1 files changed, 20 insertions, 22 deletions

diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 5bf64d7112b..2b18053070c 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -391,7 +391,6 @@ static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
 			    (mpath->flags & MESH_PATH_SN_VALID)) {
 				if (SN_GT(mpath->sn, orig_sn) ||
 				    (mpath->sn == orig_sn &&
-				     action == MPATH_PREQ &&
 				     new_metric >= mpath->metric)) {
 					process = false;
 					fresh_info = false;
@@ -561,6 +560,14 @@ static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
 }
 
 
+static inline struct sta_info *
+next_hop_deref_protected(struct mesh_path *mpath)
+{
+	return rcu_dereference_protected(mpath->next_hop,
+					 lockdep_is_held(&mpath->state_lock));
+}
+
+
 static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
 				    struct ieee80211_mgmt *mgmt,
 				    u8 *prep_elem, u32 metric)
@@ -600,7 +607,7 @@ static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
 		spin_unlock_bh(&mpath->state_lock);
 		goto fail;
 	}
-	memcpy(next_hop, mpath->next_hop->sta.addr, ETH_ALEN);
+	memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
 	spin_unlock_bh(&mpath->state_lock);
 	--ttl;
 	flags = PREP_IE_FLAGS(prep_elem);
@@ -633,7 +640,6 @@ static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
 	struct mesh_path *mpath;
 	u8 ttl;
 	u8 *ta, *target_addr;
-	u8 target_flags;
 	u32 target_sn;
 	u16 target_rcode;
 
@@ -644,7 +650,6 @@ static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
 		return;
 	}
 	ttl--;
-	target_flags = PERR_IE_TARGET_FLAGS(perr_elem);
 	target_addr = PERR_IE_TARGET_ADDR(perr_elem);
 	target_sn = PERR_IE_TARGET_SN(perr_elem);
 	target_rcode = PERR_IE_TARGET_RCODE(perr_elem);
@@ -654,7 +659,8 @@ static void hwmp_perr_frame_process(struct ieee80211_sub_if_data *sdata,
 	if (mpath) {
 		spin_lock_bh(&mpath->state_lock);
 		if (mpath->flags & MESH_PATH_ACTIVE &&
-		    memcmp(ta, mpath->next_hop->sta.addr, ETH_ALEN) == 0 &&
+		    memcmp(ta, next_hop_deref_protected(mpath)->sta.addr,
+							ETH_ALEN) == 0 &&
 		    (!(mpath->flags & MESH_PATH_SN_VALID) ||
 		    SN_GT(target_sn, mpath->sn))) {
 			mpath->flags &= ~MESH_PATH_ACTIVE;
@@ -675,12 +681,10 @@ static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
 {
 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	struct mesh_path *mpath;
-	u8 *ta;
 	u8 ttl, flags, hopcount;
 	u8 *orig_addr;
 	u32 orig_sn, metric;
 
-	ta = mgmt->sa;
 	ttl = rann->rann_ttl;
 	if (ttl <= 1) {
 		ifmsh->mshstats.dropped_frames_ttl++;
@@ -918,6 +922,7 @@ int mesh_nexthop_lookup(struct sk_buff *skb,
 {
 	struct sk_buff *skb_to_free = NULL;
 	struct mesh_path *mpath;
+	struct sta_info *next_hop;
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 	u8 *target_addr = hdr->addr3;
 	int err = 0;
@@ -945,7 +950,11 @@ int mesh_nexthop_lookup(struct sk_buff *skb,
 			mesh_queue_preq(mpath,
 					PREQ_Q_F_START | PREQ_Q_F_REFRESH);
 		}
-		memcpy(hdr->addr1, mpath->next_hop->sta.addr, ETH_ALEN);
+		next_hop = rcu_dereference(mpath->next_hop);
+		if (next_hop)
+			memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
+		else
+			err = -ENOENT;
 	} else {
 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 		if (!(mpath->flags & MESH_PATH_RESOLVING)) {
@@ -971,20 +980,11 @@ endlookup:
 
 void mesh_path_timer(unsigned long data)
 {
-	struct ieee80211_sub_if_data *sdata;
-	struct mesh_path *mpath;
-
-	rcu_read_lock();
-	mpath = (struct mesh_path *) data;
-	mpath = rcu_dereference(mpath);
-	if (!mpath)
-		goto endmpathtimer;
-	sdata = mpath->sdata;
+	struct mesh_path *mpath = (void *) data;
+	struct ieee80211_sub_if_data *sdata = mpath->sdata;
 
-	if (sdata->local->quiescing) {
-		rcu_read_unlock();
+	if (sdata->local->quiescing)
 		return;
-	}
 
 	spin_lock_bh(&mpath->state_lock);
 	if (mpath->flags & MESH_PATH_RESOLVED ||
@@ -1001,8 +1001,6 @@ void mesh_path_timer(unsigned long data)
 	}
 
 	spin_unlock_bh(&mpath->state_lock);
-endmpathtimer:
-	rcu_read_unlock();
 }
 
 void