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

From: Chenghai Huang
Date: Fri Aug 22 2025 - 06:39:59 EST


From: Wenkai Lin <linwenkai6@xxxxxxxxxxxxx>

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@xxxxxxxxxxxxx>
Signed-off-by: Chenghai Huang <huangchenghai2@xxxxxxxxxx>
---
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