Index: lib/libc/gen/arc4random.c
===================================================================
--- lib/libc/gen/arc4random.c	(revision 243718)
+++ lib/libc/gen/arc4random.c	(working copy)
@@ -249,12 +249,14 @@ arc4random_buf(void *_buf, size_t n)
 {
 	u_char *buf = (u_char *)_buf;
 	_ARC4_LOCK();
+	arc4_count -= n % 1600000;
 	arc4_stir_if_needed();
-	while (n--) {
-		if (--arc4_count <= 0)
-			arc4_stir();
-		buf[n] = arc4_getbyte();
-	}
+	if (arc4_sysctl(_buf, n) != n)
+		while (n--) {
+			if (--arc4_count <= 0)
+				arc4_stir();
+			buf[n] = arc4_getbyte();
+		}
 	_ARC4_UNLOCK();
 }