Re: [PATCH net v2] net: rtsn: fix mdio_node leak in rtsn_mdio_alloc()

["Niklas Söderlund" <niklas.soderlund@ragnatech.se>]

Hi Shitalkumar,

Thanks for your work.

On 2026-05-05 18:02:36 +0530, Shitalkumar Gandhi wrote:
> of_get_child_by_name() takes a reference. The rtsn_reset() and
> rtsn_change_mode() failure paths jump to out_free_bus and leak
> mdio_node.
> 
> Add out_put_node to drop it before falling through.
> 
> Fixes: b0d3969d2b4d ("net: ethernet: rtsn: Add support for Renesas Ethernet-TSN")
> Signed-off-by: Shitalkumar Gandhi <shitalkumar.gandhi@cambiumnetworks.com>
> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

> ---
> Changes in v2:
> - Restore blank line between `return 0;` and `out_put_node:` label (Geert)
> - Add Reviewed-by: Geert Uytterhoeven
> 
> Resent as a new thread (no code changes) so netdev CI picks it up
> (Andrew).
> 
> Link to v1: https://lore.kernel.org/netdev/20260504200356.3529873-1-shitalkumar.gandhi@cambiumnetworks.com/
> Link to v2 (mis-threaded): https://lore.kernel.org/netdev/20260505085840.352206-1-shitalkumar.gandhi@cambiumnetworks.com/
> 
>  drivers/net/ethernet/renesas/rtsn.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/renesas/rtsn.c b/drivers/net/ethernet/renesas/rtsn.c
> index 03a2669f0518..ee8381b60b8d 100644
> --- a/drivers/net/ethernet/renesas/rtsn.c
> +++ b/drivers/net/ethernet/renesas/rtsn.c
> @@ -797,11 +797,11 @@ static int rtsn_mdio_alloc(struct rtsn_private *priv)
>  	/* Enter config mode before registering the MDIO bus */
>  	ret = rtsn_reset(priv);
>  	if (ret)
> -		goto out_free_bus;
> +		goto out_put_node;
>  
>  	ret = rtsn_change_mode(priv, OCR_OPC_CONFIG);
>  	if (ret)
> -		goto out_free_bus;
> +		goto out_put_node;
>  
>  	rtsn_modify(priv, MPIC, MPIC_PSMCS_MASK | MPIC_PSMHT_MASK,
>  		    MPIC_PSMCS_DEFAULT | MPIC_PSMHT_DEFAULT);
> @@ -824,6 +824,8 @@ static int rtsn_mdio_alloc(struct rtsn_private *priv)
>  
>  	return 0;
>  
> +out_put_node:
> +	of_node_put(mdio_node);
>  out_free_bus:
>  	mdiobus_free(mii);
>  	return ret;
> -- 
> 2.25.1
> 

-- 
Kind Regards,
Niklas Söderlund