1 files changed, 17 insertions, 3 deletions

diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 2aec7c4f357b..2b18053070c1 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -560,6 +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)
@@ -599,7 +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);
@@ -651,7 +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;
@@ -913,6 +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;
@@ -940,7 +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)) {