net: core: Convert dev_set_mac_address() to struct sockaddr_storage

All users of dev_set_mac_address() are now using a struct sockaddr_storage.
Convert the internal data type to struct sockaddr_storage, drop the casts,
and update pointer types.

Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20250521204619.2301870-6-kees@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: kees

drivers/net/bonding/bond_alb.c

@@ -1035,7 +1035,7 @@ static int alb_set_slave_mac_addr(struct slave *slave, const u8 addr[],
 	 */
 	memcpy(ss.__data, addr, len);
 	ss.ss_family = dev->type;
-	if (dev_set_mac_address(dev, (struct sockaddr *)&ss, NULL)) {
+	if (dev_set_mac_address(dev, &ss, NULL)) {
 		slave_err(slave->bond->dev, dev, "dev_set_mac_address on slave failed! ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n");
 		return -EOPNOTSUPP;
 	}
@@ -1273,8 +1273,7 @@ static int alb_set_mac_address(struct bonding *bond, void *addr)
 			break;
 		bond_hw_addr_copy(tmp_addr, rollback_slave->dev->dev_addr,
 				  rollback_slave->dev->addr_len);
-		dev_set_mac_address(rollback_slave->dev,
-				    (struct sockaddr *)&ss, NULL);
+		dev_set_mac_address(rollback_slave->dev, &ss, NULL);
 		dev_addr_set(rollback_slave->dev, tmp_addr);
 	}
 
@@ -1763,8 +1762,7 @@ void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave
 				  bond->dev->addr_len);
 		ss.ss_family = bond->dev->type;
 		/* we don't care if it can't change its mac, best effort */
-		dev_set_mac_address(new_slave->dev, (struct sockaddr *)&ss,
-				    NULL);
+		dev_set_mac_address(new_slave->dev, &ss, NULL);
 
 		dev_addr_set(new_slave->dev, tmp_addr);
 	}

drivers/net/bonding/bond_main.c

@@ -1112,8 +1112,7 @@ static void bond_do_fail_over_mac(struct bonding *bond,
 			ss.ss_family = bond->dev->type;
 		}
 
-		rv = dev_set_mac_address(new_active->dev,
-					 (struct sockaddr *)&ss, NULL);
+		rv = dev_set_mac_address(new_active->dev, &ss, NULL);
 		if (rv) {
 			slave_err(bond->dev, new_active->dev, "Error %d setting MAC of new active slave\n",
 				  -rv);
@@ -1127,8 +1126,7 @@ static void bond_do_fail_over_mac(struct bonding *bond,
 				  new_active->dev->addr_len);
 		ss.ss_family = old_active->dev->type;
 
-		rv = dev_set_mac_address(old_active->dev,
-					 (struct sockaddr *)&ss, NULL);
+		rv = dev_set_mac_address(old_active->dev, &ss, NULL);
 		if (rv)
 			slave_err(bond->dev, old_active->dev, "Error %d setting MAC of old active slave\n",
 				  -rv);
@@ -2127,7 +2125,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 	}
 
 	ss.ss_family = slave_dev->type;
-	res = dev_set_mac_address(slave_dev, (struct sockaddr *)&ss, extack);
+	res = dev_set_mac_address(slave_dev, &ss, extack);
 	if (res) {
 		slave_err(bond_dev, slave_dev, "Error %d calling set_mac_address\n", res);
 		goto err_restore_mtu;
@@ -2455,7 +2453,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 		bond_hw_addr_copy(ss.__data, new_slave->perm_hwaddr,
 				  new_slave->dev->addr_len);
 		ss.ss_family = slave_dev->type;
-		dev_set_mac_address(slave_dev, (struct sockaddr *)&ss, NULL);
+		dev_set_mac_address(slave_dev, &ss, NULL);
 	}
 
 err_restore_mtu:
@@ -2649,7 +2647,7 @@ static int __bond_release_one(struct net_device *bond_dev,
 		bond_hw_addr_copy(ss.__data, slave->perm_hwaddr,
 				  slave->dev->addr_len);
 		ss.ss_family = slave_dev->type;
-		dev_set_mac_address(slave_dev, (struct sockaddr *)&ss, NULL);
+		dev_set_mac_address(slave_dev, &ss, NULL);
 	}
 
 	if (unregister) {
@@ -4936,8 +4934,7 @@ static int bond_set_mac_address(struct net_device *bond_dev, void *addr)
 		if (rollback_slave == slave)
 			break;
 
-		tmp_res = dev_set_mac_address(rollback_slave->dev,
-					      (struct sockaddr *)&tmp_ss, NULL);
+		tmp_res = dev_set_mac_address(rollback_slave->dev, &tmp_ss, NULL);
 		if (tmp_res) {
 			slave_dbg(bond_dev, rollback_slave->dev, "%s: unwind err %d\n",
 				   __func__, tmp_res);

drivers/net/hyperv/netvsc_drv.c

@@ -1371,7 +1371,7 @@ static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
 	struct net_device_context *ndc = netdev_priv(ndev);
 	struct net_device *vf_netdev = rtnl_dereference(ndc->vf_netdev);
 	struct netvsc_device *nvdev = rtnl_dereference(ndc->nvdev);
-	struct sockaddr *addr = p;
+	struct sockaddr_storage *addr = p;
 	int err;
 
 	err = eth_prepare_mac_addr_change(ndev, p);
@@ -1387,12 +1387,12 @@ static int netvsc_set_mac_addr(struct net_device *ndev, void *p)
 			return err;
 	}
 
-	err = rndis_filter_set_device_mac(nvdev, addr->sa_data);
+	err = rndis_filter_set_device_mac(nvdev, addr->__data);
 	if (!err) {
 		eth_commit_mac_addr_change(ndev, p);
 	} else if (vf_netdev) {
 		/* rollback change on VF */
-		memcpy(addr->sa_data, ndev->dev_addr, ETH_ALEN);
+		memcpy(addr->__data, ndev->dev_addr, ETH_ALEN);
 		dev_set_mac_address(vf_netdev, addr, NULL);
 	}
 

drivers/net/macvlan.c

@@ -754,24 +754,24 @@ static int macvlan_sync_address(struct net_device *dev,
 static int macvlan_set_mac_address(struct net_device *dev, void *p)
 {
 	struct macvlan_dev *vlan = netdev_priv(dev);
-	struct sockaddr *addr = p;
+	struct sockaddr_storage *addr = p;
 
-	if (!is_valid_ether_addr(addr->sa_data))
+	if (!is_valid_ether_addr(addr->__data))
 		return -EADDRNOTAVAIL;
 
 	/* If the addresses are the same, this is a no-op */
-	if (ether_addr_equal(dev->dev_addr, addr->sa_data))
+	if (ether_addr_equal(dev->dev_addr, addr->__data))
 		return 0;
 
 	if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
 		macvlan_set_addr_change(vlan->port);
 		return dev_set_mac_address(vlan->lowerdev, addr, NULL);
 	}
 
-	if (macvlan_addr_busy(vlan->port, addr->sa_data))
+	if (macvlan_addr_busy(vlan->port, addr->__data))
 		return -EADDRINUSE;
 
-	return macvlan_sync_address(dev, addr->sa_data);
+	return macvlan_sync_address(dev, addr->__data);
 }
 
 static void macvlan_change_rx_flags(struct net_device *dev, int change)
@@ -1295,11 +1295,11 @@ static void macvlan_port_destroy(struct net_device *dev)
 	 */
 	if (macvlan_passthru(port) &&
 	    !ether_addr_equal(port->dev->dev_addr, port->perm_addr)) {
-		struct sockaddr sa;
+		struct sockaddr_storage ss;
 
-		sa.sa_family = port->dev->type;
-		memcpy(&sa.sa_data, port->perm_addr, port->dev->addr_len);
-		dev_set_mac_address(port->dev, &sa, NULL);
+		ss.ss_family = port->dev->type;
+		memcpy(&ss.__data, port->perm_addr, port->dev->addr_len);
+		dev_set_mac_address(port->dev, &ss, NULL);
 	}
 
 	kfree(port);

drivers/net/team/team_core.c

@@ -55,7 +55,7 @@ static int __set_port_dev_addr(struct net_device *port_dev,
 
 	memcpy(addr.__data, dev_addr, port_dev->addr_len);
 	addr.ss_family = port_dev->type;
-	return dev_set_mac_address(port_dev, (struct sockaddr *)&addr, NULL);
+	return dev_set_mac_address(port_dev, &addr, NULL);
 }
 
 static int team_port_set_orig_dev_addr(struct team_port *port)

drivers/net/usb/r8152.c

@@ -8432,7 +8432,7 @@ static int rtl8152_post_reset(struct usb_interface *intf)
 
 	/* reset the MAC address in case of policy change */
 	if (determine_ethernet_addr(tp, &ss) >= 0)
-		dev_set_mac_address(tp->netdev, (struct sockaddr *)&ss, NULL);
+		dev_set_mac_address(tp->netdev, &ss, NULL);
 
 	netdev = tp->netdev;
 	if (!netif_running(netdev))

include/linux/netdevice.h

@@ -4214,7 +4214,7 @@ int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr,
 			      struct netlink_ext_ack *extack);
 int netif_set_mac_address(struct net_device *dev, struct sockaddr_storage *ss,
 			  struct netlink_ext_ack *extack);
-int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa,
+int dev_set_mac_address(struct net_device *dev, struct sockaddr_storage *ss,
 			struct netlink_ext_ack *extack);
 int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa,
 			     struct netlink_ext_ack *extack);

net/core/dev.c

@@ -9697,6 +9697,7 @@ int netif_set_mac_address(struct net_device *dev, struct sockaddr_storage *ss,
 
 DECLARE_RWSEM(dev_addr_sem);
 
+/* "sa" is a true struct sockaddr with limited "sa_data" member. */
 int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name)
 {
 	size_t size = sizeof(sa->sa_data_min);

net/core/dev_api.c

@@ -319,20 +319,20 @@ EXPORT_SYMBOL(dev_set_allmulti);
 /**
  * dev_set_mac_address() - change Media Access Control Address
  * @dev: device
- * @sa: new address
+ * @ss: new address
  * @extack: netlink extended ack
  *
  * Change the hardware (MAC) address of the device
  *
  * Return: 0 on success, -errno on failure.
  */
-int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa,
+int dev_set_mac_address(struct net_device *dev, struct sockaddr_storage *ss,
 			struct netlink_ext_ack *extack)
 {
 	int ret;
 
 	netdev_lock_ops(dev);
-	ret = netif_set_mac_address(dev, (struct sockaddr_storage *)sa, extack);
+	ret = netif_set_mac_address(dev, ss, extack);
 	netdev_unlock_ops(dev);
 
 	return ret;

net/ieee802154/nl-phy.c

@@ -234,7 +234,7 @@ int ieee802154_add_iface(struct sk_buff *skb, struct genl_info *info)
 		 * dev_set_mac_address require RTNL_LOCK
 		 */
 		rtnl_lock();
-		rc = dev_set_mac_address(dev, (struct sockaddr *)&addr, NULL);
+		rc = dev_set_mac_address(dev, &addr, NULL);
 		rtnl_unlock();
 		if (rc)
 			goto dev_unregister;