diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat.c b/openbsc/src/osmo-bsc_nat/bsc_nat.c
index 1fc262d..c70153f 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat.c
@@ -1024,7 +1024,7 @@
 
 	if (vec.res_len != 8) {
 		LOGP(DNAT, LOGL_ERROR, "Res length is wrong: %d for bsc nr %d\n",
-			keylen, conf->nr);
+			vec.res_len, conf->nr);
 		return 0;
 	}