Re: [PATCH] PCI: xgene: Fix device node reference leak in xgene_pcie_probe()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] pci: xgene: refcount underflow and build failure due to hallucinated of_node_get()
--

commit 3a601f05188e398e03ea9af2fc4238c97e5b4cf2
Author: Wentao Liang <vulab@iscas.ac.cn>

PCI: xgene: Fix device node reference leak in xgene_pcie_probe()

This patch attempts to fix a device node reference leak in the error paths
of xgene_pcie_probe() by adding an error handling label that drops the node
reference.

Cc: stable@vger.kernel.org

> diff --git a/drivers/pci/controller/pci-xgene.c b/drivers/pci/controller/pci-xgene.c
> index 83c9a2930eeca..6b922120db3fc 100644
> --- a/drivers/pci/controller/pci-xgene.c
> +++ b/drivers/pci/controller/pci-xgene.c
[ ... ]
> @@ -630,20 +630,28 @@ static int xgene_pcie_probe(struct platform_device *pdev)
[ ... ]
> -	return pci_host_probe(bridge);
> +	ret = pci_host_probe(bridge);
> +	if (ret)
> +		goto err_put_node;
> +
> +	return 0;
> +
> +err_put_node:
> +	of_node_put(port->node);

[Severity: High]
Does this patch introduce a refcount underflow and a build failure?

The commit message states that xgene_pcie_probe() takes a reference with
of_node_get(), but that function does not appear to be called anywhere within
xgene_pcie_probe(). If there is no prior of_node_get() incrementing the count,
calling of_node_put() on these error paths will drop an unowned reference,
potentially causing a use-after-free of the device node.

Additionally, does struct xgene_pcie contain a node member? It appears this
struct does not have a node field, which means accessing port->node will
cause a build failure.

> +	return ret;
>  }

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Sashiko AI review · https://sashiko.dev/#/patchset/20260917132235.2153154-1-vulab@iscas.ac.cn?part=1