Re: [PATCH 1/7] mfd: 88pm860x: Fix possible NULL pointer dereference on i2c_new_dummy error

[Lee Jones <lee.jones@linaro.org>]

On Tue, 11 Feb 2014, Krzysztof Kozlowski wrote:

> During probe the driver allocates dummy I2C device for companion chip
> with i2c_new_dummy() but it does not check the return value of this call.
> 
> In case of error (i2c_new_device(): memory allocation failure or I2C
> address cannot be used) this function returns NULL which is later used
> by regmap_init_i2c().
> 
> If i2c_new_dummy() fails for companion device, fail also the probe for
> main MFD driver.
> 
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Cc: stable@vger.kernel.org
> ---
>  drivers/mfd/88pm860x-core.c |    5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/mfd/88pm860x-core.c b/drivers/mfd/88pm860x-core.c
> index c9b1f6422941..e456be9a7c67 100644
> --- a/drivers/mfd/88pm860x-core.c
> +++ b/drivers/mfd/88pm860x-core.c
> @@ -1179,6 +1179,11 @@ static int pm860x_probe(struct i2c_client *client,
>  		chip->companion_addr = pdata->companion_addr;
>  		chip->companion = i2c_new_dummy(chip->client->adapter,
>  						chip->companion_addr);
> +		if (!chip->companion) {
> +			dev_err(&client->dev,
> +				"Failed to allocate I2C companion device\n");
> +			return -ENODEV;
> +		}
>  		chip->regmap_companion = regmap_init_i2c(chip->companion,
>  							&pm860x_regmap_config);
>  		if (IS_ERR(chip->regmap_companion)) {

Applied, thanks.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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