In of_unittest_pci_node_verify(), when the add parameter is false, device_find_any_child() obtains a reference to a child device. This function implicitly calls get_device() to increment the device's reference count before returning the pointer. However, the caller fails to properly release this reference by calling put_device(), leading to a device reference count leak. Add put_device() in the else branch immediately after child_dev is no longer needed.
As the comment of device_find_any_child states: "NOTE: you will need to drop the reference with put_device() after use".
Found by code review.
Cc: stable@vger.kernel.org Fixes: 26409dd04589 ("of: unittest: Add pci_dt_testdrv pci driver") Signed-off-by: Ma Ke make24@iscas.ac.cn --- Changes in v2: - modified the put_device() location as suggestions. --- drivers/of/unittest.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c index e3503ec20f6c..388e9ec2cccf 100644 --- a/drivers/of/unittest.c +++ b/drivers/of/unittest.c @@ -4300,6 +4300,7 @@ static int of_unittest_pci_node_verify(struct pci_dev *pdev, bool add) unittest(!np, "Child device tree node is not removed\n"); child_dev = device_find_any_child(&pdev->dev); unittest(!child_dev, "Child device is not removed\n"); + put_device(child_dev); }
failed:
On Tue, 30 Sep 2025 16:16:18 +0800, Ma Ke wrote:
In of_unittest_pci_node_verify(), when the add parameter is false, device_find_any_child() obtains a reference to a child device. This function implicitly calls get_device() to increment the device's reference count before returning the pointer. However, the caller fails to properly release this reference by calling put_device(), leading to a device reference count leak. Add put_device() in the else branch immediately after child_dev is no longer needed.
As the comment of device_find_any_child states: "NOTE: you will need to drop the reference with put_device() after use".
Found by code review.
Cc: stable@vger.kernel.org Fixes: 26409dd04589 ("of: unittest: Add pci_dt_testdrv pci driver") Signed-off-by: Ma Ke make24@iscas.ac.cn
Changes in v2:
- modified the put_device() location as suggestions.
drivers/of/unittest.c | 1 + 1 file changed, 1 insertion(+)
Applied, thanks!
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