Re: [PATCH] libnvdimm/of_pmem: Add check and kfree for kstrdup

[Ira Weiny]

Jiasheng Jiang wrote:
> Add check for the return value of kstrdup() and return the error
> if it fails in order to avoid NULL pointer dereference.
> Moreover, use kfree() in the later error handling in order to avoid
> memory leak.
> 
> Fixes: 49bddc73d15c ("libnvdimm/of_pmem: Provide a unique name for bus provider")
> Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
> ---
>  drivers/nvdimm/of_pmem.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/nvdimm/of_pmem.c b/drivers/nvdimm/of_pmem.c
> index 10dbdcdfb9ce..fe6edb7e6631 100644
> --- a/drivers/nvdimm/of_pmem.c
> +++ b/drivers/nvdimm/of_pmem.c
> @@ -31,11 +31,17 @@ static int of_pmem_region_probe(struct platform_device *pdev)
>  		return -ENOMEM;
>  
>  	priv->bus_desc.provider_name = kstrdup(pdev->name, GFP_KERNEL);
> +	if (!priv->bus_desc.provider_name) {
> +		kfree(priv);
> +		return -ENOMEM;
> +	}
> +
>  	priv->bus_desc.module = THIS_MODULE;
>  	priv->bus_desc.of_node = np;
>  
>  	priv->bus = bus = nvdimm_bus_register(&pdev->dev, &priv->bus_desc);
>  	if (!bus) {
> +		kfree(priv->bus_desc.provider_name);

Nice catch!

However, this free needs to happen in of_pmem_region_remove() as well.

Ira

>  		kfree(priv);
>  		return -ENODEV;
>  	}
> -- 
> 2.25.1
>