Re: [PATCH v7 8/8] iio: accel: mma8452: Use proper error code when missing device model

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Pre-existing memory leak of iio_trigger in mma8452_probe error paths.
--

commit 19ad2f8e418619267dc62918b9e4fe522127cae2
Author: Esben Haabendal <esben@geanix.com>

iio: accel: mma8452: Use proper error code when missing device model
    
Switch -ENODEV error on i2c_get_match_data() failure to -ENODATA to
satisfy the IIO coding style.

> diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
> index 9619b200fa5a9..9eaced6bf2429 100644
> --- a/drivers/iio/accel/mma8452.c
> +++ b/drivers/iio/accel/mma8452.c
> @@ -1597,7 +1597,7 @@ static int mma8452_probe(struct i2c_client *client)
>  
>  	data->chip_info = i2c_get_match_data(client);
>  	if (!data->chip_info)
> -		return dev_err_probe(dev, -ENODEV, "unknown device model\n");
> +		return dev_err_probe(dev, -ENODATA, "unknown device model\n");
>  
>  	ret = iio_read_mount_matrix(dev, &data->orientation);
>  	if (ret)

[Severity: High]
This isn't a bug introduced by this patch, but there is a pre-existing 
issue in the error handling of mma8452_probe further down in this function.

When mma8452_trigger_setup is called during probe, it elevates the trigger
reference count:

drivers/iio/accel/mma8452.c:mma8452_trigger_setup() {
    ...
    indio_dev->trig = iio_trigger_get(trig);
    ...
}

If a subsequent setup step fails, such as mma8452_set_interrupt_pin_mode,
the code jumps to the cleanup label:

drivers/iio/accel/mma8452.c:mma8452_probe() {
    ...
    ret = mma8452_set_interrupt_pin_mode(data);
    if (ret)
        goto trigger_cleanup;
    ...
}

The error path leaps directly to the final mma8452_trigger_cleanup. Because 
the triggered buffer mode flag is not yet set at the time of failure, the 
IIO core omits bridging cleanup logic and skips the iio_trigger_put call.

Does this result in permanently leaking the trigger device memory?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260831-mma8452-open-drain-v7-0-22946812c928@geanix.com?part=8