| Message ID | 20210802064134.1068-1-caihuoqing@baidu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: stkwebcam: Use usb_get_dev() for the reference count of udev | expand |
Hello, Salah I have read your patch https://lore.kernel.org/patchwork/patch/1466782/ so I try to fix the same issue in stkwebcam: may I add "Reported-by: Salah Triki <salah.triki@gmail.com>" ask for your comfirmation if not, I will remove it. > -----Original Message----- > From: Cai,Huoqing <caihuoqing@baidu.com> > Sent: 2021年8月2日 14:42 > To: mchehab@kernel.org; hverkuil-cisco@xs4all.nl; paskripkin@gmail.com > Cc: linux-media@vger.kernel.org; Cai,Huoqing <caihuoqing@baidu.com> > Subject: [PATCH] media: stkwebcam: Use usb_get_dev() for the reference count > of udev > > Use usb_get_dev() to increment the reference count of the usb device structure > in order to avoid releasing the structure while it is still in use. And use > usb_put_dev() to decrement the reference count and thus, when it will be equal > to 0 the structure will be released. > > Reported-by: Salah Triki <salah.triki@gmail.com> > Signed-off-by: Cai Huoqing <caihuoqing@baidu.com> > --- > drivers/media/usb/stkwebcam/stk-webcam.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/media/usb/stkwebcam/stk-webcam.c > b/drivers/media/usb/stkwebcam/stk-webcam.c > index 0e231e576dc3..b54a23c6842e 100644 > --- a/drivers/media/usb/stkwebcam/stk-webcam.c > +++ b/drivers/media/usb/stkwebcam/stk-webcam.c > @@ -1234,6 +1234,7 @@ static void stk_v4l_dev_release(struct video_device > *vd) > if (dev->sio_bufs != NULL || dev->isobufs != NULL) > pr_err("We are leaking memory\n"); > usb_put_intf(dev->interface); > + usb_put_dev(dev->udev); > } > > static const struct video_device stk_v4l_data = { @@ -1309,7 +1310,7 @@ > static int stk_camera_probe(struct usb_interface *interface, > init_waitqueue_head(&dev->wait_frame); > dev->first_init = 1; /* webcam LED management */ > > - dev->udev = udev; > + dev->udev = usb_get_dev(udev); > dev->interface = interface; > usb_get_intf(interface); > > -- > 2.25.1
diff --git a/drivers/media/usb/stkwebcam/stk-webcam.c b/drivers/media/usb/stkwebcam/stk-webcam.c index 0e231e576dc3..b54a23c6842e 100644 --- a/drivers/media/usb/stkwebcam/stk-webcam.c +++ b/drivers/media/usb/stkwebcam/stk-webcam.c @@ -1234,6 +1234,7 @@ static void stk_v4l_dev_release(struct video_device *vd) if (dev->sio_bufs != NULL || dev->isobufs != NULL) pr_err("We are leaking memory\n"); usb_put_intf(dev->interface); + usb_put_dev(dev->udev); } static const struct video_device stk_v4l_data = { @@ -1309,7 +1310,7 @@ static int stk_camera_probe(struct usb_interface *interface, init_waitqueue_head(&dev->wait_frame); dev->first_init = 1; /* webcam LED management */ - dev->udev = udev; + dev->udev = usb_get_dev(udev); dev->interface = interface; usb_get_intf(interface);
Use usb_get_dev() to increment the reference count of the usb device structure in order to avoid releasing the structure while it is still in use. And use usb_put_dev() to decrement the reference count and thus, when it will be equal to 0 the structure will be released. Reported-by: Salah Triki <salah.triki@gmail.com> Signed-off-by: Cai Huoqing <caihuoqing@baidu.com> --- drivers/media/usb/stkwebcam/stk-webcam.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)