WUSB: fix oops when completing URBs for disconnected devices

Fix an oops in wusbhc_giveback_urb() if the wusb device had disconnected
while an urb was in progress. Also release the ref count obtained here.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 6 insertions, 2 deletions

diff --git a/drivers/usb/wusbcore/devconnect.c b/drivers/usb/wusbcore/devconnect.c
index 63f200e4efb1..4ac4300a3f9a 100644
--- a/drivers/usb/wusbcore/devconnect.c
+++ b/drivers/usb/wusbcore/devconnect.c
@@ -267,6 +267,8 @@ static void wusbhc_devconnect_acked_work(struct work_struct *work)
         mutex_lock(&wusbhc->mutex);
         wusbhc_devconnect_acked(wusbhc, wusb_dev);
         mutex_unlock(&wusbhc->mutex);
+
+        wusb_dev_put(wusb_dev);
 }
 
 /*
diff --git a/drivers/usb/wusbcore/wusbhc.c b/drivers/usb/wusbcore/wusbhc.c
index 07c63a31c799..3638cc68529f 100644
--- a/drivers/usb/wusbcore/wusbhc.c
+++ b/drivers/usb/wusbcore/wusbhc.c
@@ -339,13 +339,15 @@ void wusbhc_giveback_urb(struct wusbhc *wusbhc, struct urb *urb, int status)
 {
         struct wusb_dev *wusb_dev = __wusb_dev_get_by_usb_dev(wusbhc, urb->dev);
 
-        if (status == 0) {
+        if (status == 0 && wusb_dev) {
                 wusb_dev->entry_ts = jiffies;
 
-                /* wusbhc_devconnect_acked() can't be called from from
+                /* wusbhc_devconnect_acked() can't be called from
                    atomic context so defer it to a work queue. */
                 if (!list_empty(&wusb_dev->cack_node))
                         queue_work(wusbd, &wusb_dev->devconnect_acked_work);
+                else
+                        wusb_dev_put(wusb_dev);
         }
 
         usb_hcd_giveback_urb(&wusbhc->usb_hcd, urb, status);