net: ethtool: Return -EOPNOTSUPP if user space tries to read EEPROM w…

…ith lengh 0 If a driver supports reading EEPROM but no EEPROM is installed in the system, the driver's get_eeprom_len function returns 0. ethtool will subsequently try to read that zero-length EEPROM anyway. If the driver does not support EEPROM access at all, this operation will return -EOPNOTSUPP. If the driver does support EEPROM access but no EEPROM is installed, the operation will return -EINVAL. Return -EOPNOTSUPP in both cases for consistency. Signed-off-by: Guenter Roeck <[email protected]> Tested-by: Andrew Lunn <[email protected]> Signed-off-by: David S. Miller <[email protected]>
josf · Oct 31, 2014 · e0fb6fb · e0fb6fb
1 parent 1e19e08
commit e0fb6fb
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/net/core/ethtool.c b/net/core/ethtool.c
@@ -1036,7 +1036,8 @@ static int ethtool_get_eeprom(struct net_device *dev, void __user *useraddr)
 {
 	const struct ethtool_ops *ops = dev->ethtool_ops;
 
-	if (!ops->get_eeprom || !ops->get_eeprom_len)
+	if (!ops->get_eeprom || !ops->get_eeprom_len ||
+	    !ops->get_eeprom_len(dev))
 		return -EOPNOTSUPP;
 
 	return ethtool_get_any_eeprom(dev, useraddr, ops->get_eeprom,
@@ -1052,7 +1053,8 @@ static int ethtool_set_eeprom(struct net_device *dev, void __user *useraddr)
 	u8 *data;
 	int ret = 0;
 
-	if (!ops->set_eeprom || !ops->get_eeprom_len)
+	if (!ops->set_eeprom || !ops->get_eeprom_len ||
+	    !ops->get_eeprom_len(dev))
 		return -EOPNOTSUPP;
 
 	if (copy_from_user(&eeprom, useraddr, sizeof(eeprom)))