Handle ps-poll data frame if_transmit() failure.

If the data frame transmission failures, it may have a node reference
that needs cleaning up.

If the frame is marked as M_ENCAP then it should treat recvif as a node
reference and clear it.

Now - since the mbuf has been freed by calling if_transmit() (even on
failure), the mbuf has to be treated as invalid.  Hence why the ifp is
used.

1 files changed, 15 insertions, 1 deletions

diff --git a/sys/net80211/ieee80211_hostap.c b/sys/net80211/ieee80211_hostap.c
index 675f3da..7087748 100644
--- a/sys/net80211/ieee80211_hostap.c
+++ b/sys/net80211/ieee80211_hostap.c
@@ -2324,5 +2324,19 @@ ieee80211_recv_pspoll(struct ieee80211_node *ni, struct mbuf *m0)
 		ifp = vap->iv_ic->ic_ifp;
 	else
 		ifp = vap->iv_ifp;
-	(void) ifp->if_transmit(ifp, m);
+
+	/*
+	 * Free any node ref which this mbuf may have.
+	 *
+	 * Much like psq_mfree(), we assume that M_ENCAP nodes have
+	 * node references.
+	 */
+	if (ifp->if_transmit(ifp, m) != 0) {
+		/*
+		 * XXX m is invalid (freed) at this point, determine M_ENCAP
+		 * an alternate way.
+		 */
+		if (ifp == vap->iv_ic->ic_ifp)
+			ieee80211_free_node(ni);
+	}
 }