ipv4: ip_ptr cleanups

dev->ip_ptr is protected by rtnl and rcu.

Yet some places dont use appropriate primitives and/or locking rules.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 16 insertions, 7 deletions

diff --git a/drivers/net/plip.c b/drivers/net/plip.c
index 7e82a82422cf..ca4df7f4cf21 100644
--- a/drivers/net/plip.c
+++ b/drivers/net/plip.c
@@ -995,8 +995,10 @@ plip_tx_packet(struct sk_buff *skb, struct net_device *dev)
 static void
 plip_rewrite_address(const struct net_device *dev, struct ethhdr *eth)
 {
-	const struct in_device *in_dev = dev->ip_ptr;
+	const struct in_device *in_dev;
 
+	rcu_read_lock();
+	in_dev = __in_dev_get_rcu(dev);
 	if (in_dev) {
 		/* Any address will do - we take the first */
 		const struct in_ifaddr *ifa = in_dev->ifa_list;
@@ -1006,6 +1008,7 @@ plip_rewrite_address(const struct net_device *dev, struct ethhdr *eth)
 			memcpy(eth->h_dest+2, &ifa->ifa_address, 4);
 		}
 	}
+	rcu_read_unlock();
 }
 
 static int
@@ -1088,7 +1091,8 @@ plip_open(struct net_device *dev)
 	   when the device address isn't identical to the address of a
 	   received frame, the kernel incorrectly drops it).             */
 
-	if ((in_dev=dev->ip_ptr) != NULL) {
+	in_dev=__in_dev_get_rtnl(dev);
+	if (in_dev) {
 		/* Any address will do - we take the first. We already
 		   have the first two bytes filled with 0xfc, from
 		   plip_init_dev(). */
diff --git a/drivers/net/via-velocity.h b/drivers/net/via-velocity.h
index f7b33ae7a703..b5e120b0074b 100644
--- a/drivers/net/via-velocity.h
+++ b/drivers/net/via-velocity.h
@@ -1504,22 +1504,25 @@ struct velocity_info {
  *	addresses on this chain then we use the first - multi-IP WOL is not
  *	supported.
  *
- *	CHECK ME: locking
  */
 
 static inline int velocity_get_ip(struct velocity_info *vptr)
 {
-	struct in_device *in_dev = (struct in_device *) vptr->dev->ip_ptr;
+	struct in_device *in_dev;
 	struct in_ifaddr *ifa;
+	int res = -ENOENT;
 
+	rcu_read_lock();
+	in_dev = __in_dev_get_rcu(vptr->dev);
 	if (in_dev != NULL) {
 		ifa = (struct in_ifaddr *) in_dev->ifa_list;
 		if (ifa != NULL) {
 			memcpy(vptr->ip_addr, &ifa->ifa_address, 4);
-			return 0;
+			res = 0;
 		}
 	}
-	return -ENOENT;
+	rcu_read_unlock();
+	return res;
 }
 
 /**
diff --git a/drivers/net/wan/hdlc_cisco.c b/drivers/net/wan/hdlc_cisco.c
index b38ffa149aba..b1e5e5b69c2a 100644
--- a/drivers/net/wan/hdlc_cisco.c
+++ b/drivers/net/wan/hdlc_cisco.c
@@ -191,7 +191,8 @@ static int cisco_rx(struct sk_buff *skb)
 
 		switch (ntohl (cisco_data->type)) {
 		case CISCO_ADDR_REQ: /* Stolen from syncppp.c :-) */
-			in_dev = dev->ip_ptr;
+			rcu_read_lock();
+			in_dev = __in_dev_get_rcu(dev);
 			addr = 0;
 			mask = ~cpu_to_be32(0); /* is the mask correct? */
 
@@ -211,6 +212,7 @@ static int cisco_rx(struct sk_buff *skb)
 				cisco_keepalive_send(dev, CISCO_ADDR_REPLY,
 						     addr, mask);
 			}
+			rcu_read_unlock();
 			dev_kfree_skb_any(skb);
 			return NET_RX_SUCCESS;