From: Alan Stern Date: Tue, 30 Jul 2013 19:18:15 +0000 (-0400) Subject: usb: gadget: fix a bug and a WARN_ON in dummy-hcd X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=5f5610f69be3a925b1f79af27150bb7377bc9ad6;p=linux.git usb: gadget: fix a bug and a WARN_ON in dummy-hcd This patch fixes a NULL pointer dereference and a WARN_ON in dummy-hcd. These things were the result of moving to the UDC core framework, and possibly of changes to that framework. Now unloading a gadget driver causes the UDC to be stopped after the gadget driver is unbound, not before. Therefore the "driver" argument to dummy_udc_stop() can be NULL, so we must not try to print the driver's name without checking first. Also, the UDC framework automatically unregisters the gadget when the UDC is deleted. Therefore a sysfs attribute file attached to the gadget must be removed before the UDC is deleted, not after. Signed-off-by: Alan Stern CC: Signed-off-by: Felipe Balbi --- diff --git a/drivers/usb/gadget/dummy_hcd.c b/drivers/usb/gadget/dummy_hcd.c index 06ecd08fd57a3..b8a2376971a47 100644 --- a/drivers/usb/gadget/dummy_hcd.c +++ b/drivers/usb/gadget/dummy_hcd.c @@ -923,8 +923,9 @@ static int dummy_udc_stop(struct usb_gadget *g, struct dummy_hcd *dum_hcd = gadget_to_dummy_hcd(g); struct dummy *dum = dum_hcd->dum; - dev_dbg(udc_dev(dum), "unregister gadget driver '%s'\n", - driver->driver.name); + if (driver) + dev_dbg(udc_dev(dum), "unregister gadget driver '%s'\n", + driver->driver.name); dum->driver = NULL; @@ -1000,8 +1001,8 @@ static int dummy_udc_remove(struct platform_device *pdev) { struct dummy *dum = platform_get_drvdata(pdev); - usb_del_gadget_udc(&dum->gadget); device_remove_file(&dum->gadget.dev, &dev_attr_function); + usb_del_gadget_udc(&dum->gadget); return 0; }