decnet: Add missing neigh->ha locking to dn_neigh_output_packet()

Basically, mirror the logic in neigh_connected_output().

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 9 deletions

diff --git a/net/decnet/dn_neigh.c b/net/decnet/dn_neigh.c
index befe426491ba..ee7013f24fca 100644
--- a/net/decnet/dn_neigh.c
+++ b/net/decnet/dn_neigh.c
@@ -205,17 +205,23 @@ static int dn_neigh_output_packet(struct sk_buff *skb)
         struct neighbour *neigh = dst_get_neighbour_noref(dst);
         struct net_device *dev = neigh->dev;
         char mac_addr[ETH_ALEN];
+        unsigned int seq;
+        int err;
 
         dn_dn2eth(mac_addr, rt->rt_local_src);
-        if (dev_hard_header(skb, dev, ntohs(skb->protocol), neigh->ha,
-                            mac_addr, skb->len) >= 0)
-                return dev_queue_xmit(skb);
-
-        if (net_ratelimit())
-                printk(KERN_DEBUG "dn_neigh_output_packet: oops, can't send packet\n");
-
-        kfree_skb(skb);
-        return -EINVAL;
+        do {
+                seq = read_seqbegin(&neigh->ha_lock);
+                err = dev_hard_header(skb, dev, ntohs(skb->protocol),
+                                      neigh->ha, mac_addr, skb->len);
+        } while (read_seqretry(&neigh->ha_lock, seq));
+
+        if (err >= 0)
+                err = dev_queue_xmit(skb);
+        else {
+                kfree_skb(skb);
+                err = -EINVAL;
+        }
+        return err;
 }
 
 static int dn_long_output(struct neighbour *neigh, struct sk_buff *skb)