Re: [PATCH] clk: samsung: exynos5433: Fix potential NULL pointer dereference

[Krzysztof Kozlowski <krzk@kernel.org>]

On Tue, Oct 01, 2019 at 03:09:21PM +0200, Marek Szyprowski wrote:
> devm_kcalloc might fail, so avoid accessing the allocated object in such
> case.
> 
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
>  drivers/clk/samsung/clk-exynos5433.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/samsung/clk-exynos5433.c b/drivers/clk/samsung/clk-exynos5433.c
> index 7824c2ba3d8e..6afbcd0ae96f 100644
> --- a/drivers/clk/samsung/clk-exynos5433.c
> +++ b/drivers/clk/samsung/clk-exynos5433.c
> @@ -5592,7 +5592,8 @@ static int __init exynos5433_cmu_probe(struct platform_device *pdev)
>  	if (data->nr_pclks > 0) {
>  		data->pclks = devm_kcalloc(dev, sizeof(struct clk *),
>  					   data->nr_pclks, GFP_KERNEL);
> -
> +		if (!data->pclks)
> +			return -ENOMEM;

You leak the memory from the samsung_clk_alloc_reg_dump() call.

The error path few lines later (from of_clk_get()) leaks it as well.

Best regards,
Krzysztof

>  		for (i = 0; i < data->nr_pclks; i++) {
>  			struct clk *clk = of_clk_get(dev->of_node, i);
>  
> -- 
> 2.17.1
>