Merge tag 'linux-can-fixes-for-6.14-20250208' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2025-02-08

The first patch is by Reyders Morales and fixes a code example in the
CAN ISO15765-2 documentation.

The next patch is contributed by Alexander Hölzl and fixes sending of
J1939 messages with zero data length.

Fedor Pchelkin's patch for the ctucanfd driver adds a missing handling
for an skb allocation error.

Krzysztof Kozlowski contributes a patch for the c_can driver to fix
unbalanced runtime PM disable in error path.

The next patch is by Vincent Mailhol and fixes a NULL pointer
dereference on udev->serial in the etas_es58x driver.

The patch is by Robin van der Gracht and fixes the handling for an skb
allocation error.

* tag 'linux-can-fixes-for-6.14-20250208' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
  can: rockchip: rkcanfd_handle_rx_fifo_overflow_int(): bail out if skb cannot be allocated
  can: etas_es58x: fix potential NULL pointer dereference on udev->serial
  can: c_can: fix unbalanced runtime PM disable in error path
  can: ctucanfd: handle skb allocation failure
  can: j1939: j1939_sk_send_loop(): fix unable to send messages with data length zero
  Documentation/networking: fix basic node example document ISO 15765-2
====================

Link: https://patch.msgid.link/20250208115120.237274-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

4 files changed, 15 insertions, 8 deletions

diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
index 6cba9717a6d8..399844809bbe 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -385,15 +385,16 @@ static int c_can_plat_probe(struct platform_device *pdev)
 	if (ret) {
 		dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
 			KBUILD_MODNAME, ret);
-		goto exit_free_device;
+		goto exit_pm_runtime;
 	}
 
 	dev_info(&pdev->dev, "%s device registered (regs=%p, irq=%d)\n",
 		 KBUILD_MODNAME, priv->base, dev->irq);
 	return 0;
 
-exit_free_device:
+exit_pm_runtime:
 	pm_runtime_disable(priv->device);
+exit_free_device:
 	free_c_can_dev(dev);
 exit:
 	dev_err(&pdev->dev, "probe failed\n");
diff --git a/drivers/net/can/ctucanfd/ctucanfd_base.c b/drivers/net/can/ctucanfd/ctucanfd_base.c
index 64c349fd4600..f65c1a1e05cc 100644
--- a/drivers/net/can/ctucanfd/ctucanfd_base.c
+++ b/drivers/net/can/ctucanfd/ctucanfd_base.c
@@ -867,10 +867,12 @@ static void ctucan_err_interrupt(struct net_device *ndev, u32 isr)
 			}
 			break;
 		case CAN_STATE_ERROR_ACTIVE:
-			cf->can_id |= CAN_ERR_CNT;
-			cf->data[1] = CAN_ERR_CRTL_ACTIVE;
-			cf->data[6] = bec.txerr;
-			cf->data[7] = bec.rxerr;
+			if (skb) {
+				cf->can_id |= CAN_ERR_CNT;
+				cf->data[1] = CAN_ERR_CRTL_ACTIVE;
+				cf->data[6] = bec.txerr;
+				cf->data[7] = bec.rxerr;
+			}
 			break;
 		default:
 			netdev_warn(ndev, "unhandled error state (%d:%s)!\n",
diff --git a/drivers/net/can/rockchip/rockchip_canfd-core.c b/drivers/net/can/rockchip/rockchip_canfd-core.c
index df18c85fc078..d9a937ba126c 100644
--- a/drivers/net/can/rockchip/rockchip_canfd-core.c
+++ b/drivers/net/can/rockchip/rockchip_canfd-core.c
@@ -622,7 +622,7 @@ rkcanfd_handle_rx_fifo_overflow_int(struct rkcanfd_priv *priv)
 	netdev_dbg(priv->ndev, "RX-FIFO overflow\n");
 
 	skb = rkcanfd_alloc_can_err_skb(priv, &cf, &timestamp);
-	if (skb)
+	if (!skb)
 		return 0;
 
 	rkcanfd_get_berr_counter_corrected(priv, &bec);
diff --git a/drivers/net/can/usb/etas_es58x/es58x_devlink.c b/drivers/net/can/usb/etas_es58x/es58x_devlink.c
index eee20839d96f..0d155eb1b9e9 100644
--- a/drivers/net/can/usb/etas_es58x/es58x_devlink.c
+++ b/drivers/net/can/usb/etas_es58x/es58x_devlink.c
@@ -248,7 +248,11 @@ static int es58x_devlink_info_get(struct devlink *devlink,
 			return ret;
 	}
 
-	return devlink_info_serial_number_put(req, es58x_dev->udev->serial);
+	if (es58x_dev->udev->serial)
+		ret = devlink_info_serial_number_put(req,
+						     es58x_dev->udev->serial);
+
+	return ret;
 }
 
 const struct devlink_ops es58x_dl_ops = {