media: uvcvideo: Fix crash during unbind if gpio unit is in use

[ Upstream commit a9ea1a3d88b7947ce8cadb2afceee7a54872bbc5 ]

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.

We cannot use the function devm_request_threaded_irq here. The devm_*
clean functions may be called after the main structure is released by
uvc_delete.

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>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://lore.kernel.org/r/20241106-uvc-crashrmmod-v6-1-fbf9781c6e83@chromium.org
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
index 92af9caf6b5dbed7e442583d0b77b3777f339a29..47a6cedd5578c9025f871b7ceddd82a5e22fe5e1 100644 (file)
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -1247,14 +1247,14 @@ 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_entity(UVC_EXT_GPIO_UNIT, UVC_EXT_GPIO_UNIT_ID, 0, 1);
@@ -1280,15 +1280,27 @@ static int uvc_gpio_parse(struct uvc_device *dev)
 static int uvc_gpio_init_irq(struct uvc_device *dev)
 {
        struct uvc_entity *unit = dev->gpio_unit;
+       int ret;
 
        if (!unit || unit->gpio.irq < 0)
                return 0;
 
-       return devm_request_threaded_irq(&dev->udev->dev, unit->gpio.irq, NULL,
-                                        uvc_gpio_irq,
-                                        IRQF_ONESHOT | IRQF_TRIGGER_FALLING |
-                                        IRQF_TRIGGER_RISING,
-                                        "uvc_privacy_gpio", dev);
+       ret = request_threaded_irq(unit->gpio.irq, NULL, uvc_gpio_irq,
+                                  IRQF_ONESHOT | IRQF_TRIGGER_FALLING |
+                                  IRQF_TRIGGER_RISING,
+                                  "uvc_privacy_gpio", dev);
+
+       unit->gpio.initialized = !ret;
+
+       return ret;
+}
+
+static void uvc_gpio_deinit(struct uvc_device *dev)
+{
+       if (!dev->gpio_unit || !dev->gpio_unit->gpio.initialized)
+               return;
+
+       free_irq(dev->gpio_unit->gpio.irq, dev);
 }
 
 /* ------------------------------------------------------------------------
@@ -1882,6 +1894,8 @@ static void uvc_unregister_video(struct uvc_device *dev)
 {
        struct uvc_streaming *stream;
 
+       uvc_gpio_deinit(dev);
+
        list_for_each_entry(stream, &dev->streams, list) {
                /* Nothing to do here, continue. */
                if (!video_is_registered(&stream->vdev))

diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 33e7475d4e64ac79e26c1af3d479d2043690fb8b..475bf185be8a8d75be772a3dfa0a3709e576ff6b 100644 (file)
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -227,6 +227,7 @@ struct uvc_entity {
                        u8  *bmControls;
                        struct gpio_desc *gpio_privacy;
                        int irq;
+                       bool initialized;
                } gpio;
        };