Re: [PATCH 1/3] usb: gadget: udc: Avoid tasklet passing a global

Kees Cook
2020-07-16T19:42:00Z

On Thu, Jul 16, 2020 at 09:28:23AM +0200, Greg Kroah-Hartman wrote:
> On Wed, Jul 15, 2020 at 08:08:45PM -0700, Kees Cook wrote:
> > There's no reason for the tasklet callback to set an argument since it
> > always uses a global. Instead, use the global directly, in preparation
> > for converting the tasklet subsystem to modern callback conventions.
> >
> > Signed-off-by: Kees Cook <keescook@chromium.org>
> > ---
> > drivers/usb/gadget/udc/snps_udc_core.c | 6 ++----
> > 1 file changed, 2 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/usb/gadget/udc/snps_udc_core.c b/drivers/usb/gadget/udc/snps_udc_core.c
> > index 3fcded31405a..afdd28f332ce 100644
> > --- a/drivers/usb/gadget/udc/snps_udc_core.c
> > +++ b/drivers/usb/gadget/udc/snps_udc_core.c
> > @@ -96,9 +96,7 @@ static int stop_pollstall_timer;
> > static DECLARE_COMPLETION(on_pollstall_exit);
> >
> > /* tasklet for usb disconnect */
> > -static DECLARE_TASKLET(disconnect_tasklet, udc_tasklet_disconnect,
> > - (unsigned long) &udc);
> > -
> > +static DECLARE_TASKLET(disconnect_tasklet, udc_tasklet_disconnect, 0);
> >
> > /* endpoint names used for print */
> > static const char ep0_string[] = "ep0in";
> > @@ -1661,7 +1659,7 @@ static void usb_disconnect(struct udc *dev)
> > /* Tasklet for disconnect to be outside of interrupt context */
> > static void udc_tasklet_disconnect(unsigned long par)
> > {
> > - struct udc *dev = (struct udc *)(*((struct udc **) par));
> > + struct udc *dev = udc;
> > u32 tmp;
> >
> > DBG(dev, "Tasklet disconnect\n");
>
> Feel free to just take this in your tree, no need to wait for the USB
> stuff to land.
>
> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Okay, thanks! I'll carry this series for v5.9, unless I hear otherwise
from Thomas. :)

--
Kees Cook