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