Re: [PATCH v12 2/3] hwmon: ltc4283: Add support for the LTC4283 Swap Controller

On Thu, Apr 30, 2026 at 07:52:55AM -0700, Guenter Roeck wrote:
> On 4/30/26 03:03, [email protected] wrote:
> ...
> > > +	id = (client->adapter->nr << 10) | client->addr;
> > > +	adev = __devm_auxiliary_device_create(dev, KBUILD_MODNAME, "gpio",
> > > +					      &st->gpio_mask, id);
> > > +	if (!adev)
> > > +		return dev_err_probe(dev, -ENODEV, "Failed to add GPIO device\n");
> > 
> > Can this error path lead to a use-after-free?
> > 
> > According to the I2C subsystem rules, debugfs entries attached to the
> > client debugfs directory are only cleaned up during the client device
> > removal function on driver unbind.
> > 
> > If __devm_auxiliary_device_create() fails, the probe function aborts and
> > the devres subsystem frees the st pointer. However, the debugfs files
> > persist and retain operations that operate on the freed st pointer.
> > 
> 
> AI taking everything literally :-(. I'll have to reword that guidance again
> to include the probe error path.
> 

Yeah and it is annoying it always comes up with something that could
have been said before. Even more annoying some of are legit issues :)

- Nuno Sá

> Guenter
>