| Message ID | 1329317261-3406-5-git-send-email-toby.gray@realvnc.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
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@realvnc.com> > --- > 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. Regards Oliver -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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@realvnc.com> >> --- >> 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 netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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; + } if ((dev->driver_info->flags & FLAG_WLAN) != 0) SET_NETDEV_DEVTYPE(net, &wlan_type);
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@realvnc.com> --- drivers/net/usb/usbnet.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)