[PATCH v2] interconnect: imx: fix use-after-free in imx_icc_node_init_qos()

[Frank Li]

On Wed, Apr 08, 2026 at 03:30:22PM +0000, Wentao Liang wrote:
> The function imx_icc_node_init_qos() manually manages the reference count
> of struct device_node *dn using of_node_put(). However, some error paths
> use dn after the put, leading to use-after-free. Convert to automatic
> cleanup using __free(device_node) to ensure the reference is always
> released when dn goes out of scope.
>
> Fixes: f0d8048525d7 ("interconnect: Add imx core driver")
> Cc: stable at vger.kernel.org
> Signed-off-by: Wentao Liang <vulab at iscas.ac.cn>
> ---
> Changes in v2:
> - Use auto cheanup to fix the problem.
> ---

Reviewed-by: Frank Li <Frank.Li at nxp.com>

>  drivers/interconnect/imx/imx.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/interconnect/imx/imx.c b/drivers/interconnect/imx/imx.c
> index 9511f80cf041..e5fcdcb88cfb 100644
> --- a/drivers/interconnect/imx/imx.c
> +++ b/drivers/interconnect/imx/imx.c
> @@ -120,7 +120,8 @@ static int imx_icc_node_init_qos(struct icc_provider *provider,
>  	struct imx_icc_node *node_data = node->data;
>  	const struct imx_icc_node_adj_desc *adj = node_data->desc->adj;
>  	struct device *dev = provider->dev;
> -	struct device_node *dn = NULL;
> +	struct device_node *__free(device_nod) dn = of_parse_phandle(dev->of_node,
> +			adj->phandle_name, 0);
>  	struct platform_device *pdev;
>
>  	if (adj->main_noc) {
> @@ -128,7 +129,6 @@ static int imx_icc_node_init_qos(struct icc_provider *provider,
>  		dev_dbg(dev, "icc node %s[%d] is main noc itself\n",
>  			node->name, node->id);
>  	} else {
> -		dn = of_parse_phandle(dev->of_node, adj->phandle_name, 0);
>  		if (!dn) {
>  			dev_warn(dev, "Failed to parse %s\n",
>  				 adj->phandle_name);
> @@ -138,12 +138,10 @@ static int imx_icc_node_init_qos(struct icc_provider *provider,
>  		if (!of_device_is_available(dn)) {
>  			dev_warn(dev, "Missing property %s, skip scaling %s\n",
>  				 adj->phandle_name, node->name);
> -			of_node_put(dn);
>  			return 0;
>  		}
>
>  		pdev = of_find_device_by_node(dn);
> -		of_node_put(dn);
>  		if (!pdev) {
>  			dev_warn(dev, "node %s[%d] missing device for %pOF\n",
>  				 node->name, node->id, dn);
> --
> 2.34.1
>