Re: [PATCH V4 2/2] wifi: ath6kl: remove ath6kl_usb_submit_ctrl_in

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Aug 26, 2024 at 08:29:57PM +0800, Edward Adam Davis wrote:
> ath6kl_usb_submit_ctrl_in() did not take into account the situation where
> the length of the data read from the device is not equal to the len, and
> such missing judgments will result in subsequent code using incorrect data.
> 
> usb_control_msg_recv() handles the abnormal length of the returned data,
> so using it directly.
> 
> Suggested-by: Greg KH <gregkh@linuxfoundation.org>
> Signed-off-by: Edward Adam Davis <eadavis@qq.com>
> ---
>  drivers/net/wireless/ath/ath6kl/usb.c | 39 +++------------------------
>  1 file changed, 3 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath6kl/usb.c b/drivers/net/wireless/ath/ath6kl/usb.c
> index 0458b5a078e1..b1fc66d823b8 100644
> --- a/drivers/net/wireless/ath/ath6kl/usb.c
> +++ b/drivers/net/wireless/ath/ath6kl/usb.c
> @@ -901,40 +901,6 @@ static int ath6kl_usb_submit_ctrl_out(struct ath6kl_usb *ar_usb,
>  	return 0;
>  }
>  
> -static int ath6kl_usb_submit_ctrl_in(struct ath6kl_usb *ar_usb,
> -				  u8 req, u16 value, u16 index, void *data,
> -				  u32 size)
> -{
> -	u8 *buf = NULL;
> -	int ret;
> -
> -	if (size > 0) {
> -		buf = kmalloc(size, GFP_KERNEL);
> -		if (buf == NULL)
> -			return -ENOMEM;
> -	}
> -
> -	/* note: if successful returns number of bytes transfered */
> -	ret = usb_control_msg(ar_usb->udev,
> -				 usb_rcvctrlpipe(ar_usb->udev, 0),
> -				 req,
> -				 USB_DIR_IN | USB_TYPE_VENDOR |
> -				 USB_RECIP_DEVICE, value, index, buf,
> -				 size, 2000);
> -
> -	if (ret < 0) {
> -		ath6kl_warn("Failed to read usb control message: %d\n", ret);
> -		kfree(buf);
> -		return ret;
> -	}
> -
> -	memcpy((u8 *) data, buf, size);
> -
> -	kfree(buf);
> -
> -	return 0;
> -}
> -
>  static int ath6kl_usb_ctrl_msg_exchange(struct ath6kl_usb *ar_usb,
>  				     u8 req_val, u8 *req_buf, u32 req_len,
>  				     u8 resp_val, u8 *resp_buf, u32 *resp_len)
> @@ -954,8 +920,9 @@ static int ath6kl_usb_ctrl_msg_exchange(struct ath6kl_usb *ar_usb,
>  	}
>  
>  	/* get response */
> -	ret = ath6kl_usb_submit_ctrl_in(ar_usb, resp_val, 0, 0,
> -					resp_buf, *resp_len);
> +	ret = usb_control_msg_recv(ar_usb->udev, 0, resp_val,
> +				USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
> +				0, 0, resp_buf, *resp_len, 2000, GFP_KERNEL);

You didn't run checkpatch on this :(