[PATCH 1/2] spi: ch341: fix memory leaks on probe failures

[Johan Hovold <johan@kernel.org>]

Make sure to deregister the controller, disable pins, and kill and free
the RX URB on probe failures to mirror disconnect and avoid memory
leaks and use-after-free.

Also add an explicit URB kill on disconnect for symmetry (even if that
is not strictly required as USB core would have stopped it in the
current setup).

Fixes: 8846739f52af ("spi: add ch341a usb2spi driver")
Cc: stable@vger.kernel.org	# 6.11
Cc: Johannes Thumshirn <jth@kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/spi/spi-ch341.c | 36 +++++++++++++++++++++++++-----------
 1 file changed, 25 insertions(+), 11 deletions(-)

diff --git a/drivers/spi/spi-ch341.c b/drivers/spi/spi-ch341.c
index 2fdb1c020339..ea92ba986201 100644
--- a/drivers/spi/spi-ch341.c
+++ b/drivers/spi/spi-ch341.c
@@ -173,17 +173,17 @@ static int ch341_probe(struct usb_interface *intf,
 
 	ch341->tx_buf =
 		devm_kzalloc(&udev->dev, CH341_PACKET_LENGTH, GFP_KERNEL);
-	if (!ch341->tx_buf)
-		return -ENOMEM;
+	if (!ch341->tx_buf) {
+		ret = -ENOMEM;
+		goto err_free_urb;
+	}
 
 	usb_fill_bulk_urb(ch341->rx_urb, udev, ch341->read_pipe, ch341->rx_buf,
 			  ch341->rx_len, ch341_recv, ch341);
 
 	ret = usb_submit_urb(ch341->rx_urb, GFP_KERNEL);
-	if (ret) {
-		usb_free_urb(ch341->rx_urb);
-		return -ENOMEM;
-	}
+	if (ret)
+		goto err_free_urb;
 
 	ctrl->bus_num = -1;
 	ctrl->mode_bits = SPI_CPHA;
@@ -195,21 +195,34 @@ static int ch341_probe(struct usb_interface *intf,
 
 	ret = ch341_config_stream(ch341);
 	if (ret)
-		return ret;
+		goto err_kill_urb;
 
 	ret = ch341_enable_pins(ch341, true);
 	if (ret)
-		return ret;
+		goto err_kill_urb;
 
 	ret = spi_register_controller(ctrl);
 	if (ret)
-		return ret;
+		goto err_disable_pins;
 
 	ch341->spidev = spi_new_device(ctrl, &chip);
-	if (!ch341->spidev)
-		return -ENOMEM;
+	if (!ch341->spidev) {
+		ret = -ENOMEM;
+		goto err_unregister;
+	}
 
 	return 0;
+
+err_unregister:
+	spi_unregister_controller(ctrl);
+err_disable_pins:
+	ch341_enable_pins(ch341, false);
+err_kill_urb:
+	usb_kill_urb(ch341->rx_urb);
+err_free_urb:
+	usb_free_urb(ch341->rx_urb);
+
+	return ret;
 }
 
 static void ch341_disconnect(struct usb_interface *intf)
@@ -219,6 +232,7 @@ static void ch341_disconnect(struct usb_interface *intf)
 	spi_unregister_device(ch341->spidev);
 	spi_unregister_controller(ch341->ctrl);
 	ch341_enable_pins(ch341, false);
+	usb_kill_urb(ch341->rx_urb);
 	usb_free_urb(ch341->rx_urb);
 }
 
-- 
2.52.0