4 files changed, 42 insertions, 51 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 6e43feb49a76..edca2a288abd 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1540,7 +1540,6 @@ static int ieee80211_add_mpath(struct wiphy *wiphy, struct net_device *dev,
         struct ieee80211_sub_if_data *sdata;
         struct mesh_path *mpath;
         struct sta_info *sta;
-        int err;
 
         sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 
@@ -1551,17 +1550,12 @@ static int ieee80211_add_mpath(struct wiphy *wiphy, struct net_device *dev,
                 return -ENOENT;
         }
 
-        err = mesh_path_add(sdata, dst);
-        if (err) {
+        mpath = mesh_path_add(sdata, dst);
+        if (IS_ERR(mpath)) {
                 rcu_read_unlock();
-                return err;
+                return PTR_ERR(mpath);
         }
 
-        mpath = mesh_path_lookup(sdata, dst);
-        if (!mpath) {
-                rcu_read_unlock();
-                return -ENXIO;
-        }
         mesh_path_fix_nexthop(mpath, sta);
 
         rcu_read_unlock();
diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h
index 6ffabbe99c46..da158774eebb 100644
--- a/net/mac80211/mesh.h
+++ b/net/mac80211/mesh.h
@@ -275,7 +275,8 @@ void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop);
 void mesh_path_expire(struct ieee80211_sub_if_data *sdata);
 void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
                             struct ieee80211_mgmt *mgmt, size_t len);
-int mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
+struct mesh_path *
+mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst);
 
 int mesh_path_add_gate(struct mesh_path *mpath);
 int mesh_path_send_to_gates(struct mesh_path *mpath);
diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 94904337784c..c82d5e6a24c0 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -445,9 +445,8 @@ static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
                                 }
                         }
                 } else {
-                        mesh_path_add(sdata, orig_addr);
-                        mpath = mesh_path_lookup(sdata, orig_addr);
-                        if (!mpath) {
+                        mpath = mesh_path_add(sdata, orig_addr);
+                        if (IS_ERR(mpath)) {
                                 rcu_read_unlock();
                                 return 0;
                         }
@@ -486,9 +485,8 @@ static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata,
                                         (last_hop_metric > mpath->metric)))
                                 fresh_info = false;
                 } else {
-                        mesh_path_add(sdata, ta);
-                        mpath = mesh_path_lookup(sdata, ta);
-                        if (!mpath) {
+                        mpath = mesh_path_add(sdata, ta);
+                        if (IS_ERR(mpath)) {
                                 rcu_read_unlock();
                                 return 0;
                         }
@@ -804,9 +802,8 @@ static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
 
         mpath = mesh_path_lookup(sdata, orig_addr);
         if (!mpath) {
-                mesh_path_add(sdata, orig_addr);
-                mpath = mesh_path_lookup(sdata, orig_addr);
-                if (!mpath) {
+                mpath = mesh_path_add(sdata, orig_addr);
+                if (IS_ERR(mpath)) {
                         rcu_read_unlock();
                         sdata->u.mesh.mshstats.dropped_frames_no_route++;
                         return;
@@ -1098,11 +1095,10 @@ int mesh_nexthop_resolve(struct ieee80211_sub_if_data *sdata,
         /* no nexthop found, start resolving */
         mpath = mesh_path_lookup(sdata, target_addr);
         if (!mpath) {
-                mesh_path_add(sdata, target_addr);
-                mpath = mesh_path_lookup(sdata, target_addr);
-                if (!mpath) {
+                mpath = mesh_path_add(sdata, target_addr);
+                if (IS_ERR(mpath)) {
                         mesh_path_discard_frame(sdata, skb);
-                        err = -ENOSPC;
+                        err = PTR_ERR(mpath);
                         goto endlookup;
                 }
         }
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index dc7c8df40c2c..89aacfd2756d 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -493,7 +493,8 @@ int mesh_gate_num(struct ieee80211_sub_if_data *sdata)
  *
  * State: the initial state of the new path is set to 0
  */
-int mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst)
+struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata,
+                                const u8 *dst)
 {
         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
         struct ieee80211_local *local = sdata->local;
@@ -502,18 +503,33 @@ int mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst)
         struct mpath_node *node, *new_node;
         struct hlist_head *bucket;
         int grow = 0;
-        int err = 0;
+        int err;
         u32 hash_idx;
 
         if (ether_addr_equal(dst, sdata->vif.addr))
                 /* never add ourselves as neighbours */
-                return -ENOTSUPP;
+                return ERR_PTR(-ENOTSUPP);
 
         if (is_multicast_ether_addr(dst))
-                return -ENOTSUPP;
+                return ERR_PTR(-ENOTSUPP);
 
         if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
-                return -ENOSPC;
+                return ERR_PTR(-ENOSPC);
+
+        read_lock_bh(&pathtbl_resize_lock);
+        tbl = resize_dereference_mesh_paths();
+
+        hash_idx = mesh_table_hash(dst, sdata, tbl);
+        bucket = &tbl->hash_buckets[hash_idx];
+
+        spin_lock(&tbl->hashwlock[hash_idx]);
+
+        hlist_for_each_entry(node, bucket, list) {
+                mpath = node->mpath;
+                if (mpath->sdata == sdata &&
+                    ether_addr_equal(dst, mpath->dst))
+                        goto found;
+        }
 
         err = -ENOMEM;
         new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
@@ -524,7 +540,6 @@ int mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst)
         if (!new_node)
                 goto err_node_alloc;
 
-        read_lock_bh(&pathtbl_resize_lock);
         memcpy(new_mpath->dst, dst, ETH_ALEN);
         eth_broadcast_addr(new_mpath->rann_snd_addr);
         new_mpath->is_root = false;
@@ -538,21 +553,6 @@ int mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst)
         spin_lock_init(&new_mpath->state_lock);
         init_timer(&new_mpath->timer);
 
-        tbl = resize_dereference_mesh_paths();
-
-        hash_idx = mesh_table_hash(dst, sdata, tbl);
-        bucket = &tbl->hash_buckets[hash_idx];
-
-        spin_lock(&tbl->hashwlock[hash_idx]);
-
-        err = -EEXIST;
-        hlist_for_each_entry(node, bucket, list) {
-                mpath = node->mpath;
-                if (mpath->sdata == sdata &&
-                    ether_addr_equal(dst, mpath->dst))
-                        goto err_exists;
-        }
-
         hlist_add_head_rcu(&new_node->list, bucket);
         if (atomic_inc_return(&tbl->entries) >=
             tbl->mean_chain_len * (tbl->hash_mask + 1))
@@ -560,23 +560,23 @@ int mesh_path_add(struct ieee80211_sub_if_data *sdata, const u8 *dst)
 
         mesh_paths_generation++;
 
-        spin_unlock(&tbl->hashwlock[hash_idx]);
-        read_unlock_bh(&pathtbl_resize_lock);
         if (grow) {
                 set_bit(MESH_WORK_GROW_MPATH_TABLE,  &ifmsh->wrkq_flags);
                 ieee80211_queue_work(&local->hw, &sdata->work);
         }
-        return 0;
-
-err_exists:
+        mpath = new_mpath;
+found:
         spin_unlock(&tbl->hashwlock[hash_idx]);
         read_unlock_bh(&pathtbl_resize_lock);
-        kfree(new_node);
+        return mpath;
+
 err_node_alloc:
         kfree(new_mpath);
 err_path_alloc:
         atomic_dec(&sdata->u.mesh.mpaths);
-        return err;
+        spin_unlock(&tbl->hashwlock[hash_idx]);
+        read_unlock_bh(&pathtbl_resize_lock);
+        return ERR_PTR(err);
 }
 
 static void mesh_table_free_rcu(struct rcu_head *rcu)