Messages in this thread | | | Date | Wed, 26 Jan 2022 10:49:10 +0100 | From | Greg KH <> | Subject | Re: [PATCH -next] xhci: fix two places when dealing with return value of function xhci_check_args |
| |
On Wed, Jan 26, 2022 at 05:41:26PM +0800, Hongyu Xie wrote: > From: Hongyu Xie <xiehongyu1@kylinos.cn> > > xhci_check_args returns 4 types of value, -ENODEV, -EINVAL, 1 and 0. > xhci_urb_enqueue and xhci_check_streams_endpoint return -EINVAL if > the return value of xhci_check_args <= 0. > This will cause a problem.
What problem?
> For example, r8152_submit_rx calling usb_submit_urb in > drivers/net/usb/r8152.c. > r8152_submit_rx will never get -ENODEV after submiting an urb > when xHC is halted, > because xhci_urb_enqueue returns -EINVAL in the very beginning. > > Fixes: 203a86613fb3 ("xhci: Avoid NULL pointer deref when host dies.") > Cc: stable@vger.kernel.org > Signed-off-by: Hongyu Xie <xiehongyu1@kylinos.cn> > --- > drivers/usb/host/xhci.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c > index dc357cabb265..a7a55dd206fe 100644 > --- a/drivers/usb/host/xhci.c > +++ b/drivers/usb/host/xhci.c > @@ -1604,9 +1604,12 @@ static int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag > struct urb_priv *urb_priv; > int num_tds; > > - if (!urb || xhci_check_args(hcd, urb->dev, urb->ep, > - true, true, __func__) <= 0) > + if (!urb) > return -EINVAL; > + ret = xhci_check_args(hcd, urb->dev, urb->ep, > + true, true, __func__); > + if (ret <= 0) > + return ret;
So if 0 is returned, you will now return that here, is that ok? That is a change in functionality.
But this can only ever be the case for a root hub, is that ok?
> > slot_id = urb->dev->slot_id; > ep_index = xhci_get_endpoint_index(&urb->ep->desc); > @@ -3323,7 +3326,7 @@ static int xhci_check_streams_endpoint(struct xhci_hcd *xhci, > return -EINVAL; > ret = xhci_check_args(xhci_to_hcd(xhci), udev, ep, 1, true, __func__); > if (ret <= 0) > - return -EINVAL; > + return ret;
Again, this means all is good? Why is this being called for a root hub?
thanks,
greg k-h
| |