[PATCH 5.4 28/47] media: gp8psk: initialize stats at power control logic

From: Greg Kroah-Hartman
Date: Mon Jan 04 2021 - 11:11:51 EST


From: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>

commit d0ac1a26ed5943127cb0156148735f5f52a07075 upstream.

As reported on:
https://lore.kernel.org/linux-media/20190627222020.45909-1-willemdebruijn.kernel@xxxxxxxxx/

if gp8psk_usb_in_op() returns an error, the status var is not
initialized. Yet, this var is used later on, in order to
identify:
- if the device was already started;
- if firmware has loaded;
- if the LNBf was powered on.

Using status = 0 seems to ensure that everything will be
properly powered up.

So, instead of the proposed solution, let's just set
status = 0.

Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx>
Reported-by: Willem de Bruijn <willemb@xxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/media/usb/dvb-usb/gp8psk.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/media/usb/dvb-usb/gp8psk.c
+++ b/drivers/media/usb/dvb-usb/gp8psk.c
@@ -182,7 +182,7 @@ out_rel_fw:

static int gp8psk_power_ctrl(struct dvb_usb_device *d, int onoff)
{
- u8 status, buf;
+ u8 status = 0, buf;
int gp_product_id = le16_to_cpu(d->udev->descriptor.idProduct);

if (onoff) {