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 7e82a82422c..ca4df7f4cf2 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 f7b33ae7a70..b5e120b0074 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 b38ffa149ab..b1e5e5b69c2 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;