--- a/ath/if_ath.c
+++ b/ath/if_ath.c
@@ -3697,6 +3697,7 @@ ff_bypass:
 	 */
 	skb = ieee80211_encap(ni, skb, &framecnt);
 	if (skb == NULL) {
+		STAILQ_INSERT_TAIL(&bf_head, bf, bf_list);
 		DPRINTF(sc, ATH_DEBUG_XMIT,
 			"Dropping; encapsulation failure\n");
 		sc->sc_stats.ast_tx_encap++;