P2P: Omit P2P Group Info in case of no connected peers

As per P2P specification v1.2: "The P2P Group Info attribute shall be
omitted if there are zero connected P2P Clients."

Do not add the attribute if there are not connected peers.

Signed-hostap: Chaitanya T K <chaitanya.mgit@gmail.com>

src/p2p/p2p_group.c

@@ -399,7 +399,6 @@ static void wifi_display_group_update(struct p2p_group *group)
 
 static struct wpabuf * p2p_group_build_probe_resp_ie(struct p2p_group *group)
 {
-	u8 *group_info;
 	struct wpabuf *p2p_subelems, *ie;
 	struct p2p_group_member *m;
 
@@ -413,14 +412,18 @@ static struct wpabuf * p2p_group_build_probe_resp_ie(struct p2p_group *group)
 	/* P2P Device Info */
 	p2p_buf_add_device_info(p2p_subelems, group->p2p, NULL);
 
-	/* P2P Group Info */
-	group_info = wpabuf_put(p2p_subelems, 0);
-	wpabuf_put_u8(p2p_subelems, P2P_ATTR_GROUP_INFO);
-	wpabuf_put_le16(p2p_subelems, 0); /* Length to be filled */
-	for (m = group->members; m; m = m->next)
-		p2p_client_info(p2p_subelems, m);
-	WPA_PUT_LE16(group_info + 1,
-		     (u8 *) wpabuf_put(p2p_subelems, 0) - group_info - 3);
+	/* P2P Group Info: Only when at least one P2P Client is connected */
+	if (group->members) {
+		u8 *group_info;
+		group_info = wpabuf_put(p2p_subelems, 0);
+		wpabuf_put_u8(p2p_subelems, P2P_ATTR_GROUP_INFO);
+		wpabuf_put_le16(p2p_subelems, 0); /* Length to be filled */
+		for (m = group->members; m; m = m->next)
+			p2p_client_info(p2p_subelems, m);
+		WPA_PUT_LE16(group_info + 1,
+			     (u8 *) wpabuf_put(p2p_subelems, 0) - group_info -
+			     3);
+	}
 
 	ie = p2p_group_encaps_probe_resp(p2p_subelems);
 	wpabuf_free(p2p_subelems);