Re: [PATCH] usb: gadget: f_ncm: fix wrong usb_ep

From: Peter Chen
Date: Sun Nov 24 2019 - 23:20:56 EST


On 19-11-21 12:18:57, Henry Lin wrote:
> Gadget driver should always use config_ep_by_speed() to initialize
> usb_ep struct according to usb device's operating speed. Otherwise,
> usb_ep struct may be wrong if usb devcie's operating speed is changed.
>

Would you please share the use case how to reproduce it?

Peter
> Signed-off-by: Henry Lin <henryl@xxxxxxxxxx>
> ---
> drivers/usb/gadget/function/f_ncm.c | 28 ++++++++++++----------------
> 1 file changed, 12 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/usb/gadget/function/f_ncm.c b/drivers/usb/gadget/function/f_ncm.c
> index 2d6e76e4cffa..420b9c96f2fe 100644
> --- a/drivers/usb/gadget/function/f_ncm.c
> +++ b/drivers/usb/gadget/function/f_ncm.c
> @@ -870,11 +870,10 @@ static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
> DBG(cdev, "reset ncm control %d\n", intf);
> usb_ep_disable(ncm->notify);
>
> - if (!(ncm->notify->desc)) {
> - DBG(cdev, "init ncm ctrl %d\n", intf);
> - if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
> - goto fail;
> - }
> + DBG(cdev, "init ncm ctrl %d\n", intf);
> + if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
> + goto fail;
> +
> usb_ep_enable(ncm->notify);
>
> /* Data interface has two altsettings, 0 and 1 */
> @@ -897,17 +896,14 @@ static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
> if (alt == 1) {
> struct net_device *net;
>
> - if (!ncm->port.in_ep->desc ||
> - !ncm->port.out_ep->desc) {
> - DBG(cdev, "init ncm\n");
> - if (config_ep_by_speed(cdev->gadget, f,
> - ncm->port.in_ep) ||
> - config_ep_by_speed(cdev->gadget, f,
> - ncm->port.out_ep)) {
> - ncm->port.in_ep->desc = NULL;
> - ncm->port.out_ep->desc = NULL;
> - goto fail;
> - }
> + DBG(cdev, "init ncm\n");
> + if (config_ep_by_speed(cdev->gadget, f,
> + ncm->port.in_ep) ||
> + config_ep_by_speed(cdev->gadget, f,
> + ncm->port.out_ep)) {
> + ncm->port.in_ep->desc = NULL;
> + ncm->port.out_ep->desc = NULL;
> + goto fail;
> }
>
> /* TODO */
> --
> 2.17.1
>

--

Thanks,
Peter Chen