USB: fix missing error check in probing

usb: check for IO errors usb_set_interface can return

if they happen while unbinding a flag is set to retry upon probe
if they happen during probe they are handled as probe errors

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 1c976c1..4f86447 100644 (file)
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -239,24 +239,31 @@ static int usb_probe_interface(struct device *dev)
 
                /* Carry out a deferred switch to altsetting 0 */
                if (intf->needs_altsetting0) {
-                       usb_set_interface(udev, intf->altsetting[0].
+                       error = usb_set_interface(udev, intf->altsetting[0].
                                        desc.bInterfaceNumber, 0);
+                       if (error < 0)
+                               goto err;
+
                        intf->needs_altsetting0 = 0;
                }
 
                error = driver->probe(intf, id);
-               if (error) {
-                       mark_quiesced(intf);
-                       intf->needs_remote_wakeup = 0;
-                       intf->condition = USB_INTERFACE_UNBOUND;
-                       usb_cancel_queued_reset(intf);
-               } else
-                       intf->condition = USB_INTERFACE_BOUND;
+               if (error)
+                       goto err;
 
+               intf->condition = USB_INTERFACE_BOUND;
                usb_autosuspend_device(udev);
        }
 
        return error;
+
+err:
+       mark_quiesced(intf);
+       intf->needs_remote_wakeup = 0;
+       intf->condition = USB_INTERFACE_UNBOUND;
+       usb_cancel_queued_reset(intf);
+       usb_autosuspend_device(udev);
+       return error;
 }
 
 /* called from driver core with dev locked */
@@ -265,7 +272,7 @@ static int usb_unbind_interface(struct device *dev)
        struct usb_driver *driver = to_usb_driver(dev->driver);
        struct usb_interface *intf = to_usb_interface(dev);
        struct usb_device *udev;
-       int error;
+       int error, r;
 
        intf->condition = USB_INTERFACE_UNBINDING;
 
@@ -293,11 +300,14 @@ static int usb_unbind_interface(struct device *dev)
                 * Just re-enable it without affecting the endpoint toggles.
                 */
                usb_enable_interface(udev, intf, false);
-       } else if (!error && intf->dev.power.status == DPM_ON)
-               usb_set_interface(udev, intf->altsetting[0].
+       } else if (!error && intf->dev.power.status == DPM_ON) {
+               r = usb_set_interface(udev, intf->altsetting[0].
                                desc.bInterfaceNumber, 0);
-       else
+               if (r < 0)
+                       intf->needs_altsetting0 = 1;
+       } else {
                intf->needs_altsetting0 = 1;
+       }
        usb_set_intfdata(intf, NULL);
 
        intf->condition = USB_INTERFACE_UNBOUND;