diff mbox series

[v2] usbip: vhci_hcd: fix calling usb_hcd_giveback_urb() with irqs enabled

Message ID 20201006223914.39257-1-skhan@linuxfoundation.org
State Superseded
Headers show
Series [v2] usbip: vhci_hcd: fix calling usb_hcd_giveback_urb() with irqs enabled | expand

Commit Message

Shuah Khan Oct. 6, 2020, 10:39 p.m. UTC
kcov testing uncovered call to usb_hcd_giveback_urb() without disabling
interrupts.

Link: https://lore.kernel.org/linux-usb/CAAeHK+wb4k-LGTjK9F5YbJNviF_+yU+wE_=Vpo9Rn7KFN8vG6Q@mail.gmail.com/

usb_hcd_giveback_urb() is called from vhci's urb_enqueue, when it
determines it doesn't need to xmit the urb and can give it back.
This path runs in task context.

Disable irqs around usb_hcd_giveback_urb() call.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
---

Changes in v2: Changelog updated with correct information.
 drivers/usb/usbip/vhci_hcd.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

Andrey Konovalov Oct. 6, 2020, 11:16 p.m. UTC | #1
On Wed, Oct 7, 2020 at 12:39 AM Shuah Khan <skhan@linuxfoundation.org> wrote:
>

> kcov testing uncovered call to usb_hcd_giveback_urb() without disabling

> interrupts.

>

> Link: https://lore.kernel.org/linux-usb/CAAeHK+wb4k-LGTjK9F5YbJNviF_+yU+wE_=Vpo9Rn7KFN8vG6Q@mail.gmail.com/

>

> usb_hcd_giveback_urb() is called from vhci's urb_enqueue, when it

> determines it doesn't need to xmit the urb and can give it back.

> This path runs in task context.

>

> Disable irqs around usb_hcd_giveback_urb() call.

>

> Reported-by: Andrey Konovalov <andreyknvl@google.com>

> Suggested-by: Alan Stern <stern@rowland.harvard.edu>

> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


Acked-by: Andrey Konovalov <andreyknvl@google.com>


Thank you!

> ---

>

> Changes in v2: Changelog updated with correct information.

>  drivers/usb/usbip/vhci_hcd.c | 8 +++++++-

>  1 file changed, 7 insertions(+), 1 deletion(-)

>

> diff --git a/drivers/usb/usbip/vhci_hcd.c b/drivers/usb/usbip/vhci_hcd.c

> index 1b598db5d8b9..66cde5e5f796 100644

> --- a/drivers/usb/usbip/vhci_hcd.c

> +++ b/drivers/usb/usbip/vhci_hcd.c

> @@ -797,8 +797,14 @@ static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag

>         usb_hcd_unlink_urb_from_ep(hcd, urb);

>  no_need_unlink:

>         spin_unlock_irqrestore(&vhci->lock, flags);

> -       if (!ret)

> +       if (!ret) {

> +               /* usb_hcd_giveback_urb() should be called with

> +                * irqs disabled

> +                */

> +               local_irq_disable();

>                 usb_hcd_giveback_urb(hcd, urb, urb->status);

> +               local_irq_enable();

> +       }

>         return ret;

>  }

>

> --

> 2.25.1

>
diff mbox series

Patch

diff --git a/drivers/usb/usbip/vhci_hcd.c b/drivers/usb/usbip/vhci_hcd.c
index 1b598db5d8b9..66cde5e5f796 100644
--- a/drivers/usb/usbip/vhci_hcd.c
+++ b/drivers/usb/usbip/vhci_hcd.c
@@ -797,8 +797,14 @@  static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag
 	usb_hcd_unlink_urb_from_ep(hcd, urb);
 no_need_unlink:
 	spin_unlock_irqrestore(&vhci->lock, flags);
-	if (!ret)
+	if (!ret) {
+		/* usb_hcd_giveback_urb() should be called with
+		 * irqs disabled
+		 */
+		local_irq_disable();
 		usb_hcd_giveback_urb(hcd, urb, urb->status);
+		local_irq_enable();
+	}
 	return ret;
 }