driver: uio: fix possible use-after-free in __uio_register_device

In uio_dev_add_attributes() error handing case, idev is used after
device_unregister(), in which 'idev' has been released, touch idev cause
use-after-free.

Fixes: a93e7b3315 ("uio: Prevent device destruction while fds are open")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Reviewed-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Liu Jian 2019-01-23 06:45:38 +08:00 коммит произвёл Greg Kroah-Hartman
Родитель 1a392b3de7
Коммит 221a1f4ac1
1 изменённых файлов: 4 добавлений и 2 удалений

Просмотреть файл

@ -945,6 +945,7 @@ int __uio_register_device(struct module *owner,
return ret;
}
device_initialize(&idev->dev);
idev->dev.devt = MKDEV(uio_major, idev->minor);
idev->dev.class = &uio_class;
idev->dev.parent = parent;
@ -955,7 +956,7 @@ int __uio_register_device(struct module *owner,
if (ret)
goto err_device_create;
ret = device_register(&idev->dev);
ret = device_add(&idev->dev);
if (ret)
goto err_device_create;
@ -987,9 +988,10 @@ int __uio_register_device(struct module *owner,
err_request_irq:
uio_dev_del_attributes(idev);
err_uio_dev_add_attributes:
device_unregister(&idev->dev);
device_del(&idev->dev);
err_device_create:
uio_free_minor(idev);
put_device(&idev->dev);
return ret;
}
EXPORT_SYMBOL_GPL(__uio_register_device);