[PATCH 1/4] uacce: fix for cdev memory leak

[Chenghai Huang <huangchenghai2@huawei.com>]

From: Wenkai Lin <linwenkai6@hisilicon.com>

If adding uacce cdev to the system fails, it could be due to two
reasons: either the device's devt exists when the failure occurs,
or the device_add operation fails. In the latter case, cdev_del
will be executed, but in the former case, it will not, leading to a
resource leak. Therefore, it is necessary to perform the cdev_del
action during abnormal exit.

Fixes: 015d239ac014 ("uacce: add uacce driver")
Signed-off-by: Wenkai Lin <linwenkai6@hisilicon.com>
Signed-off-by: Chenghai Huang <huangchenghai2@huawei.com>
---
 drivers/misc/uacce/uacce.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
index 42e7d2a2a90c..3604f722ed60 100644
--- a/drivers/misc/uacce/uacce.c
+++ b/drivers/misc/uacce/uacce.c
@@ -519,6 +519,8 @@ EXPORT_SYMBOL_GPL(uacce_alloc);
  */
 int uacce_register(struct uacce_device *uacce)
 {
+	int ret;
+
 	if (!uacce)
 		return -ENODEV;
 
@@ -529,7 +531,14 @@ int uacce_register(struct uacce_device *uacce)
 	uacce->cdev->ops = &uacce_fops;
 	uacce->cdev->owner = THIS_MODULE;
 
-	return cdev_device_add(uacce->cdev, &uacce->dev);
+	ret = cdev_device_add(uacce->cdev, &uacce->dev);
+	if (ret) {
+		cdev_del(uacce->cdev);
+		uacce->cdev = NULL;
+		return ret;
+	}
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(uacce_register);
 
-- 
2.33.0