Re: [PATCHv2] usbnet: sanity check for maxpacket
From: Johan Hovold <johan@kernel.org>
Date: 2021-10-21 12:38:32
Also in:
linux-usb
On Thu, Oct 21, 2021 at 02:29:44PM +0200, Oliver Neukum wrote:
maxpacket of 0 makes no sense and oopses as we need to divide by it. Give up. V2: fixed typo in log and stylistic issues
Changelog goes below the ---
Signed-off-by: Oliver Neukum <oneukum@suse.com> Reported-by: syzbot+76bb1d34ffa0adc03baa@syzkaller.appspotmail.com
Again, Reviewed-by: Johan Hovold <johan@kernel.org>
quoted hunk ↗ jump to hunk
--- drivers/net/usb/usbnet.c | 4 ++++ 1 file changed, 4 insertions(+)diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 840c1c2ab16a..80432ee0ce69 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c@@ -1788,6 +1788,10 @@ usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod) if (!dev->rx_urb_size) dev->rx_urb_size = dev->hard_mtu; dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1); + if (dev->maxpacket == 0) { + /* that is a broken device */ + goto out4; + } /* let userspace know we have a random address */ if (ether_addr_equal(net->dev_addr, node_id))