module/script: close all unrelated FDs

While most FDs are CLOEXEC, not all are. For example, other script
modules’ re-direction pipes.

modules/script.c

@@ -479,6 +479,16 @@ run(struct module *mod)
         close(comm_pipe[1]);
         comm_pipe[1] = -1;
 
+        /* Close *all* other FDs */
+        for (int i = STDERR_FILENO + 1; i < 65536; i++) {
+            if (i == exec_pipe[1]) {
+                /* Needed for error reporting. Automatically closed
+                 * when execvp() succeeds */
+                continue;
+            }
+            close(i);
+        }
+
         execvp(m->path, argv);
 
     fail: