From f770fbec4165b1acfabdeadb01ad6008d2c537b5 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Fri, 21 Aug 2020 10:55:45 +0800 Subject: USB: UDC: net2280: Fix memory leaks As Anton and Evgeny have noted, the net2280 UDC driver has a problem with leaking memory along some of its failure pathways. It also has another problem, not previously noted, in that some of the failure pathways will call usb_del_gadget_udc() without first calling usb_add_gadget_udc_release(). And it leaks memory by calling kfree() when it should call put_device(). Previous attempts to fix the problems have failed because of lack of support in the UDC core for separately initializing and adding gadgets, or for separately deleting and freeing gadgets. The previous patch in this series adds the necessary support, making it possible to fix the outstanding problems properly. This patch adds an "added" flag to the net2280 structure to indicate whether or not the gadget has been registered (and thus whether or not to call usb_del_gadget()), and it fixes the deallocation issues by calling usb_put_gadget() at the appropriate point. A similar memory leak issue, apparently never before recognized, stems from the fact that the driver never initializes the drvdata field in the gadget's embedded struct device! Evidently this wasn't noticed because the pointer is only ever used as an argument to kfree(), which doesn't mind getting called with a NULL pointer. In fact, the drvdata for gadget device will be written by usb_composite_dev structure if any gadget class is loaded, so it needs to use usb_gadget structure to get net2280 private data. CC: Benjamin Herrenschmidt Reported-by: Anton Vasilyev Reported-by: Evgeny Novikov Reviewed-by: Greg Kroah-Hartman Signed-off-by: Alan Stern Signed-off-by: Peter Chen Signed-off-by: Felipe Balbi --- drivers/usb/gadget/udc/net2280.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'drivers/usb/gadget/udc/net2280.c') diff --git a/drivers/usb/gadget/udc/net2280.c b/drivers/usb/gadget/udc/net2280.c index 7530bd9a08c4..d50bc6e19f2a 100644 --- a/drivers/usb/gadget/udc/net2280.c +++ b/drivers/usb/gadget/udc/net2280.c @@ -3561,7 +3561,7 @@ static irqreturn_t net2280_irq(int irq, void *_dev) static void gadget_release(struct device *_dev) { - struct net2280 *dev = dev_get_drvdata(_dev); + struct net2280 *dev = container_of(_dev, struct net2280, gadget.dev); kfree(dev); } @@ -3572,7 +3572,8 @@ static void net2280_remove(struct pci_dev *pdev) { struct net2280 *dev = pci_get_drvdata(pdev); - usb_del_gadget_udc(&dev->gadget); + if (dev->added) + usb_del_gadget(&dev->gadget); BUG_ON(dev->driver); @@ -3603,6 +3604,7 @@ static void net2280_remove(struct pci_dev *pdev) device_remove_file(&pdev->dev, &dev_attr_registers); ep_info(dev, "unbind\n"); + usb_put_gadget(&dev->gadget); } /* wrap this driver around the specified device, but @@ -3624,6 +3626,7 @@ static int net2280_probe(struct pci_dev *pdev, const struct pci_device_id *id) } pci_set_drvdata(pdev, dev); + usb_initialize_gadget(&pdev->dev, &dev->gadget, gadget_release); spin_lock_init(&dev->lock); dev->quirks = id->driver_data; dev->pdev = pdev; @@ -3774,10 +3777,10 @@ static int net2280_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (retval) goto done; - retval = usb_add_gadget_udc_release(&pdev->dev, &dev->gadget, - gadget_release); + retval = usb_add_gadget(&dev->gadget); if (retval) goto done; + dev->added = 1; return 0; done: -- cgit v1.2.3-59-g8ed1b