Merge branch 'rtnetlink-add-missing-attributes-in-if_nlmsg_size'

Sabrina Dubroca says:

====================
rtnetlink: add missing attributes in if_nlmsg_size

Once again we have some attributes added by rtnl_fill_ifinfo() that
aren't counted in if_nlmsg_size().
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: kuba-moo

net/core/rtnetlink.c

@@ -707,11 +707,14 @@ static size_t rtnl_link_get_slave_info_data_size(const struct net_device *dev)
 		goto out;
 
 	ops = master_dev->rtnl_link_ops;
-	if (!ops || !ops->get_slave_size)
+	if (!ops)
+		goto out;
+	size += nla_total_size(strlen(ops->kind) + 1);  /* IFLA_INFO_SLAVE_KIND */
+	if (!ops->get_slave_size)
 		goto out;
 	/* IFLA_INFO_SLAVE_DATA + nested data */
-	size = nla_total_size(sizeof(struct nlattr)) +
-	       ops->get_slave_size(master_dev, dev);
+	size += nla_total_size(sizeof(struct nlattr)) +
+		ops->get_slave_size(master_dev, dev);
 
 out:
 	rcu_read_unlock();
@@ -1267,6 +1270,21 @@ static size_t rtnl_dpll_pin_size(const struct net_device *dev)
 	return size;
 }
 
+static size_t rtnl_dev_parent_size(const struct net_device *dev)
+{
+	size_t size = 0;
+
+	/* IFLA_PARENT_DEV_NAME */
+	if (dev->dev.parent)
+		size += nla_total_size(strlen(dev_name(dev->dev.parent)) + 1);
+
+	/* IFLA_PARENT_DEV_BUS_NAME */
+	if (dev->dev.parent && dev->dev.parent->bus)
+		size += nla_total_size(strlen(dev->dev.parent->bus->name) + 1);
+
+	return size;
+}
+
 static noinline size_t if_nlmsg_size(const struct net_device *dev,
 				     u32 ext_filter_mask)
 {
@@ -1328,6 +1346,7 @@ static noinline size_t if_nlmsg_size(const struct net_device *dev,
 	       + nla_total_size(8)  /* IFLA_MAX_PACING_OFFLOAD_HORIZON */
 	       + nla_total_size(2)  /* IFLA_HEADROOM */
 	       + nla_total_size(2)  /* IFLA_TAILROOM */
+	       + rtnl_dev_parent_size(dev)
 	       + 0;
 
 	if (!(ext_filter_mask & RTEXT_FILTER_SKIP_STATS))