net: annotate data-races around dev->if_port

Various ndo_set_config() methods can change dev->if_port

dev->if_port is going to be read locklessly from
rtnl_fill_link_ifmap().

Add corresponding WRITE_ONCE() on writer sides.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240507184144.1230469-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: edumazet

drivers/net/ethernet/3com/3c589_cs.c

@@ -502,7 +502,7 @@ static int el3_config(struct net_device *dev, struct ifmap *map)
 {
 	if ((map->port != (u_char)(-1)) && (map->port != dev->if_port)) {
 		if (map->port <= 3) {
-			dev->if_port = map->port;
+			WRITE_ONCE(dev->if_port, map->port);
 			netdev_info(dev, "switched to %s port\n", if_names[dev->if_port]);
 			tc589_set_xcvr(dev, dev->if_port);
 		} else {

drivers/net/ethernet/8390/etherh.c

@@ -258,7 +258,7 @@ static int etherh_set_config(struct net_device *dev, struct ifmap *map)
 		 * media type, turn off automedia detection.
 		 */
 		dev->flags &= ~IFF_AUTOMEDIA;
-		dev->if_port = map->port;
+		WRITE_ONCE(dev->if_port, map->port);
 		break;
 
 	default:

drivers/net/ethernet/8390/pcnet_cs.c

@@ -994,7 +994,7 @@ static int set_config(struct net_device *dev, struct ifmap *map)
 	    return -EOPNOTSUPP;
 	else if ((map->port < 1) || (map->port > 2))
 	    return -EINVAL;
-	dev->if_port = map->port;
+	WRITE_ONCE(dev->if_port, map->port);
 	netdev_info(dev, "switched to %s port\n", if_names[dev->if_port]);
 	NS8390_init(dev, 1);
     }

drivers/net/ethernet/amd/nmclan_cs.c

@@ -760,7 +760,7 @@ static int mace_config(struct net_device *dev, struct ifmap *map)
 {
   if ((map->port != (u_char)(-1)) && (map->port != dev->if_port)) {
     if (map->port <= 2) {
-      dev->if_port = map->port;
+      WRITE_ONCE(dev->if_port, map->port);
       netdev_info(dev, "switched to %s port\n", if_names[dev->if_port]);
     } else
       return -EINVAL;

drivers/net/ethernet/sis/sis900.c

@@ -2273,7 +2273,7 @@ static int sis900_set_config(struct net_device *dev, struct ifmap *map)
 		 * (which seems to be different from the ifport(pcmcia) definition) */
 		switch(map->port){
 		case IF_PORT_UNKNOWN: /* use auto here */
-			dev->if_port = map->port;
+			WRITE_ONCE(dev->if_port, map->port);
 			/* we are going to change the media type, so the Link
 			 * will be temporary down and we need to reflect that
 			 * here. When the Link comes up again, it will be
@@ -2294,7 +2294,7 @@ static int sis900_set_config(struct net_device *dev, struct ifmap *map)
 			break;
 
 		case IF_PORT_10BASET: /* 10BaseT */
-			dev->if_port = map->port;
+			WRITE_ONCE(dev->if_port, map->port);
 
 			/* we are going to change the media type, so the Link
 			 * will be temporary down and we need to reflect that
@@ -2315,7 +2315,7 @@ static int sis900_set_config(struct net_device *dev, struct ifmap *map)
 
 		case IF_PORT_100BASET: /* 100BaseT */
 		case IF_PORT_100BASETX: /* 100BaseTx */
-			dev->if_port = map->port;
+			WRITE_ONCE(dev->if_port, map->port);
 
 			/* we are going to change the media type, so the Link
 			 * will be temporary down and we need to reflect that

drivers/net/ethernet/smsc/smc91c92_cs.c

@@ -1595,7 +1595,7 @@ static int s9k_config(struct net_device *dev, struct ifmap *map)
 	    return -EOPNOTSUPP;
 	else if (map->port > 2)
 	    return -EINVAL;
-	dev->if_port = map->port;
+	WRITE_ONCE(dev->if_port, map->port);
 	netdev_info(dev, "switched to %s port\n", if_names[dev->if_port]);
 	smc_reset(dev);
     }

drivers/net/ethernet/xircom/xirc2ps_cs.c

@@ -1366,10 +1366,10 @@ do_config(struct net_device *dev, struct ifmap *map)
 	    return -EINVAL;
 	if (!map->port) {
 	    local->probe_port = 1;
-	    dev->if_port = 1;
+	    WRITE_ONCE(dev->if_port, 1);
 	} else {
 	    local->probe_port = 0;
-	    dev->if_port = map->port;
+	    WRITE_ONCE(dev->if_port, map->port);
 	}
 	netdev_info(dev, "switching to %s port\n", if_names[dev->if_port]);
 	do_reset(dev,1);  /* not the fine way :-) */