This allows the VLAN to have a different MAC than the
* underlying device, and still route correctly.
*/
if (!compare_ether_addr(eth_hdr(skb)->h_dest,
skb->dev->dev_addr))
skb->pkt_type = PACKET_HOST;
break;
default:
break;
}
u64_stats_update_end(&rx_stats->syncp);
}
skb_pull_rcsum(skb, VLAN_HLEN);
skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tci);
pr_debug("%s: priority: %u for TCI: %hu\n",
__func__, skb->priority, vlan_tci);
switch (skb->pkt_type) {
case PACKET_BROADCAST: /* Yeah, stats collect these together.. */
/* stats->broadcast ++; // no such counter :-( */
break;
case PACKET_MULTICAST:
rx_stats->rx_multicast++;
break;
case PACKET_OTHERHOST:
/* Our lower layer thinks this is not local, let's make sure.
* This allows the VLAN to have a different MAC than the
* underlying device, and still route correctly.
*/
if (!compare_ether_addr(eth_hdr(skb)->h_dest,
skb->dev->dev_addr))
skb->pkt_type = PACKET_HOST;
break;
default:
break;
}
u64_stats_update_end(&rx_stats->syncp);
vlan_set_encap_proto(skb, vhdr);
skb = vlan_check_reorder_header(skb);
if (!skb) {
rx_stats->rx_errors++;
goto err_unlock;
if (vlan_dev) {
skb = vlan_check_reorder_header(skb);
if (!skb) {
rx_stats->rx_errors++;
goto err_unlock;
}
}
netif_rx(skb);