Re: [PATCH] memory: fsl_ifc: fix leak of irq and nand_irq in fsl_ifc_ctrl_probe

[Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>]

On 03/08/2021 09:51, Dongliang Mu wrote:
> In fsl_ifc_ctrl_probe, if fsl_ifc_ctrl_init fails, we should free the
> resources allocated by irq_of_parse_and_map.

Your code is doing much more. You also touch nand_irq, not only
fsl_ifc_ctrl_init(). This looks incorrect as IRQ is optional, isn't it?

The problem is entirely different than you described here - the error
paths of fsl_ifc_ctrl_init() and request_irq() are wrong. They do not
release resources in proper paths.



Best regards,
Krzysztof

> 
> Fix this by adjusting the error handling code.
> 
> Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
> ---
>  drivers/memory/fsl_ifc.c | 19 ++++++++++++-------
>  1 file changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/memory/fsl_ifc.c b/drivers/memory/fsl_ifc.c
> index d062c2f8250f..391390dd3dcb 100644
> --- a/drivers/memory/fsl_ifc.c
> +++ b/drivers/memory/fsl_ifc.c
> @@ -258,12 +258,17 @@ static int fsl_ifc_ctrl_probe(struct platform_device *dev)
>  	/* get the nand machine irq */
>  	fsl_ifc_ctrl_dev->nand_irq =
>  			irq_of_parse_and_map(dev->dev.of_node, 1);
> +	if (fsl_ifc_ctrl_dev->nand_irq == 0) {
> +		dev_err(&dev->dev, "failed to get nand_irq resource for IFC\n");
> +		ret = -ENODEV;
> +		goto err_unmap_irq;
> +	}
>  
>  	fsl_ifc_ctrl_dev->dev = &dev->dev;
>  
>  	ret = fsl_ifc_ctrl_init(fsl_ifc_ctrl_dev);
>  	if (ret < 0)
> -		goto err;
> +		goto err_unmap_nandirq;
>  
>  	init_waitqueue_head(&fsl_ifc_ctrl_dev->nand_wait);
>  
> @@ -272,7 +277,7 @@ static int fsl_ifc_ctrl_probe(struct platform_device *dev)
>  	if (ret != 0) {
>  		dev_err(&dev->dev, "failed to install irq (%d)\n",
>  			fsl_ifc_ctrl_dev->irq);
> -		goto err_irq;
> +		goto err_unmap_nandirq;
>  	}
>  
>  	if (fsl_ifc_ctrl_dev->nand_irq) {
> @@ -281,17 +286,17 @@ static int fsl_ifc_ctrl_probe(struct platform_device *dev)
>  		if (ret != 0) {
>  			dev_err(&dev->dev, "failed to install irq (%d)\n",
>  				fsl_ifc_ctrl_dev->nand_irq);
> -			goto err_nandirq;
> +			goto err_free_irq;
>  		}
>  	}
>  
>  	return 0;
>  
> -err_nandirq:
> -	free_irq(fsl_ifc_ctrl_dev->nand_irq, fsl_ifc_ctrl_dev);
> -	irq_dispose_mapping(fsl_ifc_ctrl_dev->nand_irq);
> -err_irq:
> +err_free_irq:
>  	free_irq(fsl_ifc_ctrl_dev->irq, fsl_ifc_ctrl_dev);
> +err_unmap_nandirq:
> +	irq_dispose_mapping(fsl_ifc_ctrl_dev->nand_irq);
> +err_unmap_irq:
>  	irq_dispose_mapping(fsl_ifc_ctrl_dev->irq);
>  err:
>  	iounmap(fsl_ifc_ctrl_dev->gregs);
>