On Wed, Aug 26, 2020 at 06:53:37AM -0700, [email protected] wrote:
> From: Tom Rix <[email protected]>
>
> clang static analysis flags this error
>
> rtsx_usb.c:505:10: warning: The left operand of '&'
> is a garbage value
> if (val & cd_mask[card])
> ~~~ ^
>
> val is set when rtsx_usb_get_card_status() is successful. The
> problem is how it checks its callers returns.
>
> /* usb_control_msg may return positive when success */
> if (ret < 0)
> return ret;
>
> This is correct for the usb_control_msg() the call. However,
> the call to rtsx_usb_get_status_with_bulk is only successful
> when 0 is returned.
>
> So make status checking block specific.
>
> Fixes: 730876be2566 ("mfd: Add realtek USB card reader driver")
> Signed-off-by: Tom Rix <[email protected]>
> ---
> drivers/misc/cardreader/rtsx_usb.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/misc/cardreader/rtsx_usb.c
> b/drivers/misc/cardreader/rtsx_usb.c
> index 59eda55d92a3..bd392b0c66af 100644
> --- a/drivers/misc/cardreader/rtsx_usb.c
> +++ b/drivers/misc/cardreader/rtsx_usb.c
> @@ -304,14 +304,15 @@ int rtsx_usb_get_card_status(struct rtsx_ucr *ucr, u16
> *status)
> *status = *buf;
>
> kfree(buf);
> +
> + /* usb_control_msg may return positive when success */
it _WILL_ return positive. it will return negative for an error. It
will never return 0.
> + if (ret < 0)
> + return ret;
> } else {
> ret = rtsx_usb_get_status_with_bulk(ucr, status);
> + if (ret)
> + return ret;
> }
> -
> - /* usb_control_msg may return positive when success */
> - if (ret < 0)
> - return ret;
> -
I fail to see how this code is incorrect today.
Well, I do see a bug in here, but you aren't fixing it (short read is
not checked), see the recent linux-usb@vger mail thread about that
problem that we will be fixing tree-wide over time soon...
How can your move of these lines modify anything?
thanks,
greg k-h
