[PATCH 4.3 16/55] USB: host: ohci-at91: fix a crash in ohci_hcd_at91_overcurrent_irq

From: Greg Kroah-Hartman
Date: Wed Jan 20 2016 - 19:56:43 EST


4.3-stable review patch. If anyone has any objections, please let me know.

------------------

From: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>

commit 4a0c4c36094cefd85cbe489590382ef69516ccef upstream.

The interrupt handler, ohci_hcd_at91_overcurrent_irq may be called right
after registration. At that time, pdev->dev.platform_data is not yet set,
leading to a NULL pointer dereference.

Fixes: e4df92279fd9 (USB: host: ohci-at91: merge loops in ohci_hcd_at91_drv_probe)
Reported-by: Peter Rosin <peda@xxxxxxxxxx>
Tested-by: Peter Rosin <peda@xxxxxxxxxx>
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/host/ohci-at91.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

--- a/drivers/usb/host/ohci-at91.c
+++ b/drivers/usb/host/ohci-at91.c
@@ -473,6 +473,8 @@ static int ohci_hcd_at91_drv_probe(struc
if (!pdata)
return -ENOMEM;

+ pdev->dev.platform_data = pdata;
+
if (!of_property_read_u32(np, "num-ports", &ports))
pdata->ports = ports;

@@ -483,6 +485,7 @@ static int ohci_hcd_at91_drv_probe(struc
*/
if (i >= pdata->ports) {
pdata->vbus_pin[i] = -EINVAL;
+ pdata->overcurrent_pin[i] = -EINVAL;
continue;
}

@@ -513,10 +516,8 @@ static int ohci_hcd_at91_drv_probe(struc
}

at91_for_each_port(i) {
- if (i >= pdata->ports) {
- pdata->overcurrent_pin[i] = -EINVAL;
- continue;
- }
+ if (i >= pdata->ports)
+ break;

pdata->overcurrent_pin[i] =
of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
@@ -552,8 +553,6 @@ static int ohci_hcd_at91_drv_probe(struc
}
}

- pdev->dev.platform_data = pdata;
-
device_init_wakeup(&pdev->dev, 1);
return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
}