Merge branch 'virtio_net-ethtool-validation'

Nikolay Aleksandrov says:

====================
virtio_net: better ethtool setting validation

This small set is a follow-up for the recent patches that added ethtool
get/set settings. Patch 1 changes the speed validation routine to check
if the speed is between 0 and INT_MAX (or SPEED_UNKNOWN) and patch 2 adds
port validation to virtio_net and better validation comment.

This set is on top of Michael's patch which explains that speeds from 0
to INT_MAX are valid:
http://patchwork.ozlabs.org/patch/578911/
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/virtio_net.c

@@ -1386,11 +1386,13 @@ static bool virtnet_validate_ethtool_cmd(const struct ethtool_cmd *cmd)
 	struct ethtool_cmd diff1 = *cmd;
 	struct ethtool_cmd diff2 = {};
 
-	/* advertising and cmd are usually set, ignore port because we set it */
+	/* cmd is always set so we need to clear it, validate the port type
+	 * and also without autonegotiation we can ignore advertising
+	 */
 	ethtool_cmd_speed_set(&diff1, 0);
+	diff2.port = PORT_OTHER;
 	diff1.advertising = 0;
 	diff1.duplex = 0;
-	diff1.port = 0;
 	diff1.cmd = 0;
 
 	return !memcmp(&diff1, &diff2, sizeof(diff1));

include/uapi/linux/ethtool.h

@@ -1377,24 +1377,7 @@ enum ethtool_sfeatures_retval_bits {
 
 static inline int ethtool_validate_speed(__u32 speed)
 {
-	switch (speed) {
-	case SPEED_10:
-	case SPEED_100:
-	case SPEED_1000:
-	case SPEED_2500:
-	case SPEED_5000:
-	case SPEED_10000:
-	case SPEED_20000:
-	case SPEED_25000:
-	case SPEED_40000:
-	case SPEED_50000:
-	case SPEED_56000:
-	case SPEED_100000:
-	case SPEED_UNKNOWN:
-		return 1;
-	}
-
-	return 0;
+	return speed <= INT_MAX || speed == SPEED_UNKNOWN;
 }
 
 /* Duplex, half or full. */