diff --git a/usr.sbin/arp/arp.c b/usr.sbin/arp/arp.c
index 5a22ea844e1..0a099af0744 100644
--- a/usr.sbin/arp/arp.c
+++ b/usr.sbin/arp/arp.c
@@ -384,7 +384,7 @@ set(int argc, char **argv)
 	}
 	sdl_m.sdl_type = sdl->sdl_type;
 	sdl_m.sdl_index = sdl->sdl_index;
-	return (rtmsg(RTM_ADD, dst, &sdl_m) != NULL);
+	return (rtmsg(RTM_ADD, dst, &sdl_m) == NULL);
 }
 
 /*