Commit 36b2f61a authored by Govindarajulu Varadarajan's avatar Govindarajulu Varadarajan Committed by David S. Miller
Browse files

net: handle 802.1P vlan 0 packets properly 



When stack receives pkt: [802.1P vlan 0][802.1AD vlan 100][IPv4],
vlan_do_receive() returns false if it does not find vlan_dev. Later
__netif_receive_skb_core() fails to find packet type handler for
skb->protocol 801.1AD and drops the packet.

801.1P header with vlan id 0 should be handled as untagged packets.
This patch fixes it by checking if vlan_id is 0 and processes next vlan
header.

Signed-off-by: default avatarGovindarajulu Varadarajan <gvaradar@cisco.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1eb4169c

net/core/dev.c

+29 −1
Original line number Diff line number Diff line
@@ -4923,8 +4923,36 @@ skip_classify: 
	}



	if (unlikely(skb_vlan_tag_present(skb))) {

		if (skb_vlan_tag_get_id(skb))

check_vlan_id:

		if (skb_vlan_tag_get_id(skb)) {

			/* Vlan id is non 0 and vlan_do_receive() above couldn't

			 * find vlan device.

			 */

			skb->pkt_type = PACKET_OTHERHOST;

		} else if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||

			   skb->protocol == cpu_to_be16(ETH_P_8021AD)) {

			/* Outer header is 802.1P with vlan 0, inner header is

			 * 802.1Q or 802.1AD and vlan_do_receive() above could

			 * not find vlan dev for vlan id 0.

			 */

			__vlan_hwaccel_clear_tag(skb);

			skb = skb_vlan_untag(skb);

			if (unlikely(!skb))

				goto out;

			if (vlan_do_receive(&skb))

				/* After stripping off 802.1P header with vlan 0

				 * vlan dev is found for inner header.

				 */

				goto another_round;

			else if (unlikely(!skb))

				goto out;

			else

				/* We have stripped outer 802.1P vlan 0 header.

				 * But could not find vlan dev.

				 * check again for vlan id to set OTHERHOST.

				 */

				goto check_vlan_id;

		}

		/* Note: we might in the future use prio bits

		 * and set skb->priority like in vlan_do_receive()

		 * For the time being, just ignore Priority Code Point

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