diff --git a/extend/lbson/src/bson.h b/extend/lbson/src/bson.h
index 4e0ca7bf..db4b2b7a 100644
--- a/extend/lbson/src/bson.h
+++ b/extend/lbson/src/bson.h
@@ -137,15 +137,15 @@ namespace lbson {
         }
 
         int binary(lua_State* L) {
+            m_buffer.clean();
             size_t data_len = 0;
             const char* value = lua_tolstring(L, 1, &data_len);
-            luaL_Buffer b;
-            luaL_buffinit(L, &b);
-            luaL_addchar(&b, 0);
-            luaL_addchar(&b, (uint8_t)bson_type::BSON_BINARY);
-            luaL_addchar(&b, 0);
-            luaL_addlstring(&b, value, data_len);
-            luaL_pushresult(&b);
+            m_buffer.write<uint8_t>(0);
+            m_buffer.write<uint8_t>((uint8_t)bson_type::BSON_BINARY);
+            m_buffer.write<uint8_t>(0); //subtype
+            m_buffer.write<int32_t>(data_len);
+            m_buffer.push_data((uint8_t*)value, data_len);
+            lua_pushlstring(L, (const char*)m_buffer.head(), m_buffer.size());
             return 1;
         }
 
@@ -545,12 +545,13 @@ namespace lbson {
                     break;
                 case bson_type::BSON_BINARY: {
                         lua_createtable(L, 0, 4);
+                        int32_t len = read_val<int32_t>(L, slice);
                         lua_pushinteger(L, (uint32_t)bt);
                         lua_setfield(L, -2, "__type");
                         lua_pushinteger(L, read_val<uint8_t>(L, slice));
                         lua_setfield(L, -2, "subtype");
-                        const char* s = read_bytes(L, slice, sz);
-                        lua_pushlstring(L, s, sz);
+                        const char* s = read_bytes(L, slice, len);
+                        lua_pushlstring(L, s, len);
                         lua_setfield(L, -2, "binray");
                     }
                     break;
@@ -639,7 +640,7 @@ namespace lbson {
                 m_bson->unpack_dict(L, m_slice, false);
             } catch (const exception& e){
                 lua_settop(L, otop);
-                throw e;
+                throw lua_exception(e.what());
             }
             return lua_gettop(L) - otop;
         }