| Message ID | 20190729101444.2191-1-baijiaju1990@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: usb: msi2500: Fix a possible null-pointer dereference in msi2500_stop_streaming() | expand |
diff --git a/drivers/media/usb/msi2500/msi2500.c b/drivers/media/usb/msi2500/msi2500.c index 4c9b2a12acfb..a6ecd9bd35f9 100644 --- a/drivers/media/usb/msi2500/msi2500.c +++ b/drivers/media/usb/msi2500/msi2500.c @@ -874,7 +874,7 @@ static void msi2500_stop_streaming(struct vb2_queue *vq) /* according to tests, at least 700us delay is required */ msleep(20); - if (!msi2500_ctrl_msg(dev, CMD_STOP_STREAMING, 0)) { + if (dev->udev && !msi2500_ctrl_msg(dev, CMD_STOP_STREAMING, 0)) { /* sleep USB IF / ADC */ msi2500_ctrl_msg(dev, CMD_WREG, 0x01000003); }
In msi2500_stop_streaming(), there is an if statement on line 870 to check whether dev->udev is NULL: if (dev->udev) When dev->udev is NULL, it is used on line 877: msi2500_ctrl_msg(dev, CMD_STOP_STREAMING, 0) usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), ...) Thus, a possible null-pointer dereference may occur. To fix this bug, dev->udev is checked before calling msi2500_ctrl_msg(). This bug is found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> --- drivers/media/usb/msi2500/msi2500.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)