drivers/counter/counter-core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
After device_initialize(), the lifetime of the embedded struct device
is expected to be managed through the device core reference counting.
In counter_alloc(), if dev_set_name() fails after device_initialize(),
the error path removes the chrdev, frees the ID, and frees the backing
allocation directly instead of releasing the device reference with
put_device(). This bypasses the normal device lifetime rules and may
leave the reference count of the embedded struct device unbalanced,
resulting in a refcount leak.
The issue was identified by a static analysis tool I developed and
confirmed by manual review.
Fix this by using put_device() in the dev_set_name() failure path and
let counter_device_release() handle the final cleanup.
Fixes: 4da08477ea1f ("counter: Set counter device name")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
---
drivers/counter/counter-core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/counter/counter-core.c b/drivers/counter/counter-core.c
index 50bd30ba3d03..0b1dac61b7b5 100644
--- a/drivers/counter/counter-core.c
+++ b/drivers/counter/counter-core.c
@@ -124,7 +124,8 @@ struct counter_device *counter_alloc(size_t sizeof_priv)
err_dev_set_name:
- counter_chrdev_remove(counter);
+ put_device(dev);
+ return NULL;
err_chrdev_add:
ida_free(&counter_ida, dev->id);
--
2.43.0
On Mon, 13 Apr 2026 21:46:04 +0800, Guangshuo Li wrote:
> After device_initialize(), the lifetime of the embedded struct device
> is expected to be managed through the device core reference counting.
>
> In counter_alloc(), if dev_set_name() fails after device_initialize(),
> the error path removes the chrdev, frees the ID, and frees the backing
> allocation directly instead of releasing the device reference with
> put_device(). This bypasses the normal device lifetime rules and may
> leave the reference count of the embedded struct device unbalanced,
> resulting in a refcount leak.
>
> [...]
Applied, thanks!
[1/1] counter: Fix refcount leak in counter_alloc() error path
commit: d9eeb0ea0d2de658663bfaa9c26eccdd8fd64440
Best regards,
--
William Breathitt Gray <wbg@kernel.org>
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