ZD1211RW unaligned accesses...

[David Miller <davem@davemloft.net>]

The problem is drivers/net/wireless/zd1211/zd_mac.c:update_qual_rssi().
Specifically the compare_ether_addr() call.  Now, ieee80211_hdr_3addr
is marked with attribute((unaligned)) but compare_ether_addr() does
not know that and does "u16 *" dereferences in the optimized
comparison.

Shaddy I attach a hack patch that you can use which should get
rid of the warnings.

Wireless folks, I would suggest we do some auditing of the
compare_ether_addr() calls and for the ones that are operating
on these potentially unaligned structs we change it to either
a straight memcmp() or some new routine which will more reflect
the issue (say something like "compare_ether_addr_unaligned()"
or "ieee80211_compare_ether_addr()").

diff --git a/drivers/net/wireless/zd1211rw/zd_mac.c b/drivers/net/wireless/zd1211rw/zd_mac.c
index a903645..4999869 100644
--- a/drivers/net/wireless/zd1211rw/zd_mac.c
+++ b/drivers/net/wireless/zd1211rw/zd_mac.c
@@ -1047,8 +1047,13 @@ static void update_qual_rssi(struct zd_mac *mac,
 	hdr = (struct ieee80211_hdr_3addr *)buffer;
 	if (length < offsetof(struct ieee80211_hdr_3addr, addr3))
 		return;
+#if 1
+	if (memcmp(hdr->addr2, zd_mac_to_ieee80211(mac)->bssid, ETH_ALEN))
+		return;
+#else
 	if (compare_ether_addr(hdr->addr2, zd_mac_to_ieee80211(mac)->bssid) != 0)
 		return;
+#endif
 
 	spin_lock_irqsave(&mac->lock, flags);
 	i = mac->stats_count % ZD_MAC_STATS_BUFFER_SIZE;