mac80211: fix PREQ processing and one small bug

1st) a PREQ should only be processed, if it has the same SN and better
metric (instead of better or equal).
2nd) next_hop[ETH_ALEN] now actually used to buffer
mpath->next_hop->sta.addr for use out of lock.
Signed-off-by: Marco Porsch <marco.porsch@siemens.com>
Acked-by: Javier Cardona <javier@cozybit.com>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/mesh_hwmp.c

@@ -391,7 +391,7 @@ static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
 				if (SN_GT(mpath->sn, orig_sn) ||
 				    (mpath->sn == orig_sn &&
 				     action == MPATH_PREQ &&
-				     new_metric > mpath->metric)) {
+				     new_metric >= mpath->metric)) {
 					process = false;
 					fresh_info = false;
 				}
@@ -611,7 +611,7 @@ static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
 
 	mesh_path_sel_frame_tx(MPATH_PREP, flags, orig_addr,
 		cpu_to_le32(orig_sn), 0, target_addr,
-		cpu_to_le32(target_sn), mpath->next_hop->sta.addr, hopcount,
+		cpu_to_le32(target_sn), next_hop, hopcount,
 		ttl, cpu_to_le32(lifetime), cpu_to_le32(metric),
 		0, sdata);
 	rcu_read_unlock();