pull-request: can 2020-08-15

Hello David,

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.

regards,
Marc

---

The following changes since commit 4ca0d9ac3fd8f9f90b72a15d8da2aca3ffb58418:

  bonding: show saner speed for broadcast mode (2020-08-14 20:39:33 -0700)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can.git tags/linux-can-fixes-for-5.9-20200815

for you to fetch changes up to 0ae18a82686f9b9965a8ce0dd81371871b306ffe:

  can: j1939: add rxtimer for multipacket broadcast session (2020-08-15 11:12:58 +0200)

----------------------------------------------------------------
linux-can-fixes-for-5.9-20200815

----------------------------------------------------------------
Zhang Changzhong (4):
      can: j1939: fix support for multipacket broadcast message
      can: j1939: cancel rxtimer on multipacket broadcast session complete
      can: j1939: abort multipacket broadcast session when timeout occurs
      can: j1939: add rxtimer for multipacket broadcast session

 net/can/j1939/transport.c | 48 +++++++++++++++++++++++++++++++++++------------
 1 file changed, 36 insertions(+), 12 deletions(-)

From: Zhang Changzhong <redacted>

If timeout occurs, j1939_tp_rxtimer() first calls hrtimer_start() to restart
rxtimer, and then calls __j1939_session_cancel() to set session->state =
J1939_SESSION_WAITING_ABORT. At next timeout expiration, because of the
J1939_SESSION_WAITING_ABORT session state j1939_tp_rxtimer() will call
j1939_session_deactivate_activate_next() to deactivate current session, and
rxtimer won't be set.

But for multipacket broadcast session, __j1939_session_cancel() don't set
session->state = J1939_SESSION_WAITING_ABORT, thus current session won't be
deactivate and hrtimer_start() is called to start new rxtimer again and again.

So fix it by moving session->state = J1939_SESSION_WAITING_ABORT out of if
(!j1939_cb_is_broadcast(&session->skcb)) statement.

Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Signed-off-by: Zhang Changzhong <redacted>
Link: https://lore.kernel.org/r/1596599425-5534-4-git-send-email-zhangchangzhong@huawei.com
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 net/can/j1939/transport.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 2f3c3afd5071..047118d5270b 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c

@@ -1074,9 +1074,9 @@ 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);

-- 
2.28.0

From: Zhang Changzhong <redacted>

Currently j1939_tp_im_involved_anydir() in j1939_tp_recv() check the previously
set flags J1939_ECU_LOCAL_DST and J1939_ECU_LOCAL_SRC of incoming skb, thus
multipacket broadcast message was aborted by receive side because it may come
from remote ECUs and have no exact dst address. Similarly, j1939_tp_cmd_recv()
and j1939_xtp_rx_dat() didn't process broadcast message.

So fix it by checking and process broadcast message in j1939_tp_recv(),
j1939_tp_cmd_recv() and j1939_xtp_rx_dat().

Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Signed-off-by: Zhang Changzhong <redacted>
Link: https://lore.kernel.org/r/1596599425-5534-2-git-send-email-zhangchangzhong@huawei.com
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 net/can/j1939/transport.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 5cf107cb447c..868ecb2bfa45 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c

@@ -1673,8 +1673,12 @@ 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);

@@ -1865,6 +1869,13 @@ 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 +1967,7 @@ 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 +2031,7 @@ 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) {

-- 
2.28.0

From: Zhang Changzhong <redacted>

If j1939_xtp_rx_dat_one() receive last frame of multipacket broadcast message,
j1939_session_timers_cancel() should be called to cancel rxtimer.

Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Signed-off-by: Zhang Changzhong <redacted>
Link: https://lore.kernel.org/r/1596599425-5534-3-git-send-email-zhangchangzhong@huawei.com
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 net/can/j1939/transport.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 868ecb2bfa45..2f3c3afd5071 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c

@@ -1824,6 +1824,7 @@ static void j1939_xtp_rx_dat_one(struct j1939_session *session,
 	}
 
 	if (final) {
+		j1939_session_timers_cancel(session);
 		j1939_session_completed(session);
 	} else if (do_cts_eoma) {
 		j1939_tp_set_rxtimeout(session, 1250);

-- 
2.28.0

From: Zhang Changzhong <redacted>

According to SAE J1939/21 (Chapter 5.12.3 and APPENDIX C), for transmit side
the required time interval between packets of a multipacket broadcast message
is 50 to 200 ms, the responder shall use a timeout of 250ms (provides margin
allowing for the maximumm spacing of 200ms). For receive side a timeout will
occur when a time of greater than 750 ms elapsed between two message packets
when more packets were expected.

So this patch fix and add rxtimer for multipacket broadcast session.

Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Signed-off-by: Zhang Changzhong <redacted>
Link: https://lore.kernel.org/r/1596599425-5534-5-git-send-email-zhangchangzhong@huawei.com
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 net/can/j1939/transport.c | 28 ++++++++++++++++++++--------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 047118d5270b..a8dd956b5e8e 100644
--- a/net/can/j1939/transport.c
+++ b/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);
 

@@ -1687,11 +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);

@@ -1742,6 +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;
 

@@ -1817,6 +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)

@@ -1826,6 +1835,9 @@ 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)

-- 
2.28.0

From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: Sat, 15 Aug 2020 11:21:12 +0200

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.

Pulled, thanks Marc.