Re: [PATCH net] net: fix sysfs symlinks of adjacent devices

[David Miller <davem@davemloft.net>]

From: Vlad Yasevich <vyasevich@gmail.com>
Date: Fri, 12 Sep 2014 09:33:39 -0400

> Looking over the code, it might make sense to move all the net_eq checks
> into adjacent_sysfs calls so as to consolidate them.  I haven't audited
> all code paths, but at first glance it should do the right thing.
> 
> What do you think?

Agreed, let's do the following then?

diff --git a/net/core/dev.c b/net/core/dev.c
index ab9a165..a70e49e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4809,9 +4809,14 @@ static void netdev_adjacent_sysfs_del(struct net_device *dev,
 	sysfs_remove_link(&(dev->dev.kobj), linkname);
 }
 
-#define netdev_adjacent_is_neigh_list(dev, dev_list) \
-		(dev_list == &dev->adj_list.upper || \
-		 dev_list == &dev->adj_list.lower)
+static bool netdev_adjacent_is_neigh_list(struct net_device *dev,
+					  struct net_device *adj_dev,
+					  struct list_head *dev_list)
+{
+	return (dev_list == &dev->adj_list.upper ||
+		dev_list == &dev->adj_list.lower) &&
+		net_eq(dev_net(dev), dev_net(adj_dev));
+}
 
 static int __netdev_adjacent_dev_insert(struct net_device *dev,
 					struct net_device *adj_dev,
@@ -4841,7 +4846,7 @@ static int __netdev_adjacent_dev_insert(struct net_device *dev,
 	pr_debug("dev_hold for %s, because of link added from %s to %s\n",
 		 adj_dev->name, dev->name, adj_dev->name);
 
-	if (netdev_adjacent_is_neigh_list(dev, dev_list)) {
+	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
 		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
 		if (ret)
 			goto free_adj;
@@ -4862,7 +4867,7 @@ static int __netdev_adjacent_dev_insert(struct net_device *dev,
 	return 0;
 
 remove_symlinks:
-	if (netdev_adjacent_is_neigh_list(dev, dev_list))
+	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
 		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
 free_adj:
 	kfree(adj);
@@ -4895,8 +4900,7 @@ static void __netdev_adjacent_dev_remove(struct net_device *dev,
 	if (adj->master)
 		sysfs_remove_link(&(dev->dev.kobj), "master");
 
-	if (netdev_adjacent_is_neigh_list(dev, dev_list) &&
-	    net_eq(dev_net(dev),dev_net(adj_dev)))
+	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
 		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
 
 	list_del_rcu(&adj->list);