[PATCH] [media] mceusb: fix usbdev leak

[PATCH] [media] mceusb: fix usbdev leak

[Alexey Khoroshilov]

mceusb_init_rc_dev() does usb_get_dev(), but there is no any
usb_put_dev() in the driver.

The patch tries to straighten logic. It moves usb_get_dev()
directly to mceusb_dev_probe() and adds usb_put_dev() to an error path
and to mceusb_dev_disconnect().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
---
 drivers/media/rc/mceusb.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/media/rc/mceusb.c b/drivers/media/rc/mceusb.c
index 45b0894288e5..23e532da0cf7 100644
--- a/drivers/media/rc/mceusb.c
+++ b/drivers/media/rc/mceusb.c
@@ -1198,10 +1198,9 @@ static void mceusb_flash_led(struct mceusb_dev *ir)
 	mce_async_out(ir, FLASH_LED, sizeof(FLASH_LED));
 }
 
-static struct rc_dev *mceusb_init_rc_dev(struct mceusb_dev *ir,
-					 struct usb_interface *intf)
+static struct rc_dev *mceusb_init_rc_dev(struct mceusb_dev *ir)
 {
-	struct usb_device *udev = usb_get_dev(interface_to_usbdev(intf));
+	struct usb_device *udev = ir->usbdev;
 	struct device *dev = ir->dev;
 	struct rc_dev *rc;
 	int ret;
@@ -1341,7 +1340,7 @@ static int mceusb_dev_probe(struct usb_interface *intf,
 	if (!ir->urb_in)
 		goto urb_in_alloc_fail;
 
-	ir->usbdev = dev;
+	ir->usbdev = usb_get_dev(dev);
 	ir->dev = &intf->dev;
 	ir->len_in = maxp;
 	ir->flags.microsoft_gen1 = is_microsoft_gen1;
@@ -1362,7 +1361,7 @@ static int mceusb_dev_probe(struct usb_interface *intf,
 		snprintf(name + strlen(name), sizeof(name) - strlen(name),
 			 " %s", buf);
 
-	ir->rc = mceusb_init_rc_dev(ir, intf);
+	ir->rc = mceusb_init_rc_dev(ir);
 	if (!ir->rc)
 		goto rc_dev_fail;
 
@@ -1408,6 +1407,7 @@ static int mceusb_dev_probe(struct usb_interface *intf,
 
 	/* Error-handling path */
 rc_dev_fail:
+	usb_put_dev(ir->usbdev);
 	usb_free_urb(ir->urb_in);
 urb_in_alloc_fail:
 	usb_free_coherent(dev, maxp, ir->buf_in, ir->dma_in);
@@ -1435,6 +1435,7 @@ static void mceusb_dev_disconnect(struct usb_interface *intf)
 	usb_kill_urb(ir->urb_in);
 	usb_free_urb(ir->urb_in);
 	usb_free_coherent(dev, ir->len_in, ir->buf_in, ir->dma_in);
+	usb_put_dev(dev);
 
 	kfree(ir);
 }
-- 
1.9.1

Re: [PATCH] [media] mceusb: fix usbdev leak

[Sean Young]

On Tue, Sep 09, 2014 at 02:10:43AM +0400, Alexey Khoroshilov wrote:
> mceusb_init_rc_dev() does usb_get_dev(), but there is no any
> usb_put_dev() in the driver.

drivers/media/rc/imon.c suffers from the same problem.

Thanks
Sean

Re: [PATCH] [media] mceusb: fix usbdev leak

[Alexey Khoroshilov]

On 09.09.2014 14:39, Sean Young wrote:
> On Tue, Sep 09, 2014 at 02:10:43AM +0400, Alexey Khoroshilov wrote:
>> mceusb_init_rc_dev() does usb_get_dev(), but there is no any
>> usb_put_dev() in the driver.
> drivers/media/rc/imon.c suffers from the same problem.
>
> Thanks
> Sean
Yes, our static analyzers show that as well.

We will prepare a patch soon, if nobody has done it yet.

Thanks,
Alexey

[PATCH] [media] imon: fix usbdev leaks

[Alexey Khoroshilov]

imon_probe() does three usb_get_dev(), but there is no any
usb_put_dev() in the driver.

The patch adds usb_put_dev() to error paths, to imon_disconnect()
and to imon_probe() as far as usbdev is not saved anywhere.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
---
 drivers/media/rc/imon.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/media/rc/imon.c b/drivers/media/rc/imon.c
index 7115e68ba697..06ff61ec3e1e 100644
--- a/drivers/media/rc/imon.c
+++ b/drivers/media/rc/imon.c
@@ -2181,6 +2181,7 @@ idev_setup_failed:
 	usb_kill_urb(ictx->rx_urb_intf0);
 urb_submit_failed:
 find_endpoint_failed:
+	usb_put_dev(ictx->usbdev_intf0);
 	mutex_unlock(&ictx->lock);
 	usb_free_urb(tx_urb);
 tx_urb_alloc_failed:
@@ -2253,6 +2254,7 @@ urb_submit_failed:
 		input_unregister_device(ictx->touch);
 touch_setup_failed:
 find_endpoint_failed:
+	usb_put_dev(ictx->usbdev_intf1);
 	mutex_unlock(&ictx->lock);
 	usb_free_urb(rx_urb);
 rx_urb_alloc_failed:
@@ -2366,11 +2368,13 @@ static int imon_probe(struct usb_interface *interface,
 		 usbdev->bus->busnum, usbdev->devnum);
 
 	mutex_unlock(&driver_lock);
+	usb_put_dev(usbdev);
 
 	return 0;
 
 fail:
 	mutex_unlock(&driver_lock);
+	usb_put_dev(usbdev);
 	dev_err(dev, "unable to register, err %d\n", ret);
 
 	return ret;
@@ -2410,6 +2414,7 @@ static void imon_disconnect(struct usb_interface *interface)
 	if (ifnum == 0) {
 		ictx->dev_present_intf0 = false;
 		usb_kill_urb(ictx->rx_urb_intf0);
+		usb_put_dev(ictx->usbdev_intf0);
 		input_unregister_device(ictx->idev);
 		rc_unregister_device(ictx->rdev);
 		if (ictx->display_supported) {
@@ -2421,6 +2426,7 @@ static void imon_disconnect(struct usb_interface *interface)
 	} else {
 		ictx->dev_present_intf1 = false;
 		usb_kill_urb(ictx->rx_urb_intf1);
+		usb_put_dev(ictx->usbdev_intf1);
 		if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
 			input_unregister_device(ictx->touch);
 			del_timer_sync(&ictx->ttimer);
-- 
1.9.1