Re: [PATCH] usb: max-3421: fix potential shift out-of-bounds in max3421_hub_control()

[Krzysztof Kozlowski]

On 25/06/2023 19:12, Zhang Shurong wrote:
> Fix potential shift out-of-bounds in max3421_hub_control()
> ClearPortFeature handling and SetPortFeature handling.
> 
> wValue may be greater than 32 which can not be used for shifting.

You need to use proper name after copying the commit msg...

> 
> similar patch:
> https://patchwork.kernel.org/patch/12162547

This does not belong to commit msg, but rather --- .

> 
> Signed-off-by: Zhang Shurong <zhang_shurong@xxxxxxxxxxx>
> ---
>  drivers/usb/host/max3421-hcd.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/host/max3421-hcd.c b/drivers/usb/host/max3421-hcd.c
> index d152d72de126..035cd6abc2f6 100644
> --- a/drivers/usb/host/max3421-hcd.c
> +++ b/drivers/usb/host/max3421-hcd.c
> @@ -1688,6 +1688,8 @@ max3421_hub_control(struct usb_hcd *hcd, u16 type_req, u16 value, u16 index,
>  						!pdata->vbus_active_level);
>  			fallthrough;
>  		default:
> +			if (value >= 32)
> +				goto error;
>  			max3421_hcd->port_status &= ~(1 << value);
>  		}
>  		break;
> @@ -1741,6 +1743,8 @@ max3421_hub_control(struct usb_hcd *hcd, u16 type_req, u16 value, u16 index,
>  			max3421_reset_port(hcd);
>  			fallthrough;
>  		default:
> +			if (value >= 32)
> +				goto error;

I am not sure if performing first port reset and then validating the
arguments is the correct way.

>  			if ((max3421_hcd->port_status & USB_PORT_STAT_POWER)
>  			    != 0)
>  				max3421_hcd->port_status |= (1 << value);

Best regards,
Krzysztof