Re: [PATCH] clk: imx: clk-imxrt1050: fix memory leak in imxrt1050_clocks_probe

[Jesse Taube]

On 4/18/23 07:34, Kai Ma wrote:
> Use devm_of_iomap() instead of of_iomap() to automatically
> handle the unused ioremap region. If any error occurs, regions allocated by
> kzalloc() will leak, but using devm_kzalloc() instead will automatically
> free the memory using devm_kfree().
> 
> Also, fix error handling of hws by adding unregister_hws label, which
> unregisters remaining hws when iomap failed.
> 
> Fixes: 7154b046d8f3 ("clk: imx: Add initial support for i.MXRT1050 clock driver")
> Signed-off-by: Kai Ma <kaima@xxxxxxxxxxx>
> ---
> The issue is found by static analysis and remains untested.
> ---
>  drivers/clk/imx/clk-imxrt1050.c | 22 +++++++++++++++-------
>  1 file changed, 15 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/clk/imx/clk-imxrt1050.c b/drivers/clk/imx/clk-imxrt1050.c
> index fd5c51fc92c0..08d155feb035 100644
> --- a/drivers/clk/imx/clk-imxrt1050.c
> +++ b/drivers/clk/imx/clk-imxrt1050.c
> @@ -42,7 +42,7 @@ static int imxrt1050_clocks_probe(struct platform_device *pdev)
>  	struct device_node *anp;
>  	int ret;
>  
> -	clk_hw_data = kzalloc(struct_size(clk_hw_data, hws,
> +	clk_hw_data = devm_kzalloc(dev, struct_size(clk_hw_data, hws,
>  					  IMXRT1050_CLK_END), GFP_KERNEL);
>  	if (WARN_ON(!clk_hw_data))
>  		return -ENOMEM;
> @@ -53,10 +53,12 @@ static int imxrt1050_clocks_probe(struct platform_device *pdev)
>  	hws[IMXRT1050_CLK_OSC] = imx_get_clk_hw_by_name(np, "osc");
>  
>  	anp = of_find_compatible_node(NULL, NULL, "fsl,imxrt-anatop");
> -	pll_base = of_iomap(anp, 0);
> +	pll_base = devm_of_iomap(dev, anp, 0, NULL);
>  	of_node_put(anp);
> -	if (WARN_ON(!pll_base))
> -		return -ENOMEM;
> +	if (WARN_ON(IS_ERR(pll_base))) {
> +		ret = PTR_ERR(pll_base);
> +		goto unregister_hws;
> +	}
>  
>  	/* Anatop clocks */
>  	hws[IMXRT1050_CLK_DUMMY] = imx_clk_hw_fixed("dummy", 0UL);
> @@ -104,8 +106,10 @@ static int imxrt1050_clocks_probe(struct platform_device *pdev)
>  
>  	/* CCM clocks */
>  	ccm_base = devm_platform_ioremap_resource(pdev, 0);
> -	if (WARN_ON(IS_ERR(ccm_base)))
> -		return PTR_ERR(ccm_base);
> +	if (WARN_ON(IS_ERR(ccm_base))) {
> +		ret = PTR_ERR(ccm_base);
> +		goto unregister_hws;
> +	}
>  
>  	hws[IMXRT1050_CLK_ARM_PODF] = imx_clk_hw_divider("arm_podf", "pll1_arm", ccm_base + 0x10, 0, 3);
>  	hws[IMXRT1050_CLK_PRE_PERIPH_SEL] = imx_clk_hw_mux("pre_periph_sel", ccm_base + 0x18, 18, 2,
> @@ -149,8 +153,12 @@ static int imxrt1050_clocks_probe(struct platform_device *pdev)
>  	ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, clk_hw_data);
>  	if (ret < 0) {
>  		dev_err(dev, "Failed to register clks for i.MXRT1050.\n");
> -		imx_unregister_hw_clocks(hws, IMXRT1050_CLK_END);
> +		goto unregister_hws;
>  	}
> +	return 0;
> +
> +unregister_hws:
> +	imx_unregister_hw_clocks(hws, IMXRT1050_CLK_END);
>  	return ret;
>  }
>  static const struct of_device_id imxrt1050_clk_of_match[] = {
Looks good! The fix seems to be similar to how clk-imx8mn.c does this.

Acked-by: Jesse Taube <Mr.Bossman075@xxxxxxxxx>

A similar issue seems to also be in drivers/clk/imx/clk-imx8mm.c,clk-imx93.c,clk-imx8mp.c.
Sorry for recreating the issue :(.

Thanks,
Jesse Taube