On 15/02/12 19:34, Oliver Neukum wrote:
Am Mittwoch, 15. Februar 2012, 15:47:40 schrieb Toby Gray:Several parts of usbnet rely on dev->maxpacket not being set to 0 to prevent division by zero errors. This adds validation of the dev->maxpacket value being non-zero before treating the device probe as successful. Signed-off-by: Toby Gray<toby.gray@xxxxxxxxxxx> --- drivers/net/usb/usbnet.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 4ccd316..1491c90 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1427,6 +1427,10 @@ usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod) dev->rx_urb_size = dev->hard_mtu; if (!dev->maxpacket) dev->maxpacket = usb_maxpacket(dev->udev, dev->out, 1); + if (!dev->maxpacket) { + status = -ENODEV; + goto out3;Hm. I am sceptical. If this happens a subdriver is buggy. We should not hide that. I am afraid I have to reject this patch.
That's understandable, I almost didn't include it in the series. The only reason I added this to the patch series was because I spent a while trying to track down a division by zero, when it turns out it was actually due to dev->maxpacket being zero when usbnet_start_xmit tried to calculate length % dev->maxpacket.
Would you prefer that I drop this patch entirely or just change it to something like a BUG_ON?
Regards, Toby -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
