netdev - Re: [PATCH 4/5] usb: usbnet: Add validation of dev->maxpacket to usbnet

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 15 Feb 2012 20:34:02 +0100
From:	Oliver Neukum <oliver@...kum.org>
To:	Toby Gray <toby.gray@...lvnc.com>
Cc:	Toby Gray <tg@...lvnc.com>, Oliver Neukum <oliver@...kum.name>,
	"Greg Kroah-Hartman" <gregkh@...uxfoundation.org>,
	linux-usb@...r.kernel.org, netdev@...r.kernel.org,
	alexey.orishko@...il.com
Subject: Re: [PATCH 4/5] usb: usbnet: Add validation of dev->maxpacket to usbnet

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@...lvnc.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@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html