4.14-stable review patch. If anyone has any objections, please let me know.
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commit f9ffcb0a21e1fa8e64d09ed613d884e054ae8191 upstream
kref_init initializes the reference count to 1, not 0. This additional reference is never released since the conversion to reference counters. As a result, uvc_delete is not called anymore when UVC cameras are disconnected. Fix this by adding an additional kref_put in uvc_disconnect and in the probe error path. This also allows to remove the temporary additional reference in uvc_unregister_video.
Fixes: 9d15cd958c17 ("media: uvcvideo: Convert from using an atomic variable to a reference count")
Signed-off-by: Philipp Zabel philipp.zabel@gmail.com Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Signed-off-by: Sudip Mukherjee sudipm.mukherjee@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/usb/uvc/uvc_driver.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-)
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c index 6d22b22cb35b..064d88299adc 100644 --- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -1865,13 +1865,6 @@ static void uvc_unregister_video(struct uvc_device *dev) { struct uvc_streaming *stream;
- /* Unregistering all video devices might result in uvc_delete() being - * called from inside the loop if there's no open file handle. To avoid - * that, increment the refcount before iterating over the streams and - * decrement it when done. - */ - kref_get(&dev->ref); - list_for_each_entry(stream, &dev->streams, list) { if (!video_is_registered(&stream->vdev)) continue; @@ -1880,8 +1873,6 @@ static void uvc_unregister_video(struct uvc_device *dev)
uvc_debugfs_cleanup_stream(stream); } - - kref_put(&dev->ref, uvc_delete); }
static int uvc_register_video(struct uvc_device *dev, @@ -2129,6 +2120,7 @@ static int uvc_probe(struct usb_interface *intf,
error: uvc_unregister_video(dev); + kref_put(&dev->ref, uvc_delete); return -ENODEV; }
@@ -2146,6 +2138,7 @@ static void uvc_disconnect(struct usb_interface *intf) return;
uvc_unregister_video(dev); + kref_put(&dev->ref, uvc_delete); }
static int uvc_suspend(struct usb_interface *intf, pm_message_t message)