Re: [PATCH] phy: core: fix potential UAF in of_phy_simple_xlate()

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Thu, Feb 19, 2026 at 03:57:11PM -0800, Dmitry Torokhov wrote:
> The implementation put_device()s located device and then uses
> container_of() on the pointer. The device may disappear by that time,
> resulting in UAF.
> 
> Fix the problem by keeping the reference to the framer device,
> avoiding getting an extra reference to it in framer_get(), and making
> sure to drop the reference in error path when we fail to get the module.

Hmm, I was too rash. There are bunch of other xlate functions that need
to be updated to take the reference.

> 
> Fixes: e6625db66212 ("phy: core: Simplify API of_phy_simple_xlate() implementation")
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---
>  drivers/phy/phy-core.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
> index 4ad396214d0c..cf62eb9ddca9 100644
> --- a/drivers/phy/phy-core.c
> +++ b/drivers/phy/phy-core.c
> @@ -682,10 +682,10 @@ struct phy *of_phy_get(struct device_node *np, const char *con_id)
>  	if (IS_ERR(phy))
>  		return phy;
>  
> -	if (!try_module_get(phy->ops->owner))
> +	if (!try_module_get(phy->ops->owner)) {
> +		put_device(&phy->dev);
>  		return ERR_PTR(-EPROBE_DEFER);
> -
> -	get_device(&phy->dev);
> +	}
>  
>  	return phy;
>  }
> @@ -765,7 +765,6 @@ struct phy *of_phy_simple_xlate(struct device *dev,
>  	if (!target_dev)
>  		return ERR_PTR(-ENODEV);
>  
> -	put_device(target_dev);
>  	return to_phy(target_dev);
>  }
>  EXPORT_SYMBOL_GPL(of_phy_simple_xlate);
> -- 
> 2.53.0.345.g96ddfc5eaa-goog
> 
> 

-- 
Dmitry