1 files changed, 47 insertions, 23 deletions

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index 0ea29345eb2e..dff08842f26d 100644
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -43,8 +43,8 @@
 #define DRV_VERSION	"1.0"
 
 struct net_vrf {
-	struct rtable           *rth;
-	struct rt6_info		*rt6;
+	struct rtable __rcu	*rth;
+	struct rt6_info	__rcu	*rt6;
 	u32                     tb_id;
 };
 
@@ -273,10 +273,15 @@ static int vrf_output6(struct net *net, struct sock *sk, struct sk_buff *skb)
 			    !(IP6CB(skb)->flags & IP6SKB_REROUTED));
 }
 
+/* holding rtnl */
 static void vrf_rt6_release(struct net_vrf *vrf)
 {
-	dst_release(&vrf->rt6->dst);
-	vrf->rt6 = NULL;
+	struct rt6_info *rt6 = rtnl_dereference(vrf->rt6);
+
+	rcu_assign_pointer(vrf->rt6, NULL);
+
+	if (rt6)
+		dst_release(&rt6->dst);
 }
 
 static int vrf_rt6_create(struct net_device *dev)
@@ -300,7 +305,8 @@ static int vrf_rt6_create(struct net_device *dev)
 
 	rt6->rt6i_table = rt6i_table;
 	rt6->dst.output	= vrf_output6;
-	vrf->rt6 = rt6;
+	rcu_assign_pointer(vrf->rt6, rt6);
+
 	rc = 0;
 out:
 	return rc;
@@ -374,29 +380,35 @@ static int vrf_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 			    !(IPCB(skb)->flags & IPSKB_REROUTED));
 }
 
+/* holding rtnl */
 static void vrf_rtable_release(struct net_vrf *vrf)
 {
-	struct dst_entry *dst = (struct dst_entry *)vrf->rth;
+	struct rtable *rth = rtnl_dereference(vrf->rth);
+
+	rcu_assign_pointer(vrf->rth, NULL);
 
-	dst_release(dst);
-	vrf->rth = NULL;
+	if (rth)
+		dst_release(&rth->dst);
 }
 
-static struct rtable *vrf_rtable_create(struct net_device *dev)
+static int vrf_rtable_create(struct net_device *dev)
 {
 	struct net_vrf *vrf = netdev_priv(dev);
 	struct rtable *rth;
 
 	if (!fib_new_table(dev_net(dev), vrf->tb_id))
-		return NULL;
+		return -ENOMEM;
 
 	rth = rt_dst_alloc(dev, 0, RTN_UNICAST, 1, 1, 0);
-	if (rth) {
-		rth->dst.output	= vrf_output;
-		rth->rt_table_id = vrf->tb_id;
-	}
+	if (!rth)
+		return -ENOMEM;
 
-	return rth;
+	rth->dst.output	= vrf_output;
+	rth->rt_table_id = vrf->tb_id;
+
+	rcu_assign_pointer(vrf->rth, rth);
+
+	return 0;
 }
 
 /**************************** device handling ********************/
@@ -484,8 +496,7 @@ static int vrf_dev_init(struct net_device *dev)
 		goto out_nomem;
 
 	/* create the default dst which points back to us */
-	vrf->rth = vrf_rtable_create(dev);
-	if (!vrf->rth)
+	if (vrf_rtable_create(dev) != 0)
 		goto out_stats;
 
 	if (vrf_rt6_create(dev) != 0)
@@ -528,8 +539,13 @@ static struct rtable *vrf_get_rtable(const struct net_device *dev,
 	if (!(fl4->flowi4_flags & FLOWI_FLAG_L3MDEV_SRC)) {
 		struct net_vrf *vrf = netdev_priv(dev);
 
-		rth = vrf->rth;
-		dst_hold(&rth->dst);
+		rcu_read_lock();
+
+		rth = rcu_dereference(vrf->rth);
+		if (likely(rth))
+			dst_hold(&rth->dst);
+
+		rcu_read_unlock();
 	}
 
 	return rth;
@@ -665,16 +681,24 @@ static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
 static struct dst_entry *vrf_get_rt6_dst(const struct net_device *dev,
 					 const struct flowi6 *fl6)
 {
-	struct rt6_info *rt = NULL;
+	struct dst_entry *dst = NULL;
 
 	if (!(fl6->flowi6_flags & FLOWI_FLAG_L3MDEV_SRC)) {
 		struct net_vrf *vrf = netdev_priv(dev);
+		struct rt6_info *rt;
+
+		rcu_read_lock();
+
+		rt = rcu_dereference(vrf->rt6);
+		if (likely(rt)) {
+			dst = &rt->dst;
+			dst_hold(dst);
+		}
 
-		rt = vrf->rt6;
-		dst_hold(&rt->dst);
+		rcu_read_unlock();
 	}
 
-	return (struct dst_entry *)rt;
+	return dst;
 }
 #endif