Re: [PATCH v2 1/2] mfd: intel_quark_i2c_gpio: remove clock tree on error path

[Lee Jones]

On Fri, 19 Feb 2016, Andy Shevchenko wrote:

> There is a potential resource leak in case when ->probe() fails. We have to
> unregister and remove clock tree which is done here.
> 
> This is a follow up to previously pushed commit c4726abce63b ("mfd:
> intel_quark_i2c_gpio: Use clkdev_create()") that prevents double free() when
> clkdev_drop() followed by kfree() in devm_kcalloc() release stage.
> 
> I leave Fixes tag here, but the backporting will require to backport the commit
> c4726abce63b ("mfd: intel_quark_i2c_gpio: Use clkdev_create()") first.
> 
> Fixes: 60ae5b9f5cdd (mfd: intel_quark_i2c_gpio: Add Intel Quark X1000 I2C-GPIO MFD Driver)
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
> v2:
> - do not unregister clock before lookup (Stephen)
>  drivers/mfd/intel_quark_i2c_gpio.c | 25 +++++++++++++++++--------
>  1 file changed, 17 insertions(+), 8 deletions(-)

Applied, thanks.

> diff --git a/drivers/mfd/intel_quark_i2c_gpio.c b/drivers/mfd/intel_quark_i2c_gpio.c
> index bdc5e27..7450f5d 100644
> --- a/drivers/mfd/intel_quark_i2c_gpio.c
> +++ b/drivers/mfd/intel_quark_i2c_gpio.c
> @@ -139,6 +139,7 @@ static int intel_quark_register_i2c_clk(struct intel_quark_mfd *quark_mfd)
>  						INTEL_QUARK_I2C_CONTROLLER_CLK);
>  
>  	if (!quark_mfd->i2c_clk_lookup) {
> +		clk_unregister(quark_mfd->i2c_clk);
>  		dev_err(&pdev->dev, "Fixed clk register failed\n");
>  		return -ENOMEM;
>  	}
> @@ -150,7 +151,7 @@ static void intel_quark_unregister_i2c_clk(struct pci_dev *pdev)
>  {
>  	struct intel_quark_mfd *quark_mfd = dev_get_drvdata(&pdev->dev);
>  
> -	if (!quark_mfd->i2c_clk || !quark_mfd->i2c_clk_lookup)
> +	if (!quark_mfd->i2c_clk_lookup)
>  		return;
>  
>  	clkdev_drop(quark_mfd->i2c_clk_lookup);
> @@ -246,25 +247,33 @@ static int intel_quark_mfd_probe(struct pci_dev *pdev,
>  	quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
>  	if (!quark_mfd)
>  		return -ENOMEM;
> +
>  	quark_mfd->pdev = pdev;
> +	dev_set_drvdata(&pdev->dev, quark_mfd);
>  
>  	ret = intel_quark_register_i2c_clk(quark_mfd);
>  	if (ret)
>  		return ret;
>  
> -	dev_set_drvdata(&pdev->dev, quark_mfd);
> -
>  	ret = intel_quark_i2c_setup(pdev, &intel_quark_mfd_cells[1]);
>  	if (ret)
> -		return ret;
> +		goto err_unregister_i2c_clk;
>  
>  	ret = intel_quark_gpio_setup(pdev, &intel_quark_mfd_cells[0]);
>  	if (ret)
> -		return ret;
> +		goto err_unregister_i2c_clk;
>  
> -	return mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
> -			       ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
> -			       NULL);
> +	ret = mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
> +			      ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
> +			      NULL);
> +	if (ret)
> +		goto err_unregister_i2c_clk;
> +
> +	return 0;
> +
> +err_unregister_i2c_clk:
> +	intel_quark_unregister_i2c_clk(pdev);
> +	return ret;
>  }
>  
>  static void intel_quark_mfd_remove(struct pci_dev *pdev)

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