Re: [PATCH] Mfd - Fix possible NULL derefrence.

From: Andy Shevchenko
Date: Tue Feb 07 2017 - 06:51:39 EST


On Fri, Jan 27, 2017 at 1:16 PM, Shailendra Verma
<shailendra.v@xxxxxxxxxxx> wrote:
> of_match_device could return NULL, and so can cause a NULL
> pointer dereference later.

I think it's not possible.

> --- a/drivers/mfd/mc13xxx-i2c.c
> +++ b/drivers/mfd/mc13xxx-i2c.c
> @@ -80,6 +80,10 @@ static int mc13xxx_i2c_probe(struct i2c_client *client,
> if (client->dev.of_node) {
> const struct of_device_id *of_id =
> of_match_device(mc13xxx_dt_ids, &client->dev);
> + if (!of_id) {
> + dev_err(&client->dev, "Error: No device match found\n");
> + return -ENODEV;
> + }
> mc13xxx->variant = of_id->data;
> } else {
> mc13xxx->variant = (void *)id->driver_data;
> diff --git a/drivers/mfd/mc13xxx-spi.c b/drivers/mfd/mc13xxx-spi.c
> index cbc1e5e..97ab19c 100644
> --- a/drivers/mfd/mc13xxx-spi.c
> +++ b/drivers/mfd/mc13xxx-spi.c
> @@ -157,7 +157,10 @@ static int mc13xxx_spi_probe(struct spi_device *spi)
> if (spi->dev.of_node) {
> const struct of_device_id *of_id =
> of_match_device(mc13xxx_dt_ids, &spi->dev);
> + if (!of_id) {
> + dev_err(&spi->dev, "Error: No device match found\n");
> + return -ENODEV;
> + }
> mc13xxx->variant = of_id->data;
> } else {
> const struct spi_device_id *id_entry = spi_get_device_id(spi);
> --
> 1.7.9.5
>



--
With Best Regards,
Andy Shevchenko