Index: sys/compat/linux/linux_misc.c
===================================================================
--- sys/compat/linux/linux_misc.c
+++ sys/compat/linux/linux_misc.c
@@ -1090,6 +1090,10 @@
 	idtype_t idtype;
 	int error, options;
 
+	if (args->options & ~(LINUX_WNOHANG | LINUX_WNOWAIT | LINUX_WEXITED |
+	    LINUX_WSTOPPED | LINUX_WCONTINUED | __WCLONE | __WNOTHREAD | __WALL))
+		return (EINVAL);
+
 	options = 0;
 	linux_to_bsd_waitopts(args->options, &options);