Re: [PATCH 1/5] staging: vt6656: Fix non zero logical return of, usb_control_msg

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 06/01/2020 21:45, Quentin Deslandes wrote:
> On 01/03/20 13:58:08, Dan Carpenter wrote:
>> On Fri, Dec 20, 2019 at 09:14:59PM +0000, Malcolm Priestley wrote:
>>> Starting with commit 59608cb1de1856
>>> ("staging: vt6656: clean function's error path in usbpipe.c")
>>> the usb control functions have returned errors throughout driver
>>> with only logical variable checking.
>>
>> Use the Fixes tag for this.
>>
>> Fixes: 59608cb1de18 ("staging: vt6656: clean function's error path in usbpipe.c")
>>
>> 12 digits to the hash.  Add Quentin to the CC list.
>>
>>>
>>> However, usb_control_msg return the amount of bytes transferred
>>> this means that normal operation causes errors.
>>>
>>> Correct the return function so only return zero when transfer
>>> is successful.
>>>
>>> Cc: stable <stable@xxxxxxxxxxxxxxx> # v5.3+
>>> Signed-off-by: Malcolm Priestley <tvboxspy@xxxxxxxxx>
>>> ---
>>>  drivers/staging/vt6656/usbpipe.c | 8 ++++++--
>>>  1 file changed, 6 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/staging/vt6656/usbpipe.c b/drivers/staging/vt6656/usbpipe.c
>>> index d3304df6bd53..488ebd98773d 100644
>>> --- a/drivers/staging/vt6656/usbpipe.c
>>> +++ b/drivers/staging/vt6656/usbpipe.c
>>> @@ -59,7 +59,9 @@ int vnt_control_out(struct vnt_private *priv, u8 request, u16 value,
>>>  
>>>  	kfree(usb_buffer);
>>>  
>>> -	if (ret >= 0 && ret < (int)length)
>>> +	if (ret == (int)length)
>>
>> No need for this cast (no need in the original either).
>>
>>> +		ret = 0;
>>> +	else
>>>  		ret = -EIO;
>>
>> It would be better to preserve the error codes from usb_control_msg().
>>
>> 	if (ret == length)
>> 		ret = 0;
>> 	else if (ret >= 0)
>> 		ret = -EIO;
>>
>> regards,
>> dan carpenter
>>
> 
> Thanks for CC.
> 
> Nice catch. Dan is right, we should forward any error code from
> usb_control_msg().

This is already in linux-next.

So I will do a fix up patch by the end of this cycle.

Regards


Malcolm
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel



[Index of Archives]     [Linux Driver Backports]     [DMA Engine]     [Linux GPIO]     [Linux SPI]     [Video for Linux]     [Linux USB Devel]     [Linux Coverity]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Yosemite Backpacking]
  Powered by Linux