p2p: possibly fix crash in relay_blocks

src/cryptonote_protocol/cryptonote_protocol_handler.inl

@@ -1093,20 +1093,35 @@ namespace cryptonote
     fluffy_arg.b = arg.b;
     fluffy_arg.b.txs = fluffy_txs;
 
-    m_p2p->for_each_connection([this, &arg, &fluffy_arg](connection_context& cntxt, nodetool::peerid_type peer_id, uint32_t support_flags)
+    // pre-serialize them
+    std::string fullBlob, fluffyBlob;
+    epee::serialization::store_t_to_binary(arg, fullBlob);
+    epee::serialization::store_t_to_binary(fluffy_arg, fluffyBlob);
+
+    // sort peers between fluffy ones and others
+    std::list<boost::uuids::uuid> fullConnections, fluffyConnections;
+    m_p2p->for_each_connection([this, &arg, &fluffy_arg, &exclude_context, &fullConnections, &fluffyConnections](connection_context& context, nodetool::peerid_type peer_id, uint32_t support_flags)
     {
-      if(m_core.get_testnet() && support_flags & P2P_SUPPORT_FLAG_FLUFFY_BLOCKS)
+      if (peer_id && exclude_context.m_connection_id != context.m_connection_id)
       {
-        LOG_PRINT_YELLOW("PEER SUPPORTS FLUFFY BLOCKS - RELAYING THIN/COMPACT WHATEVER BLOCK", LOG_LEVEL_1);
+        if(m_core.get_testnet() && (support_flags & P2P_SUPPORT_FLAG_FLUFFY_BLOCKS))
-        return post_notify<NOTIFY_NEW_FLUFFY_BLOCK>(fluffy_arg, cntxt);
+        {
+          LOG_PRINT_CCONTEXT_YELLOW("PEER SUPPORTS FLUFFY BLOCKS - RELAYING THIN/COMPACT WHATEVER BLOCK", LOG_LEVEL_1);
+          fluffyConnections.push_back(context.m_connection_id);
         }
         else
         {
-        LOG_PRINT_YELLOW("PEER DOESN'T SUPPORT FLUFFY BLOCKS - RELAYING FULL BLOCK", LOG_LEVEL_1);
+          LOG_PRINT_CCONTEXT_YELLOW("PEER DOESN'T SUPPORT FLUFFY BLOCKS - RELAYING FULL BLOCK", LOG_LEVEL_1);
-        return post_notify<NOTIFY_NEW_BLOCK>(arg, cntxt);
+          fullConnections.push_back(context.m_connection_id);
         }
+      }
+      return true;
     });
 
+    // send fluffy ones first, we want to encourage people to run that
+    m_p2p->relay_notify_to_list(NOTIFY_NEW_FLUFFY_BLOCK::ID, fluffyBlob, fluffyConnections);
+    m_p2p->relay_notify_to_list(NOTIFY_NEW_BLOCK::ID, fullBlob, fullConnections);
+
     return 1;
   }
   //------------------------------------------------------------------------------------------------------------------------

src/p2p/net_node.h

@@ -172,6 +172,7 @@ namespace nodetool
     virtual void on_connection_close(p2p_connection_context& context);
     virtual void callback(p2p_connection_context& context);
     //----------------- i_p2p_endpoint -------------------------------------------------------------
+    virtual bool relay_notify_to_list(int command, const std::string& data_buff, const std::list<boost::uuids::uuid> &connections);
     virtual bool relay_notify_to_all(int command, const std::string& data_buff, const epee::net_utils::connection_context_base& context);
     virtual bool invoke_command_to_peer(int command, const std::string& req_buff, std::string& resp_buff, const epee::net_utils::connection_context_base& context);
     virtual bool invoke_notify_to_peer(int command, const std::string& req_buff, const epee::net_utils::connection_context_base& context);

src/p2p/net_node.inl

@@ -1242,6 +1242,16 @@ namespace nodetool
   }
   //-----------------------------------------------------------------------------------
   template<class t_payload_net_handler>
+  bool node_server<t_payload_net_handler>::relay_notify_to_list(int command, const std::string& data_buff, const std::list<boost::uuids::uuid> &connections)
+  {
+    BOOST_FOREACH(const auto& c_id, connections)
+    {
+      m_net_server.get_config_object().notify(command, data_buff, c_id);
+    }
+    return true;
+  }
+  //-----------------------------------------------------------------------------------
+  template<class t_payload_net_handler>
   bool node_server<t_payload_net_handler>::relay_notify_to_all(int command, const std::string& data_buff, const epee::net_utils::connection_context_base& context)
   {
     std::list<boost::uuids::uuid> connections;
@@ -1251,12 +1261,7 @@ namespace nodetool
         connections.push_back(cntxt.m_connection_id);
       return true;
     });
-
+    return relay_notify_to_list(command, data_buff, connections);
-    BOOST_FOREACH(const auto& c_id, connections)
-    {
-      m_net_server.get_config_object().notify(command, data_buff, c_id);
-    }
-    return true;
   }
   //-----------------------------------------------------------------------------------
   template<class t_payload_net_handler>

src/p2p/net_node_common.h

@@ -43,6 +43,7 @@ namespace nodetool
   template<class t_connection_context>
   struct i_p2p_endpoint
   {
+    virtual bool relay_notify_to_list(int command, const std::string& data_buff, const std::list<boost::uuids::uuid>& connections)=0;
     virtual bool relay_notify_to_all(int command, const std::string& data_buff, const epee::net_utils::connection_context_base& context)=0;
     virtual bool invoke_command_to_peer(int command, const std::string& req_buff, std::string& resp_buff, const epee::net_utils::connection_context_base& context)=0;
     virtual bool invoke_notify_to_peer(int command, const std::string& req_buff, const epee::net_utils::connection_context_base& context)=0;
@@ -59,6 +60,10 @@ namespace nodetool
   template<class t_connection_context>
   struct p2p_endpoint_stub: public i_p2p_endpoint<t_connection_context>
   {
+    virtual bool relay_notify_to_list(int command, const std::string& data_buff, const std::list<boost::uuids::uuid>& connections)
+    {
+      return false;
+    }
     virtual bool relay_notify_to_all(int command, const std::string& data_buff, const epee::net_utils::connection_context_base& context)
     {
       return false;