3 files changed, 175 insertions, 0 deletions
diff --git a/net/ethtool/features.c b/net/ethtool/features.c
index a0cc2b969053..4ac1e05684ce 100644
--- a/net/ethtool/features.c
+++ b/net/ethtool/features.c
@@ -129,3 +129,172 @@ const struct ethnl_request_ops ethnl_features_request_ops = {
 	.reply_size		= features_reply_size,
 	.fill_reply		= features_fill_reply,
 };
+
+/* FEATURES_SET */
+
+static const struct nla_policy
+features_set_policy[ETHTOOL_A_FEATURES_MAX + 1] = {
+	[ETHTOOL_A_FEATURES_UNSPEC]	= { .type = NLA_REJECT },
+	[ETHTOOL_A_FEATURES_HEADER]	= { .type = NLA_NESTED },
+	[ETHTOOL_A_FEATURES_HW]		= { .type = NLA_REJECT },
+	[ETHTOOL_A_FEATURES_WANTED]	= { .type = NLA_NESTED },
+	[ETHTOOL_A_FEATURES_ACTIVE]	= { .type = NLA_REJECT },
+	[ETHTOOL_A_FEATURES_NOCHANGE]	= { .type = NLA_REJECT },
+};
+
+static void ethnl_features_to_bitmap(unsigned long *dest, netdev_features_t val)
+{
+	const unsigned int words = BITS_TO_LONGS(NETDEV_FEATURE_COUNT);
+	unsigned int i;
+
+	bitmap_zero(dest, NETDEV_FEATURE_COUNT);
+	for (i = 0; i < words; i++)
+		dest[i] = (unsigned long)(val >> (i * BITS_PER_LONG));
+}
+
+static netdev_features_t ethnl_bitmap_to_features(unsigned long *src)
+{
+	const unsigned int nft_bits = sizeof(netdev_features_t) * BITS_PER_BYTE;
+	const unsigned int words = BITS_TO_LONGS(NETDEV_FEATURE_COUNT);
+	netdev_features_t ret = 0;
+	unsigned int i;
+
+	for (i = 0; i < words; i++)
+		ret |= (netdev_features_t)(src[i]) << (i * BITS_PER_LONG);
+	ret &= ~(netdev_features_t)0 >> (nft_bits - NETDEV_FEATURE_COUNT);
+	return ret;
+}
+
+static int features_send_reply(struct net_device *dev, struct genl_info *info,
+			       const unsigned long *wanted,
+			       const unsigned long *wanted_mask,
+			       const unsigned long *active,
+			       const unsigned long *active_mask, bool compact)
+{
+	struct sk_buff *rskb;
+	void *reply_payload;
+	int reply_len = 0;
+	int ret;
+
+	reply_len = ethnl_reply_header_size();
+	ret = ethnl_bitset_size(wanted, wanted_mask, NETDEV_FEATURE_COUNT,
+				netdev_features_strings, compact);
+	if (ret < 0)
+		goto err;
+	reply_len += ret;
+	ret = ethnl_bitset_size(active, active_mask, NETDEV_FEATURE_COUNT,
+				netdev_features_strings, compact);
+	if (ret < 0)
+		goto err;
+	reply_len += ret;
+
+	ret = -ENOMEM;
+	rskb = ethnl_reply_init(reply_len, dev, ETHTOOL_MSG_FEATURES_SET_REPLY,
+				ETHTOOL_A_FEATURES_HEADER, info,
+				&reply_payload);
+	if (!rskb)
+		goto err;
+
+	ret = ethnl_put_bitset(rskb, ETHTOOL_A_FEATURES_WANTED, wanted,
+			       wanted_mask, NETDEV_FEATURE_COUNT,
+			       netdev_features_strings, compact);
+	if (ret < 0)
+		goto nla_put_failure;
+	ret = ethnl_put_bitset(rskb, ETHTOOL_A_FEATURES_ACTIVE, active,
+			       active_mask, NETDEV_FEATURE_COUNT,
+			       netdev_features_strings, compact);
+	if (ret < 0)
+		goto nla_put_failure;
+
+	genlmsg_end(rskb, reply_payload);
+	ret = genlmsg_reply(rskb, info);
+	return ret;
+
+nla_put_failure:
+	nlmsg_free(rskb);
+	WARN_ONCE(1, "calculated message payload length (%d) not sufficient\n",
+		  reply_len);
+err:
+	GENL_SET_ERR_MSG(info, "failed to send reply message");
+	return ret;
+}
+
+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(new_active, 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];
+	struct ethnl_req_info req_info = {};
+	struct net_device *dev;
+	int ret;
+
+	ret = nlmsg_parse(info->nlhdr, GENL_HDRLEN, tb,
+			  ETHTOOL_A_FEATURES_MAX, features_set_policy,
+			  info->extack);
+	if (ret < 0)
+		return ret;
+	if (!tb[ETHTOOL_A_FEATURES_WANTED])
+		return -EINVAL;
+	ret = ethnl_parse_header_dev_get(&req_info,
+					 tb[ETHTOOL_A_FEATURES_HEADER],
+					 genl_info_net(info), info->extack,
+					 true);
+	if (ret < 0)
+		return ret;
+	dev = req_info.dev;
+
+	rtnl_lock();
+	ethnl_features_to_bitmap(old_active, dev->features);
+	ret = ethnl_parse_bitset(req_wanted, req_mask, NETDEV_FEATURE_COUNT,
+				 tb[ETHTOOL_A_FEATURES_WANTED],
+				 netdev_features_strings, info->extack);
+	if (ret < 0)
+		goto out_rtnl;
+	if (ethnl_bitmap_to_features(req_mask) & ~NETIF_F_ETHTOOL_BITS) {
+		GENL_SET_ERR_MSG(info, "attempt to change non-ethtool features");
+		ret = -EINVAL;
+		goto out_rtnl;
+	}
+
+	/* set req_wanted bits not in req_mask from old_active */
+	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;
+	}
+
+	dev->wanted_features = ethnl_bitmap_to_features(req_wanted);
+	__netdev_update_features(dev);
+	ethnl_features_to_bitmap(new_active, dev->features);
+
+	ret = 0;
+	if (!(req_info.flags & ETHTOOL_FLAG_OMIT_REPLY)) {
+		bool compact = req_info.flags & ETHTOOL_FLAG_COMPACT_BITSETS;
+
+		bitmap_xor(wanted_diff_mask, req_wanted, new_active,
+			   NETDEV_FEATURE_COUNT);
+		bitmap_xor(active_diff_mask, old_active, new_active,
+			   NETDEV_FEATURE_COUNT);
+		bitmap_and(wanted_diff_mask, wanted_diff_mask, req_mask,
+			   NETDEV_FEATURE_COUNT);
+		bitmap_and(req_wanted, req_wanted, wanted_diff_mask,
+			   NETDEV_FEATURE_COUNT);
+		bitmap_and(new_active, new_active, active_diff_mask,
+			   NETDEV_FEATURE_COUNT);
+
+		ret = features_send_reply(dev, info, req_wanted,
+					  wanted_diff_mask, new_active,
+					  active_diff_mask, compact);
+	}
+
+out_rtnl:
+	rtnl_unlock();
+	dev_put(dev);
+	return ret;
+}
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index e451a75e9577..757ea3fc98a0 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -703,6 +703,11 @@ static const struct genl_ops ethtool_genl_ops[] = {
 		.dumpit	= ethnl_default_dumpit,
 		.done	= ethnl_default_done,
 	},
+	{
+		.cmd	= ETHTOOL_MSG_FEATURES_SET,
+		.flags	= GENL_UNS_ADMIN_PERM,
+		.doit	= ethnl_set_features,
+	},
 };
 
 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index be2325ea8493..135836201e89 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -343,5 +343,6 @@ int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info);
 int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info);
 int ethnl_set_debug(struct sk_buff *skb, struct genl_info *info);
 int ethnl_set_wol(struct sk_buff *skb, struct genl_info *info);
+int ethnl_set_features(struct sk_buff *skb, struct genl_info *info);
 
 #endif /* _NET_ETHTOOL_NETLINK_H */