diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 174040a..9a1f8bb 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -113,20 +113,20 @@
 		struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_local *local = sdata->local;
-	struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
+	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
-	u8 *pos;
-	int ie_len;
+	u8 *pos, ie_len;
+	int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
+		      sizeof(mgmt->u.action.u.mesh_action);
 
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+			    hdr_len +
+			    2 + 37); /* max HWMP IE */
 	if (!skb)
 		return -1;
 	skb_reserve(skb, local->hw.extra_tx_headroom);
-	/* 25 is the size of the common mgmt part (24) plus the size of the
-	 * common action part (1)
-	 */
-	mgmt = (struct ieee80211_mgmt *)
-		skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action));
-	memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action));
+	mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
+	memset(mgmt, 0, hdr_len);
 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 					  IEEE80211_STYPE_ACTION);
 
@@ -240,20 +240,20 @@
 		       struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_local *local = sdata->local;
-	struct sk_buff *skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
+	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
-	u8 *pos;
-	int ie_len;
+	u8 *pos, ie_len;
+	int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) +
+		      sizeof(mgmt->u.action.u.mesh_action);
 
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
+			    hdr_len +
+			    2 + 15 /* PERR IE */);
 	if (!skb)
 		return -1;
 	skb_reserve(skb, local->tx_headroom + local->hw.extra_tx_headroom);
-	/* 25 is the size of the common mgmt part (24) plus the size of the
-	 * common action part (1)
-	 */
-	mgmt = (struct ieee80211_mgmt *)
-		skb_put(skb, 25 + sizeof(mgmt->u.action.u.mesh_action));
-	memset(mgmt, 0, 25 + sizeof(mgmt->u.action.u.mesh_action));
+	mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len);
+	memset(mgmt, 0, hdr_len);
 	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 					  IEEE80211_STYPE_ACTION);