ieee802154: Fix EUI-64 station address validation.

Refuse to allow setting an EUI-64 group address as an interface
address, as those are not valid station addresses.
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Acked-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

include/linux/ieee802154.h

@@ -225,15 +225,13 @@ static inline bool ieee802154_is_valid_psdu_len(const u8 len)
  * ieee802154_is_valid_psdu_len - check if extended addr is valid
  * @addr: extended addr to check
  */
-static inline bool ieee802154_is_valid_extended_addr(const __le64 addr)
+static inline bool ieee802154_is_valid_extended_unicast_addr(const __le64 addr)
 {
-	/* These EUI-64 addresses are reserved by IEEE. 0xffffffffffffffff
-	 * is used internally as extended to short address broadcast mapping.
-	 * This is currently a workaround because neighbor discovery can't
-	 * deal with short addresses types right now.
+	/* Bail out if the address is all zero, or if the group
+	 * address bit is set.
 	 */
 	return ((addr != cpu_to_le64(0x0000000000000000ULL)) &&
-		(addr != cpu_to_le64(0xffffffffffffffffULL)));
+		!(addr & cpu_to_le64(0x0100000000000000ULL)));
 }
 
 /**

net/mac802154/iface.c

@@ -126,7 +126,7 @@ static int mac802154_wpan_mac_addr(struct net_device *dev, void *p)
 		return -EBUSY;
 
 	ieee802154_be64_to_le64(&extended_addr, addr->sa_data);
-	if (!ieee802154_is_valid_extended_addr(extended_addr))
+	if (!ieee802154_is_valid_extended_unicast_addr(extended_addr))
 		return -EINVAL;
 
 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
@@ -539,7 +539,7 @@ ieee802154_if_add(struct ieee802154_local *local, const char *name,
 	switch (type) {
 	case NL802154_IFTYPE_NODE:
 		ndev->type = ARPHRD_IEEE802154;
-		if (ieee802154_is_valid_extended_addr(extended_addr))
+		if (ieee802154_is_valid_extended_unicast_addr(extended_addr))
 			ieee802154_le64_to_be64(ndev->dev_addr, &extended_addr);
 		else
 			memcpy(ndev->dev_addr, ndev->perm_addr,