[media] gspca_main: Locking fixes 1
The gspca_dev->streaming boolean is protected against multiple access
through gspca_dev->queue_lock everywhere except for 2 places. This patch
fixes this by bringing it under the lock in vidioc_streamoff. And by
removing the check for gspca_dev->streaming in gspca_disconnect,
the destroy_urbs call may be called multiple times (and is protected
by the usb_lock) and calling wake_up_interruptible can also always be done
safely.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c
index 4429700..74626b6 100644
--- a/drivers/media/video/gspca/gspca.c
+++ b/drivers/media/video/gspca/gspca.c
@@ -1630,11 +1630,15 @@
if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
return -EINVAL;
- if (!gspca_dev->streaming)
- return 0;
+
if (mutex_lock_interruptible(&gspca_dev->queue_lock))
return -ERESTARTSYS;
+ if (!gspca_dev->streaming) {
+ ret = 0;
+ goto out;
+ }
+
/* check the capture file */
if (gspca_dev->capt_file != file) {
ret = -EBUSY;
@@ -2341,12 +2345,11 @@
PDEBUG(D_PROBE, "%s disconnect",
video_device_node_name(&gspca_dev->vdev));
mutex_lock(&gspca_dev->usb_lock);
- gspca_dev->present = 0;
- if (gspca_dev->streaming) {
- destroy_urbs(gspca_dev);
- wake_up_interruptible(&gspca_dev->wq);
- }
+ gspca_dev->present = 0;
+ wake_up_interruptible(&gspca_dev->wq);
+
+ destroy_urbs(gspca_dev);
#if defined(CONFIG_INPUT) || defined(CONFIG_INPUT_MODULE)
gspca_input_destroy_urb(gspca_dev);