diff --git a/include/net/netfilter/xt_log.h b/include/net/netfilter/xt_log.h
index 0dfb34a..7e1544e 100644
--- a/include/net/netfilter/xt_log.h
+++ b/include/net/netfilter/xt_log.h
@@ -6,7 +6,7 @@ struct sbuff {
 };
 static struct sbuff emergency, *emergency_ptr = &emergency;
 
-static int sb_add(struct sbuff *m, const char *f, ...)
+static __printf(2, 3) int sb_add(struct sbuff *m, const char *f, ...)
 {
 	va_list args;
 	int len;