Re: [PATCH 01/10] USB: usb_driver_claim_interface: add sanity checking

[Lu Baolu <baolu.lu@linux.intel.com>]

I am sorry. This email was sent out due to an incorrect operation.
Please ignore it. I am sorry for disturbing you.

Best regards,
Baolu

On 03/25/2016 10:58 AM, Lu Baolu wrote:
> From: Oliver Neukum <oneukum@suse.com>
>
> Attacks that trick drivers into passing a NULL pointer
> to usb_driver_claim_interface() using forged descriptors are
> known. This thwarts them by sanity checking.
>
> Signed-off-by: Oliver Neukum <ONeukum@suse.com>
> CC: stable@vger.kernel.org
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  drivers/usb/core/driver.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
> index 56593a9..2057d91 100644
> --- a/drivers/usb/core/driver.c
> +++ b/drivers/usb/core/driver.c
> @@ -502,11 +502,15 @@ static int usb_unbind_interface(struct device *dev)
>  int usb_driver_claim_interface(struct usb_driver *driver,
>  				struct usb_interface *iface, void *priv)
>  {
> -	struct device *dev = &iface->dev;
> +	struct device *dev;
>  	struct usb_device *udev;
>  	int retval = 0;
>  	int lpm_disable_error;
>  
> +	if (!iface)
> +		return -ENODEV;
> +
> +	dev = &iface->dev;
>  	if (dev->driver)
>  		return -EBUSY;
>