Re: [PATCH] PCI: rcar-gen4: Fix device_node leak in rcar_gen4_pcie_host_msi_addr()

[Marek Vasut <marek.vasut@mailbox.org>]

On 9/18/26 11:10 AM, Fuad Tabba wrote:
> rcar_gen4_pcie_host_msi_addr() calls of_msi_xlate() with *msi_np NULL,
> so it receives the MSI controller node with a reference held, and every
> return past the NULL check leaks that reference, the success path
> included. Declare msi_node with __free(device_node) so it's put on
> every return.
> 
> Fixes: 8d6af27c0a73 ("PCI: rcar-gen4: Configure AXIINTC if iMSI-RX is not used")
> Reported-by: Sashiko <sashiko-bot@kernel.org>
> Closes: https://lore.kernel.org/linux-pci/20260905213855.8D6671F00A3D@smtp.kernel.org/
> Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev>
> ---
>   drivers/pci/controller/dwc/pcie-rcar-gen4.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index fbe465a29068f..d61ce802b4614 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -323,7 +323,7 @@ static struct rcar_gen4_pcie *rcar_gen4_pcie_alloc(struct platform_device *pdev)
>   static int rcar_gen4_pcie_host_msi_addr(struct dw_pcie_rp *pp, u32 *msi_addr)
>   {
>   	struct dw_pcie *dw = to_dw_pcie_from_pp(pp);
> -	struct device_node *msi_node = NULL;
> +	struct device_node *msi_node __free(device_node) = NULL;
I think you have to call of_node_put() on msi_node(), so what about this 
instead ?

"
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c 
b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index 8057c31c0123a..2eb20cff2fcad 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -382,20 +382,29 @@ static int rcar_gen4_pcie_host_msi_addr(struct 
dw_pcie_rp *pp, u32 *msi_addr)
  		return -ENODEV;

  	/* Check if "msi-parent" or the "msi-map" points to ARM GICv3 ITS. */
-	if (!of_device_is_compatible(msi_node, "arm,gic-v3-its"))
-		return dev_err_probe(dev, -ENODEV, "Compatible MSI controller not 
found\n");
+	if (!of_device_is_compatible(msi_node, "arm,gic-v3-its")) {
+		ret = dev_err_probe(dev, -ENODEV, "Compatible MSI controller not 
found\n");
+		goto exit;
+	}

  	/* Derive GITS_TRANSLATER address from GICv3 */
  	ret = of_address_to_resource(msi_node, 0, &res);
-	if (ret < 0)
-		return dev_err_probe(dev, ret, "MSI controller resources not 
obtained\n");
+	if (ret < 0) {
+		ret = dev_err_probe(dev, ret, "MSI controller resources not obtained\n");
+		goto exit;
+	}

  	addr = res.start + GITS_TRANSLATER;
-	if (addr >= SZ_4G)
-		return dev_err_probe(dev, -EINVAL, "MSI controller address above 
32bit range\n");
+	if (addr >= SZ_4G) {
+		ret = dev_err_probe(dev, -EINVAL, "MSI controller address above 32bit 
range\n");
+		goto exit;
+	}

  	*msi_addr = addr;
-	return 0;
+
+exit:
+	of_node_put(msi_node);
+	return ret;
  }

  static int rcar_gen4_pcie_host_msi_init(struct dw_pcie_rp *pp)
"

Also, I think drivers/pci/controller/pcie-iproc.c 
iproc_pcie_msi_enable() needs similar fix ?