diff --git a/include/linux/signal.h b/include/linux/signal.h
index 78bfb26..0a98f5e 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -220,6 +220,12 @@
 	INIT_LIST_HEAD(&sig->list);
 }
 
+/* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
+static inline int valid_signal(unsigned long sig)
+{
+	return sig <= _NSIG ? 1 : 0;
+}
+
 extern int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p);
 extern int __group_send_sig_info(int, struct siginfo *, struct task_struct *);
 extern long do_sigpending(void __user *, unsigned long);