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@xxxxxxxxx>
---
drivers/media/usb/msi2500/msi2500.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
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);
}
--
2.17.0
