[PATCH v4 2/2] media: uvcvideo: Fix crash during unbind if gpio unit is in use

Ricardo Ribalda posted 2 patches 2 weeks, 4 days ago
[PATCH v4 2/2] media: uvcvideo: Fix crash during unbind if gpio unit is in use
Posted by Ricardo Ribalda 2 weeks, 4 days ago
We used the wrong device for the device managed functions. We used the
usb device, when we should be using the interface device.

If we unbind the driver from the usb interface, the cleanup functions
are never called. In our case, the IRQ is never disabled.

If an IRQ is triggered, it will try to access memory sections that are
already free, causing an OOPS.

Luckily this bug has small impact, as it is only affected by devices
with gpio units and the user has to unbind the device, a disconnect will
not trigger this error.

Cc: stable@vger.kernel.org
Fixes: 2886477ff987 ("media: uvcvideo: Implement UVC_EXT_GPIO_UNIT")
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/media/usb/uvc/uvc_driver.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
index 2735fccdf454..c1b2fb7f1428 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -1295,14 +1295,14 @@ static int uvc_gpio_parse(struct uvc_device *dev)
 	struct gpio_desc *gpio_privacy;
 	int irq;
 
-	gpio_privacy = devm_gpiod_get_optional(&dev->udev->dev, "privacy",
+	gpio_privacy = devm_gpiod_get_optional(&dev->intf->dev, "privacy",
 					       GPIOD_IN);
 	if (IS_ERR_OR_NULL(gpio_privacy))
 		return PTR_ERR_OR_ZERO(gpio_privacy);
 
 	irq = gpiod_to_irq(gpio_privacy);
 	if (irq < 0)
-		return dev_err_probe(&dev->udev->dev, irq,
+		return dev_err_probe(&dev->intf->dev, irq,
 				     "No IRQ for privacy GPIO\n");
 
 	unit = uvc_alloc_new_entity(dev, UVC_EXT_GPIO_UNIT,
@@ -1333,7 +1333,7 @@ static int uvc_gpio_init_irq(struct uvc_device *dev)
 	if (!unit || unit->gpio.irq < 0)
 		return 0;
 
-	return devm_request_threaded_irq(&dev->udev->dev, unit->gpio.irq, NULL,
+	return devm_request_threaded_irq(&dev->intf->dev, unit->gpio.irq, NULL,
 					 uvc_gpio_irq,
 					 IRQF_ONESHOT | IRQF_TRIGGER_FALLING |
 					 IRQF_TRIGGER_RISING,

-- 
2.47.0.199.ga7371fff76-goog