Re: [PATCH v3] PCI: mediatek-gen3: Fix refcount leak in mtk_pcie_init_irq_domains

Bjorn Helgaas
2022-06-08T21:22:11Z

On Wed, Jun 01, 2022 at 08:12:58AM +0400, Miaoqian Lin wrote:
> of_get_child_by_name() returns a node pointer with refcount
> incremented, we should use of_node_put() on it when not need anymore.
> Add missing of_node_put() to avoid refcount leak.
>
> Fixes: 814cceebba9b ("PCI: mediatek-gen3: Add INTx support")
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>

Can we get an ack from Ryder or Jianjun, as well, since they're listed
as maintainers?

> ---
> changes in v2:
> - move of_node_put(intc_node) right after irq_domain_add_linear to cover
> normal path and error paths.
> ---
> changes in v3:
> - call of_node_put() in error paths with goto, and call of_node_put() before
> return 0 in normal path. Since this function has a goto part to handle
> resources, so put them together, as suggested by Miles Chen <miles.chen@mediatek.com>
>
> v1 link: https://lore.kernel.org/all/20220526110246.53502-1-linmq006@gmail.com/
> v2 link: https://lore.kernel.org/all/20220530064807.34534-1-linmq006@gmail.com/
> ---
> drivers/pci/controller/pcie-mediatek-gen3.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
> index 3e8d70bfabc6..bceed28446ed 100644
> --- a/drivers/pci/controller/pcie-mediatek-gen3.c
> +++ b/drivers/pci/controller/pcie-mediatek-gen3.c
> @@ -600,7 +600,8 @@ static int mtk_pcie_init_irq_domains(struct mtk_gen3_pcie *pcie)
> &intx_domain_ops, pcie);
> if (!pcie->intx_domain) {
> dev_err(dev, "failed to create INTx IRQ domain\n");
> - return -ENODEV;
> + ret = -ENODEV;
> + goto out_put_node;
> }
>
> /* Setup MSI */
> @@ -623,13 +624,15 @@ static int mtk_pcie_init_irq_domains(struct mtk_gen3_pcie *pcie)
> goto err_msi_domain;
> }
>
> + of_node_put(intc_node);
> return 0;
>
> err_msi_domain:
> irq_domain_remove(pcie->msi_bottom_domain);
> err_msi_bottom_domain:
> irq_domain_remove(pcie->intx_domain);
> -
> +out_put_node:
> + of_node_put(intc_node);
> return ret;
> }
>
> --
> 2.25.1
>
>
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