Merge tag 'linux-can-fixes-for-5.9-20200815' of...

Merge tag 'linux-can-fixes-for-5.9-20200815' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2020-08-15

this is a pull request of 4 patches for net/master.

All patches are by Zhang Changzhong and fix broadcast related problems in the
j1939 CAN networking stack.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/can/j1939/transport.c

@@ -723,10 +723,12 @@ static int j1939_session_tx_rts(struct j1939_session *session)
 		return ret;
 
 	session->last_txcmd = dat[0];
-	if (dat[0] == J1939_TP_CMD_BAM)
+	if (dat[0] == J1939_TP_CMD_BAM) {
 		j1939_tp_schedule_txtimer(session, 50);
-
-	j1939_tp_set_rxtimeout(session, 1250);
+		j1939_tp_set_rxtimeout(session, 250);
+	} else {
+		j1939_tp_set_rxtimeout(session, 1250);
+	}
 
 	netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session);
 
@@ -1074,9 +1076,9 @@ static void __j1939_session_cancel(struct j1939_session *session,
 	lockdep_assert_held(&session->priv->active_session_list_lock);
 
 	session->err = j1939_xtp_abort_to_errno(priv, err);
+	session->state = J1939_SESSION_WAITING_ABORT;
 	/* do not send aborts on incoming broadcasts */
 	if (!j1939_cb_is_broadcast(&session->skcb)) {
-		session->state = J1939_SESSION_WAITING_ABORT;
 		j1939_xtp_tx_abort(priv, &session->skcb,
 				   !session->transmission,
 				   err, session->skcb.addr.pgn);
@@ -1673,8 +1675,12 @@ static void j1939_xtp_rx_rts(struct j1939_priv *priv, struct sk_buff *skb,
 			return;
 		}
 		session = j1939_xtp_rx_rts_session_new(priv, skb);
-		if (!session)
+		if (!session) {
+			if (cmd == J1939_TP_CMD_BAM && j1939_sk_recv_match(priv, skcb))
+				netdev_info(priv->ndev, "%s: failed to create TP BAM session\n",
+					    __func__);
 			return;
+		}
 	} else {
 		if (j1939_xtp_rx_rts_session_active(session, skb)) {
 			j1939_session_put(session);
@@ -1683,11 +1689,15 @@ static void j1939_xtp_rx_rts(struct j1939_priv *priv, struct sk_buff *skb,
 	}
 	session->last_cmd = cmd;
 
-	j1939_tp_set_rxtimeout(session, 1250);
-
-	if (cmd != J1939_TP_CMD_BAM && !session->transmission) {
-		j1939_session_txtimer_cancel(session);
-		j1939_tp_schedule_txtimer(session, 0);
+	if (cmd == J1939_TP_CMD_BAM) {
+		if (!session->transmission)
+			j1939_tp_set_rxtimeout(session, 750);
+	} else {
+		if (!session->transmission) {
+			j1939_session_txtimer_cancel(session);
+			j1939_tp_schedule_txtimer(session, 0);
+		}
+		j1939_tp_set_rxtimeout(session, 1250);
 	}
 
 	j1939_session_put(session);
@@ -1738,6 +1748,7 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
 	int offset;
 	int nbytes;
 	bool final = false;
+	bool remain = false;
 	bool do_cts_eoma = false;
 	int packet;
 
@@ -1813,6 +1824,8 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
 	    j1939_cb_is_broadcast(&session->skcb)) {
 		if (session->pkt.rx >= session->pkt.total)
 			final = true;
+		else
+			remain = true;
 	} else {
 		/* never final, an EOMA must follow */
 		if (session->pkt.rx >= session->pkt.last)
@@ -1820,7 +1833,11 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
 	}
 
 	if (final) {
+		j1939_session_timers_cancel(session);
 		j1939_session_completed(session);
+	} else if (remain) {
+		if (!session->transmission)
+			j1939_tp_set_rxtimeout(session, 750);
 	} else if (do_cts_eoma) {
 		j1939_tp_set_rxtimeout(session, 1250);
 		if (!session->transmission)
@@ -1865,6 +1882,13 @@ static void j1939_xtp_rx_dat(struct j1939_priv *priv, struct sk_buff *skb)
 		else
 			j1939_xtp_rx_dat_one(session, skb);
 	}
+
+	if (j1939_cb_is_broadcast(skcb)) {
+		session = j1939_session_get_by_addr(priv, &skcb->addr, false,
+						    false);
+		if (session)
+			j1939_xtp_rx_dat_one(session, skb);
+	}
 }
 
 /* j1939 main intf */
@@ -1956,7 +1980,7 @@ static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb)
 		if (j1939_tp_im_transmitter(skcb))
 			j1939_xtp_rx_rts(priv, skb, true);
 
-		if (j1939_tp_im_receiver(skcb))
+		if (j1939_tp_im_receiver(skcb) || j1939_cb_is_broadcast(skcb))
 			j1939_xtp_rx_rts(priv, skb, false);
 
 		break;
@@ -2020,7 +2044,7 @@ int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb)
 {
 	struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb);
 
-	if (!j1939_tp_im_involved_anydir(skcb))
+	if (!j1939_tp_im_involved_anydir(skcb) && !j1939_cb_is_broadcast(skcb))
 		return 0;
 
 	switch (skcb->addr.pgn) {