RE: [PATCH] net: ethernet: renesas: rswitch: fix device_node refcount leak in rswitch_get_port_node()

Hello Manush,

Thank you for your patch.

> -----Original Message-----
> From: Manush Prajwal <[email protected]>
> Sent: Thursday, August 13, 2026 1:11 PM
> To: Yoshihiro Shimoda <[email protected]>
> Cc: [email protected]; [email protected]; Manush Prajwal
> <[email protected]>
> Subject: [PATCH] net: ethernet: renesas: rswitch: fix device_node refcount leak in
> rswitch_get_port_node()
> 
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> 
> On an of_property_read_u32() failure, rswitch_get_port_node() sets port to NULL and jumps to the out
> label before releasing the reference the for_each_available_child_of_node() iterator was holding on
> it. Once port is overwritten with NULL, that reference can never be released since out: only puts
> "ports", the parent node. Call
> of_node_put(port) before clearing it.
> 
> Signed-off-by: Manush Prajwal <[email protected]>
> ---
>  drivers/net/ethernet/renesas/rswitch_main.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/ethernet/renesas/rswitch_main.c b/drivers/net/ethernet/renesas/rswitch_main.c
> index 6fe9648163..ffdc42f430 100644
> --- a/drivers/net/ethernet/renesas/rswitch_main.c
> +++ b/drivers/net/ethernet/renesas/rswitch_main.c
> @@ -1315,6 +1315,7 @@ static struct device_node *rswitch_get_port_node(struct rswitch_device *rdev)
>         for_each_available_child_of_node(ports, port) {
>                 err = of_property_read_u32(port, "reg", &index);
>                 if (err < 0) {
> +                       of_node_put(port);

I am not sure why you are adding this here. The code jumps to the label "out" and that is where 
"of_node_put(port)" is called. Is there a reason why you want to call this twice in a row?

Best regards,

Michael


>                         port = NULL;
>                         goto out;
>                 }
> --
> 2.46.2.windows.1
>