--- uwsgi-1.3/plugins/lua/lua_plugin.c
+++ uwsgi-1.3.alpine/plugins/lua/lua_plugin.c
@@ -306,6 +306,8 @@
 static int uwsgi_lua_input(lua_State *L) {
 
 	struct wsgi_request *wsgi_req = current_wsgi_req();
+	int fd = wsgi_req->async_post ?
+	  fileno(wsgi_req->async_post) : wsgi_req->poll.fd;
 	ssize_t sum, len, total;
 	char *buf, *ptr;
 
@@ -328,7 +330,7 @@
 
 	ptr = buf;
 	while(total) {
-		len = read(wsgi_req->poll.fd, ptr, total);
+		len = read(fd, ptr, total);
 		ptr += len;
 		total -= len;
 	}