After a reset packet sizes and device mtu can change and need
to be reevaluated to calculate queue sizes.
Malicious devices can set this to zero and we divide by it.
Introduce sanity checking.
Reported-and-tested-by: syzbot+6102c120be558c885f04@syzkaller.appspotmail.com
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
{
enum usb_device_speed speed = dev->udev->speed;
+ if (!dev->rx_urb_size || !dev->hard_mtu)
+ goto insanity;
switch (speed) {
case USB_SPEED_HIGH:
dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
break;
default:
+insanity:
dev->rx_qlen = dev->tx_qlen = 4;
}
}