Commit 12a2856b authored Mar 14, 2011 by Daniel Lezcano Committed by David S. Miller Mar 14, 2011

macvlan : fix checksums error when we are in bridge mode



When the lower device has offloading capabilities, the packets checksums
are not computed. That leads to have any macvlan port in bridge mode to
not work because the packets are dropped due to a bad checksum.

If the macvlan is in bridge mode, the packet is forwarded to another
macvlan port and reach the network stack where it looks for a checksum
but this one was not computed due to the offloading of the lower device.
In this case, we have to set the packet with CHECKSUM_UNNECESSARY
when it is forwarded to a bridged port and restore the previous value of
ip_summed when the packet goes to the lowerdev.

Signed-off-by: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Andrian Nord <nightnord@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent b5ccd073

drivers/net/macvlan.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -219,9 +219,11 @@ static int macvlan_queue_xmit(struct sk_buff skb, struct net_device dev)
		const struct macvlan_dev *vlan = netdev_priv(dev);
		const struct macvlan_port *port = vlan->port;
		const struct macvlan_dev *dest;
		__u8 ip_summed = skb->ip_summed;

		if (vlan->mode == MACVLAN_MODE_BRIDGE) {
		const struct ethhdr eth = (void )skb->data;
		skb->ip_summed = CHECKSUM_UNNECESSARY;

		/* send to other bridge ports directly */
		if (is_multicast_ether_addr(eth->h_dest)) {
		@@ -241,6 +243,7 @@ static int macvlan_queue_xmit(struct sk_buff skb, struct net_device dev)
		}

		xmit_world:
		skb->ip_summed = ip_summed;
		skb_set_dev(skb, vlan->lowerdev);
		return dev_queue_xmit(skb);
		}

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