[PATCH] samples/vfio-mdev: don't return zero on failure paths in mtty_dev_init()

From: Alexey Khoroshilov
Date: Fri Dec 30 2016 - 17:41:14 EST


If class_create() or mdev_register_device() fail, mtty_dev_init()
breaks off initialization, deallocates all resources, but returns zero.

The patch adds proper error code return values.

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

Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>
---
samples/vfio-mdev/mtty.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index 6b633a4ea333..e9c52e1f97a6 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -1446,6 +1446,7 @@ static int __init mtty_dev_init(void)
mtty_dev.vd_class = class_create(THIS_MODULE, MTTY_CLASS_NAME);

if (IS_ERR(mtty_dev.vd_class)) {
+ ret = PTR_ERR(mtty_dev.vd_class);
pr_err("Error: failed to register mtty_dev class\n");
goto failed1;
}
@@ -1458,7 +1459,8 @@ static int __init mtty_dev_init(void)
if (ret)
goto failed2;

- if (mdev_register_device(&mtty_dev.dev, &mdev_fops) != 0)
+ ret = mdev_register_device(&mtty_dev.dev, &mdev_fops);
+ if (ret)
goto failed3;

mutex_init(&mdev_list_lock);
@@ -1467,11 +1469,9 @@ static int __init mtty_dev_init(void)
goto all_done;

failed3:
-
device_unregister(&mtty_dev.dev);
failed2:
class_destroy(mtty_dev.vd_class);
-
failed1:
cdev_del(&mtty_dev.vd_cdev);
unregister_chrdev_region(mtty_dev.vd_devt, MINORMASK);
--
2.7.4