Merging upstream version 6.9.8.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 20 insertions, 7 deletions

diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c
index a6fb89fa62..7e8a20f2fc 100644
--- a/net/can/j1939/main.c
+++ b/net/can/j1939/main.c
@@ -30,10 +30,6 @@ MODULE_ALIAS("can-proto-" __stringify(CAN_J1939));
 /* CAN_HDR: #bytes before can_frame data part */
 #define J1939_CAN_HDR (offsetof(struct can_frame, data))
 
-/* CAN_FTR: #bytes beyond data part */
-#define J1939_CAN_FTR (sizeof(struct can_frame) - J1939_CAN_HDR - \
-		 sizeof(((struct can_frame *)0)->data))
-
 /* lowest layer */
 static void j1939_can_recv(struct sk_buff *iskb, void *data)
 {
@@ -342,7 +338,7 @@ int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb)
 	memset(cf, 0, J1939_CAN_HDR);
 
 	/* make it a full can frame again */
-	skb_put(skb, J1939_CAN_FTR + (8 - dlc));
+	skb_put_zero(skb, 8 - dlc);
 
 	canid = CAN_EFF_FLAG |
 		(skcb->priority << 26) |
diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index fe3df23a25..4be73de503 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -1593,8 +1593,8 @@ j1939_session *j1939_xtp_rx_rts_session_new(struct j1939_priv *priv,
 	struct j1939_sk_buff_cb skcb = *j1939_skb_to_cb(skb);
 	struct j1939_session *session;
 	const u8 *dat;
+	int len, ret;
 	pgn_t pgn;
-	int len;
 
 	netdev_dbg(priv->ndev, "%s\n", __func__);
 
@@ -1653,7 +1653,22 @@ j1939_session *j1939_xtp_rx_rts_session_new(struct j1939_priv *priv,
 	session->tskey = priv->rx_tskey++;
 	j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_RTS);
 
-	WARN_ON_ONCE(j1939_session_activate(session));
+	ret = j1939_session_activate(session);
+	if (ret) {
+		/* Entering this scope indicates an issue with the J1939 bus.
+		 * Possible scenarios include:
+		 * - A time lapse occurred, and a new session was initiated
+		 *   due to another packet being sent correctly. This could
+		 *   have been caused by too long interrupt, debugger, or being
+		 *   out-scheduled by another task.
+		 * - The bus is receiving numerous erroneous packets, either
+		 *   from a malfunctioning device or during a test scenario.
+		 */
+		netdev_alert(priv->ndev, "%s: 0x%p: concurrent session with same addr (%02x %02x) is already active.\n",
+			     __func__, session, skcb.addr.sa, skcb.addr.da);
+		j1939_session_put(session);
+		return NULL;
+	}
 
 	return session;
 }
@@ -1681,6 +1696,8 @@ static int j1939_xtp_rx_rts_session_active(struct j1939_session *session,
 
 		j1939_session_timers_cancel(session);
 		j1939_session_cancel(session, J1939_XTP_ABORT_BUSY);
+		if (session->transmission)
+			j1939_session_deactivate_activate_next(session);
 
 		return -EBUSY;
 	}