net: ipv4: provide __rcu annotation for ifa_list

ifa_list is protected by rcu, yet code doesn't reflect this.

Add the __rcu annotations and fix up all places that are now reported by
sparse.

I've done this in the same commit to not add intermediate patches that
result in new warnings.

Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 25 insertions, 10 deletions

diff --git a/drivers/infiniband/hw/i40iw/i40iw_utils.c b/drivers/infiniband/hw/i40iw/i40iw_utils.c
index 337410f40860..016524683e17 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_utils.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_utils.c
@@ -174,10 +174,14 @@ int i40iw_inetaddr_event(struct notifier_block *notifier,
 		rcu_read_lock();
 		in = __in_dev_get_rcu(upper_dev);
 
-		if (!in->ifa_list)
-			local_ipaddr = 0;
-		else
-			local_ipaddr = ntohl(in->ifa_list->ifa_address);
+		local_ipaddr = 0;
+		if (in) {
+			struct in_ifaddr *ifa;
+
+			ifa = rcu_dereference(in->ifa_list);
+			if (ifa)
+				local_ipaddr = ntohl(ifa->ifa_address);
+		}
 
 		rcu_read_unlock();
 	} else {
diff --git a/drivers/infiniband/hw/nes/nes.c b/drivers/infiniband/hw/nes/nes.c
index e00add6d78ec..29b324726ea6 100644
--- a/drivers/infiniband/hw/nes/nes.c
+++ b/drivers/infiniband/hw/nes/nes.c
@@ -183,7 +183,13 @@ static int nes_inetaddr_event(struct notifier_block *notifier,
 
 						rcu_read_lock();
 						in = __in_dev_get_rcu(upper_dev);
-						nesvnic->local_ipaddr = in->ifa_list->ifa_address;
+						if (in) {
+							struct in_ifaddr *ifa;
+
+							ifa = rcu_dereference(in->ifa_list);
+							if (ifa)
+								nesvnic->local_ipaddr = ifa->ifa_address;
+						}
 						rcu_read_unlock();
 					} else {
 						nesvnic->local_ipaddr = ifa->ifa_address;
diff --git a/drivers/infiniband/hw/usnic/usnic_ib_main.c b/drivers/infiniband/hw/usnic/usnic_ib_main.c
index d88d9f8a7f9a..34c1f9d6c915 100644
--- a/drivers/infiniband/hw/usnic/usnic_ib_main.c
+++ b/drivers/infiniband/hw/usnic/usnic_ib_main.c
@@ -427,11 +427,16 @@ static void *usnic_ib_device_add(struct pci_dev *dev)
 	if (netif_carrier_ok(us_ibdev->netdev))
 		usnic_fwd_carrier_up(us_ibdev->ufdev);
 
-	ind = in_dev_get(netdev);
-	if (ind->ifa_list)
-		usnic_fwd_add_ipaddr(us_ibdev->ufdev,
-				     ind->ifa_list->ifa_address);
-	in_dev_put(ind);
+	rcu_read_lock();
+	ind = __in_dev_get_rcu(netdev);
+	if (ind) {
+		const struct in_ifaddr *ifa;
+
+		ifa = rcu_dereference(ind->ifa_list);
+		if (ifa)
+			usnic_fwd_add_ipaddr(us_ibdev->ufdev, ifa->ifa_address);
+	}
+	rcu_read_unlock();
 
 	usnic_mac_ip_to_gid(us_ibdev->netdev->perm_addr,
 				us_ibdev->ufdev->inaddr, &gid.raw[0]);