[PATCH net-next 07/15] batman-adv: ensure u16 aligned mac address in structs

[Simon Wunderlich <sw@simonwunderlich.de>]

From: Sven Eckelmann <sven@narfation.org>

An u8 array in structures have a natural alignment of only 1 byte. An
u8[ETH_ALEN] array must therefore be assumed to only be 1 byte aligned. But
many etherdevices.h functions are requiring a 2 byte (u16) alignment.

All these addresses were either on the start of a struct or after a struct
member which required at least an alignment of 2 byte. Still, annote all
u8[ETH_ALEN] arrays on the stack as __aligned(2) to make sure that this
assumption isn't broken by other modifications inside the structs.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/types.h | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 99667f632d4d9..c42a4aa8f41a3 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -410,7 +410,7 @@ struct batadv_orig_bat_iv {
  */
 struct batadv_orig_node {
 	/** @orig: originator ethernet address */
-	u8 orig[ETH_ALEN];
+	u8 orig[ETH_ALEN] __aligned(2);
 
 	/** @ifinfo_list: list for routers per outgoing interface */
 	struct hlist_head ifinfo_list;
@@ -634,12 +634,12 @@ struct batadv_hardif_neigh_node {
 	struct hlist_node list;
 
 	/** @addr: the MAC address of the neighboring interface */
-	u8 addr[ETH_ALEN];
+	u8 addr[ETH_ALEN] __aligned(2);
 
 	/**
 	 * @orig: the address of the originator this neighbor node belongs to
 	 */
-	u8 orig[ETH_ALEN];
+	u8 orig[ETH_ALEN] __aligned(2);
 
 	/** @if_incoming: pointer to incoming hard-interface */
 	struct batadv_hard_iface *if_incoming;
@@ -677,7 +677,7 @@ struct batadv_neigh_node {
 #endif
 
 	/** @addr: the MAC address of the neighboring interface */
-	u8 addr[ETH_ALEN];
+	u8 addr[ETH_ALEN] __aligned(2);
 
 	/** @ifinfo_list: list for routing metrics per outgoing interface */
 	struct hlist_head ifinfo_list;
@@ -777,7 +777,7 @@ struct batadv_neigh_ifinfo {
  */
 struct batadv_bcast_duplist_entry {
 	/** @orig: mac address of orig node originating the broadcast */
-	u8 orig[ETH_ALEN];
+	u8 orig[ETH_ALEN] __aligned(2);
 
 	/** @crc: crc32 checksum of broadcast payload */
 	u32 crc;
@@ -1085,7 +1085,7 @@ struct batadv_priv_bla {
 	struct batadv_hashtable *backbone_hash;
 
 	/** @loopdetect_addr: MAC address used for own loopdetection frames */
-	u8 loopdetect_addr[ETH_ALEN];
+	u8 loopdetect_addr[ETH_ALEN] __aligned(2);
 
 	/**
 	 * @loopdetect_lasttime: time when the loopdetection frames were sent
@@ -1352,7 +1352,7 @@ struct batadv_tp_vars_common {
 	struct batadv_priv *bat_priv;
 
 	/** @other_end: mac address of remote */
-	u8 other_end[ETH_ALEN];
+	u8 other_end[ETH_ALEN] __aligned(2);
 
 	/** @session: TP session identifier */
 	u8 session[2];
@@ -1765,7 +1765,7 @@ struct batadv_bla_backbone_gw {
 	 * @orig: originator address of backbone node (mac address of primary
 	 *  iface)
 	 */
-	u8 orig[ETH_ALEN];
+	u8 orig[ETH_ALEN] __aligned(2);
 
 	/** @vid: vlan id this gateway was detected on */
 	unsigned short vid;
@@ -1810,7 +1810,7 @@ struct batadv_bla_backbone_gw {
  */
 struct batadv_bla_claim {
 	/** @addr: mac address of claimed non-mesh client */
-	u8 addr[ETH_ALEN];
+	u8 addr[ETH_ALEN] __aligned(2);
 
 	/** @vid: vlan id this client was detected on */
 	unsigned short vid;
@@ -1840,7 +1840,7 @@ struct batadv_bla_claim {
  */
 struct batadv_tt_common_entry {
 	/** @addr: mac address of non-mesh client */
-	u8 addr[ETH_ALEN];
+	u8 addr[ETH_ALEN] __aligned(2);
 
 	/** @vid: VLAN identifier */
 	unsigned short vid;
@@ -1942,7 +1942,7 @@ struct batadv_tt_req_node {
 	/**
 	 * @addr: mac address of the originator this request was sent to
 	 */
-	u8 addr[ETH_ALEN];
+	u8 addr[ETH_ALEN] __aligned(2);
 
 	/** @issued_at: timestamp used for purging stale tt requests */
 	unsigned long issued_at;
@@ -1959,7 +1959,7 @@ struct batadv_tt_req_node {
  */
 struct batadv_tt_roam_node {
 	/** @addr: mac address of the client in the roaming phase */
-	u8 addr[ETH_ALEN];
+	u8 addr[ETH_ALEN] __aligned(2);
 
 	/** @vid: VLAN identifier */
 	u16 vid;
@@ -2204,7 +2204,7 @@ struct batadv_hw_addr {
 	struct hlist_node list;
 
 	/** @addr: the MAC address of this list entry */
-	unsigned char addr[ETH_ALEN];
+	unsigned char addr[ETH_ALEN] __aligned(2);
 };
 
 /**
-- 
2.47.3