[PATCH v6 1/3] can: at91_can: release the rx-offload on teardown

[Ciprian Costea <ciprianmarian.costea@oss.nxp.com>]

From: Ciprian Marian Costea <ciprianmarian.costea@oss.nxp.com>

at91_can_probe() ignores the return value of can_rx_offload_add_timestamp()
and can_rx_offload_del() is never called, neither on the register_candev()
error path nor in at91_can_remove(). Any skbs left in the offload queues
are leaked.

Check the return value and call can_rx_offload_del() on both paths.

Fixes: 137f59d5dab4 ("can: at91_can: switch to rx-offload implementation")
Signed-off-by: Ciprian Marian Costea <ciprianmarian.costea@oss.nxp.com>
---
 drivers/net/can/at91_can.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
index 58da323f14d7..09aa676a03fb 100644
--- a/drivers/net/can/at91_can.c
+++ b/drivers/net/can/at91_can.c
@@ -1123,7 +1123,11 @@ static int at91_can_probe(struct platform_device *pdev)
 	priv->offload.mb_first = devtype_data->rx_first;
 	priv->offload.mb_last = devtype_data->rx_last;
 
-	can_rx_offload_add_timestamp(dev, &priv->offload);
+	err = can_rx_offload_add_timestamp(dev, &priv->offload);
+	if (err) {
+		dev_err(&pdev->dev, "can_rx_offload_add_timestamp() failed\n");
+		goto exit_free;
+	}
 
 	if (transceiver)
 		priv->can.bitrate_max = transceiver->attrs.max_link_rate;
@@ -1137,7 +1141,7 @@ static int at91_can_probe(struct platform_device *pdev)
 	err = register_candev(dev);
 	if (err) {
 		dev_err(&pdev->dev, "registering netdev failed\n");
-		goto exit_free;
+		goto exit_offload;
 	}
 
 	dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
@@ -1145,6 +1149,8 @@ static int at91_can_probe(struct platform_device *pdev)
 
 	return 0;
 
+ exit_offload:
+	can_rx_offload_del(&priv->offload);
  exit_free:
 	free_candev(dev);
  exit_iounmap:
@@ -1165,6 +1171,8 @@ static void at91_can_remove(struct platform_device *pdev)
 
 	unregister_netdev(dev);
 
+	can_rx_offload_del(&priv->offload);
+
 	iounmap(priv->reg_base);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-- 
2.43.0