diff --git a/lualib-src/lua-socket.c b/lualib-src/lua-socket.c
index 38f96a5c..b7fc69ec 100644
--- a/lualib-src/lua-socket.c
+++ b/lualib-src/lua-socket.c
@@ -537,7 +537,7 @@ get_buffer(lua_State *L, int index, struct socket_sendbuffer *buf) {
 		if (lua_isinteger(L, index+1)) {
 			buf->sz = lua_tointeger(L, index+1);
 		} else {
-			buf->sz = lua_rawlen(L, index+1);
+			buf->sz = lua_rawlen(L, index);
 		}
 		break;
 	case LUA_TLIGHTUSERDATA: {
diff --git a/skynet-src/socket_server.c b/skynet-src/socket_server.c
index 1ebaa0bd..0e1fbd13 100644
--- a/skynet-src/socket_server.c
+++ b/skynet-src/socket_server.c
@@ -58,7 +58,7 @@
 
 #define WARNING_SIZE (1024*1024)
 
-#define USEROBJECT ((size_t)(~0))
+#define USEROBJECT ((size_t)(-1))
 
 struct write_buffer {
 	struct write_buffer * next;