diff --git a/net/lagg/ieee8023ad_lacp.c b/net/lagg/ieee8023ad_lacp.c
--- a/net/lagg/ieee8023ad_lacp.c
+++ b/net/lagg/ieee8023ad_lacp.c
@@ -307,7 +307,7 @@
 		lacp_dump_lacpdu(du);
 	}
 
-	if ((1 << lp->lp_ifp->if_dunit) & lp->lp_lsc->lsc_debug.lsc_rx_test) {
+	if (((1U << (lp->lp_ifp->if_dunit & 31))) & lp->lp_lsc->lsc_debug.lsc_rx_test) {
 		LACP_TPRINTF((lp, "Dropping RX PDU\n"));
 		goto bad;
 	}