[PATCH 2/4] USB: make to_usb_device_driver() use container_of_const()

[Greg Kroah-Hartman]

Turns out that we have some const pointers being passed to
to_usb_device_driver() but were not catching this.  Change the macro to
properly propagate the const-ness of the pointer so that we will notice
when we try to write to memory that we shouldn't be writing to.

This requires fixing up the usb_driver_applicable() function as well,
because it can handle a const * to struct usb_driver.

Cc: Johan Hovold <johan@xxxxxxxxxx>
Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Cc: Grant Grundler <grundler@xxxxxxxxxxxx>
Cc: Yajun Deng <yajun.deng@xxxxxxxxx>
Cc: Oliver Neukum <oneukum@xxxxxxxx>
Cc: Douglas Anderson <dianders@xxxxxxxxxxxx>
Cc: linux-usb@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/core/driver.c | 4 ++--
 drivers/usb/core/usb.h    | 2 +-
 include/linux/usb.h       | 3 +--
 3 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index c985a272e552..d0fb2f315d65 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -840,7 +840,7 @@ const struct usb_device_id *usb_device_match_id(struct usb_device *udev,
 EXPORT_SYMBOL_GPL(usb_device_match_id);
 
 bool usb_driver_applicable(struct usb_device *udev,
-			   struct usb_device_driver *udrv)
+			   const struct usb_device_driver *udrv)
 {
 	if (udrv->id_table && udrv->match)
 		return usb_device_match_id(udev, udrv->id_table) != NULL &&
@@ -860,7 +860,7 @@ static int usb_device_match(struct device *dev, const struct device_driver *drv)
 	/* devices and interfaces are handled separately */
 	if (is_usb_device(dev)) {
 		struct usb_device *udev;
-		struct usb_device_driver *udrv;
+		const struct usb_device_driver *udrv;
 
 		/* interface drivers never match devices */
 		if (!is_usb_device_driver(drv))
diff --git a/drivers/usb/core/usb.h b/drivers/usb/core/usb.h
index b8324ea05b20..a9b37aeb515b 100644
--- a/drivers/usb/core/usb.h
+++ b/drivers/usb/core/usb.h
@@ -75,7 +75,7 @@ extern int usb_match_device(struct usb_device *dev,
 extern const struct usb_device_id *usb_device_match_id(struct usb_device *udev,
 				const struct usb_device_id *id);
 extern bool usb_driver_applicable(struct usb_device *udev,
-				  struct usb_device_driver *udrv);
+				  const struct usb_device_driver *udrv);
 extern void usb_forced_unbind_intf(struct usb_interface *intf);
 extern void usb_unbind_and_rebind_marked_interfaces(struct usb_device *udev);
 
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 4390426973f4..5c619e8240fe 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -1283,8 +1283,7 @@ struct usb_device_driver {
 	unsigned int supports_autosuspend:1;
 	unsigned int generic_subclass:1;
 };
-#define	to_usb_device_driver(d) container_of(d, struct usb_device_driver, \
-		driver)
+#define	to_usb_device_driver(d) container_of_const(d, struct usb_device_driver, driver)
 
 /**
  * struct usb_class_driver - identifies a USB driver that wants to use the USB major number
-- 
2.45.2