From: Laurent Pinchart laurent.pinchart@ideasonboard.com
commit 8c279e9394cade640ed86ec6c6645a0e7df5e0b6 upstream.
When parsing the UVC control descriptors fails, the error path tries to cleanup a media device that hasn't been initialised, potentially resulting in a crash. Fix this by initialising the media device before the error handling path can be reached.
Fixes: 5a254d751e52 ("[media] uvcvideo: Register a v4l2_device") Reported-by: syzbot+c86454eb3af9e8a4da20@syzkaller.appspotmail.com Signed-off-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/media/usb/uvc/uvc_driver.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-)
--- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -2124,6 +2124,20 @@ static int uvc_probe(struct usb_interfac sizeof(dev->name) - len); }
+ /* Initialize the media device. */ +#ifdef CONFIG_MEDIA_CONTROLLER + dev->mdev.dev = &intf->dev; + strscpy(dev->mdev.model, dev->name, sizeof(dev->mdev.model)); + if (udev->serial) + strscpy(dev->mdev.serial, udev->serial, + sizeof(dev->mdev.serial)); + usb_make_path(udev, dev->mdev.bus_info, sizeof(dev->mdev.bus_info)); + dev->mdev.hw_revision = le16_to_cpu(udev->descriptor.bcdDevice); + media_device_init(&dev->mdev); + + dev->vdev.mdev = &dev->mdev; +#endif + /* Parse the Video Class control descriptor. */ if (uvc_parse_control(dev) < 0) { uvc_trace(UVC_TRACE_PROBE, "Unable to parse UVC " @@ -2144,19 +2158,7 @@ static int uvc_probe(struct usb_interfac "linux-uvc-devel mailing list.\n"); }
- /* Initialize the media device and register the V4L2 device. */ -#ifdef CONFIG_MEDIA_CONTROLLER - dev->mdev.dev = &intf->dev; - strlcpy(dev->mdev.model, dev->name, sizeof(dev->mdev.model)); - if (udev->serial) - strlcpy(dev->mdev.serial, udev->serial, - sizeof(dev->mdev.serial)); - strcpy(dev->mdev.bus_info, udev->devpath); - dev->mdev.hw_revision = le16_to_cpu(udev->descriptor.bcdDevice); - media_device_init(&dev->mdev); - - dev->vdev.mdev = &dev->mdev; -#endif + /* Register the V4L2 device. */ if (v4l2_device_register(&intf->dev, &dev->vdev) < 0) goto error;