vlan: fix a race in egress prio management

[pandora-kernel.git] / net / 8021q / vlan_dev.c

diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index bc25286..b40d3da 100644 (file)
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -72,6 +72,8 @@ vlan_dev_get_egress_qos_mask(struct net_device *dev, struct sk_buff *skb)
 {
        struct vlan_priority_tci_mapping *mp;
 
+       smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */
+
        mp = vlan_dev_info(dev)->egress_priority_map[(skb->priority & 0xF)];
        while (mp) {
                if (mp->priority == skb->priority) {
@@ -156,7 +158,7 @@ static netdev_tx_t vlan_dev_hard_start_xmit(struct sk_buff *skb,
                skb = __vlan_hwaccel_put_tag(skb, vlan_tci);
        }
 
-       skb_set_dev(skb, vlan_dev_info(dev)->real_dev);
+       skb->dev = vlan_dev_info(dev)->real_dev;
        len = skb->len;
        ret = dev_queue_xmit(skb);
 
@@ -232,6 +234,11 @@ int vlan_dev_set_egress_priority(const struct net_device *dev,
        np->next = mp;
        np->priority = skb_prio;
        np->vlan_qos = vlan_qos;
+       /* Before inserting this element in hash table, make sure all its fields
+        * are committed to memory.
+        * coupled with smp_rmb() in vlan_dev_get_egress_qos_mask()
+        */
+       smp_wmb();
        vlan->egress_priority_map[skb_prio & 0xF] = np;
        if (vlan_qos)
                vlan->nr_egress_mappings++;