Merge branch 'ethtool-netlink-bug-fixes'

Maxim Mikityanskiy says:

====================
ethtool-netlink bug fixes

This series contains a few bug fixes for ethtool-netlink. These bugs are
specific for the netlink interface, and the legacy ioctl interface is
not affected. These patches aim to have the same behavior in
ethtool-netlink as in the legacy ethtool.

Please also see the sibling series for the userspace tool.

v2 changes: Added Fixes tags.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

net/ethtool/features.c

@@ -224,7 +224,9 @@ int ethnl_set_features(struct sk_buff *skb, struct genl_info *info)
 	DECLARE_BITMAP(wanted_diff_mask, NETDEV_FEATURE_COUNT);
 	DECLARE_BITMAP(active_diff_mask, NETDEV_FEATURE_COUNT);
 	DECLARE_BITMAP(old_active, NETDEV_FEATURE_COUNT);
+	DECLARE_BITMAP(old_wanted, NETDEV_FEATURE_COUNT);
 	DECLARE_BITMAP(new_active, NETDEV_FEATURE_COUNT);
+	DECLARE_BITMAP(new_wanted, NETDEV_FEATURE_COUNT);
 	DECLARE_BITMAP(req_wanted, NETDEV_FEATURE_COUNT);
 	DECLARE_BITMAP(req_mask, NETDEV_FEATURE_COUNT);
 	struct nlattr *tb[ETHTOOL_A_FEATURES_MAX + 1];
@@ -250,6 +252,7 @@ int ethnl_set_features(struct sk_buff *skb, struct genl_info *info)
 
 	rtnl_lock();
 	ethnl_features_to_bitmap(old_active, dev->features);
+	ethnl_features_to_bitmap(old_wanted, dev->wanted_features);
 	ret = ethnl_parse_bitset(req_wanted, req_mask, NETDEV_FEATURE_COUNT,
 				 tb[ETHTOOL_A_FEATURES_WANTED],
 				 netdev_features_strings, info->extack);
@@ -261,17 +264,15 @@ int ethnl_set_features(struct sk_buff *skb, struct genl_info *info)
 		goto out_rtnl;
 	}
 
-	/* set req_wanted bits not in req_mask from old_active */
+	/* set req_wanted bits not in req_mask from old_wanted */
 	bitmap_and(req_wanted, req_wanted, req_mask, NETDEV_FEATURE_COUNT);
-	bitmap_andnot(new_active, old_active, req_mask, NETDEV_FEATURE_COUNT);
-	bitmap_or(req_wanted, new_active, req_wanted, NETDEV_FEATURE_COUNT);
-	if (bitmap_equal(req_wanted, old_active, NETDEV_FEATURE_COUNT)) {
-		ret = 0;
-		goto out_rtnl;
+	bitmap_andnot(new_wanted, old_wanted, req_mask, NETDEV_FEATURE_COUNT);
+	bitmap_or(req_wanted, new_wanted, req_wanted, NETDEV_FEATURE_COUNT);
+	if (!bitmap_equal(req_wanted, old_wanted, NETDEV_FEATURE_COUNT)) {
+		dev->wanted_features &= ~dev->hw_features;
+		dev->wanted_features |= ethnl_bitmap_to_features(req_wanted) & dev->hw_features;
+		__netdev_update_features(dev);
 	}
-
-	dev->wanted_features = ethnl_bitmap_to_features(req_wanted);
-	__netdev_update_features(dev);
 	ethnl_features_to_bitmap(new_active, dev->features);
 	mod = !bitmap_equal(old_active, new_active, NETDEV_FEATURE_COUNT);