net: core: check dev_valid_name in __dev_alloc_name

We currently only exclude non-sysfs-friendly names via
dev_get_valid_name; there doesn't seem to be a reason to allow such
names when we're called via dev_alloc_name.

This does duplicate the dev_valid_name check in the dev_get_valid_name()
case; we'll fix that shortly.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/dev.c

@@ -1064,6 +1064,9 @@ static int __dev_alloc_name(struct net *net, const char *name, char *buf)
 	unsigned long *inuse;
 	struct net_device *d;
 
+	if (!dev_valid_name(name))
+		return -EINVAL;
+
 	p = strchr(name, '%');
 	if (p) {
 		/*