net: account alternate interface name memory

George reports that altnames can eat up kernel memory.
We should charge that memory appropriately.
Reported-by: George Shuklin <george.shuklin@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/core/rtnetlink.c

@@ -3658,7 +3658,7 @@ static int rtnl_alt_ifname(int cmd, struct net_device *dev, struct nlattr *attr,
 	if (err)
 		return err;
 
-	alt_ifname = nla_strdup(attr, GFP_KERNEL);
+	alt_ifname = nla_strdup(attr, GFP_KERNEL_ACCOUNT);
 	if (!alt_ifname)
 		return -ENOMEM;