Re: [PATCH v3 2/2] PCI: of_property: Omit 'bus-range' property if no secondary bus

[Manivannan Sadhasivam]

On Mon, Mar 24, 2025 at 05:01:08PM +0800, Bo Sun wrote:
> The previous implementation of of_pci_add_properties() and
> of_pci_prop_bus_range() assumed that a valid secondary bus is always
> present, which can be problematic in cases where no bus numbers are
> assigned for a secondary bus. This patch introduces a check for a valid
> secondary bus and omits the 'bus-range' property if it is not available,
> preventing dereferencing the NULL pointer.
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 407d1a51921e ("PCI: Create device tree node for bridge")
> Suggested-by: Bjorn Helgaas <helgaas@xxxxxxxxxx>
> Signed-off-by: Bo Sun <Bo.Sun.CN@xxxxxxxxxxxxx>

Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>

- Mani

> ---
> v3: Add 'Fixes' tag as requested by Mani. 
> 
>  drivers/pci/of_property.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/pci/of_property.c b/drivers/pci/of_property.c
> index 58fbafac7c6a..792b0163af45 100644
> --- a/drivers/pci/of_property.c
> +++ b/drivers/pci/of_property.c
> @@ -91,6 +91,9 @@ static int of_pci_prop_bus_range(struct pci_dev *pdev,
>  				 struct of_changeset *ocs,
>  				 struct device_node *np)
>  {
> +	if (!pdev->subordinate)
> +		return -EINVAL;
> +
>  	u32 bus_range[] = { pdev->subordinate->busn_res.start,
>  			    pdev->subordinate->busn_res.end };
>  
> -- 
> 2.49.0
> 

-- 
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