usb: fix reference leak in usb_new_device()

When device_add(&udev->dev) succeeds and a later call fails,
usb_new_device() does not properly call device_del(). As comment of
device_add() says, 'if device_add() succeeds, you should call
device_del() when you want to get rid of it. If device_add() has not
succeeded, use only put_device() to drop the reference count'.

Found by code review.

Cc: stable <stable@kernel.org>
Fixes: 9f8b17e643fe ("USB: make usbdevices export their device nodes instead of using a separate class")
Signed-off-by: Ma Ke <make_ruc2021@163.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20241218071346.2973980-1-make_ruc2021@163.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 4b93c0bd1d4bcc8141ca34c490f67e2a368c1902..21ac9b464696f561c87b56eab4b4dce7c5e64533 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2663,13 +2663,13 @@ int usb_new_device(struct usb_device *udev)
                err = sysfs_create_link(&udev->dev.kobj,
                                &port_dev->dev.kobj, "port");
                if (err)
-                       goto fail;
+                       goto out_del_dev;
 
                err = sysfs_create_link(&port_dev->dev.kobj,
                                &udev->dev.kobj, "device");
                if (err) {
                        sysfs_remove_link(&udev->dev.kobj, "port");
-                       goto fail;
+                       goto out_del_dev;
                }
 
                if (!test_and_set_bit(port1, hub->child_usage_bits))
@@ -2683,6 +2683,8 @@ int usb_new_device(struct usb_device *udev)
        pm_runtime_put_sync_autosuspend(&udev->dev);
        return err;
 
+out_del_dev:
+       device_del(&udev->dev);
 fail:
        usb_set_device_state(udev, USB_STATE_NOTATTACHED);
        pm_runtime_disable(&udev->dev);