usb: gadget: pch_udc: Check if driver is present before calling ->setup()

Since we have a separate routine for VBUS sense, the interrupt may occur
before gadget driver is present. Hence, ->setup() call may oops the kernel:

[   55.245843] BUG: kernel NULL pointer dereference, address: 00000010
...
[   55.245843] EIP: pch_udc_isr.cold+0x162/0x33f
...
[   55.245843]  <IRQ>
[   55.245843]  ? pch_udc_svc_data_out+0x160/0x160

Check if driver is present before calling ->setup().

Fixes: f646cf9452 ("USB device driver of Topcliff PCH")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210323153626.54908-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Andy Shevchenko 2021-03-23 17:36:21 +02:00 committed by Greg Kroah-Hartman
parent 91356fed6a
commit fbdbbe6d3e
1 changed files with 18 additions and 10 deletions
drivers/usb/gadget/udc

View File

@ -2298,6 +2298,21 @@ static void pch_udc_svc_data_out(struct pch_udc_dev *dev, int ep_num)
pch_udc_set_dma(dev, DMA_DIR_RX);
}
static int pch_udc_gadget_setup(struct pch_udc_dev *dev)
__must_hold(&dev->lock)
{
int rc;
/* In some cases we can get an interrupt before driver gets setup */
if (!dev->driver)
return -ESHUTDOWN;
spin_unlock(&dev->lock);
rc = dev->driver->setup(&dev->gadget, &dev->setup_data);
spin_lock(&dev->lock);
return rc;
}
/**
* pch_udc_svc_control_in() - Handle Control IN endpoint interrupts
* @dev: Reference to the device structure
@ -2369,15 +2384,12 @@ static void pch_udc_svc_control_out(struct pch_udc_dev *dev)
dev->gadget.ep0 = &dev->ep[UDC_EP0IN_IDX].ep;
else /* OUT */
dev->gadget.ep0 = &ep->ep;
spin_lock(&dev->lock);
/* If Mass storage Reset */
if ((dev->setup_data.bRequestType == 0x21) &&
(dev->setup_data.bRequest == 0xFF))
dev->prot_stall = 0;
/* call gadget with setup data received */
setup_supported = dev->driver->setup(&dev->gadget,
&dev->setup_data);
spin_unlock(&dev->lock);
setup_supported = pch_udc_gadget_setup(dev);
if (dev->setup_data.bRequestType & USB_DIR_IN) {
ep->td_data->status = (ep->td_data->status &
@ -2625,9 +2637,7 @@ static void pch_udc_svc_intf_interrupt(struct pch_udc_dev *dev)
dev->ep[i].halted = 0;
}
dev->stall = 0;
spin_unlock(&dev->lock);
dev->driver->setup(&dev->gadget, &dev->setup_data);
spin_lock(&dev->lock);
pch_udc_gadget_setup(dev);
}
/**
@ -2662,9 +2672,7 @@ static void pch_udc_svc_cfg_interrupt(struct pch_udc_dev *dev)
dev->stall = 0;
/* call gadget zero with setup data received */
spin_unlock(&dev->lock);
dev->driver->setup(&dev->gadget, &dev->setup_data);
spin_lock(&dev->lock);
pch_udc_gadget_setup(dev);
}
/**