Re: [PATCH] clk: imx: clk-imx8mm: fix memory leak issue in 'imx8mm_clocks_probe'

[周师德]

> -----原始邮件-----
> 发件人: "Zhou Shide" <u201911681@xxxxxxxxxxx>
> 发送时间: 2023-04-13 11:24:39 (星期四)
> 收件人: "Abel Vesa" <abelvesa@xxxxxxxxxx>, "Peng Fan" <peng.fan@xxxxxxx>, "Michael Turquette" <mturquette@xxxxxxxxxxxx>, "Stephen Boyd" <sboyd@xxxxxxxxxx>, "Shawn Guo" <shawnguo@xxxxxxxxxx>, "Sascha Hauer" <s.hauer@xxxxxxxxxxxxxx>, "Pengutronix Kernel Team" <kernel@xxxxxxxxxxxxxx>, "Fabio Estevam" <festevam@xxxxxxxxx>, "NXP Linux Team" <linux-imx@xxxxxxx>, "Bai Ping" <ping.bai@xxxxxxx>
> 抄送: hust-os-kernel-patches@xxxxxxxxxxxxxxxx, "Zhou Shide" <u201911681@xxxxxxxxxxx>, linux-clk@xxxxxxxxxxxxxxx, linux-arm-kernel@xxxxxxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx
> 主题: [PATCH] clk: imx: clk-imx8mm: fix memory leak issue in 'imx8mm_clocks_probe'
> 
> The function imx8mm_clocks_probe() has two main issues:
> - The of_iomap() function may cause a memory leak.
> - Memory allocated for 'clk_hw_data' may not be freed properly
> in some paths.
> 
> To fix these issues, this commit replaces the use of of_iomap()
> with devm_of_iomap() and replaces kzalloc() with devm_kzalloc().
> This ensures that all memory is properly managed and automatically
> freed when the device is removed.
> 
> In addition, when devm_of_iomap() allocates memory with an error,
> it will first jump to label "unregister_hws" and
> then return PTR_ ERR(base).
> 
> Fixes: 9c71f9ea35d7 ("clk: imx: imx8mm: Switch to clk_hw based API")
> Fixes: ba5625c3e272 ("clk: imx: Add clock driver support for imx8mm")
> Signed-off-by: Zhou Shide <u201911681@xxxxxxxxxxx>
> ---
> The issue is discovered by static analysis, and the patch is not tested yet.
> 
>  drivers/clk/imx/clk-imx8mm.c | 16 ++++++++++------
>  1 file changed, 10 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/clk/imx/clk-imx8mm.c b/drivers/clk/imx/clk-imx8mm.c
> index b618892170f2..e6e0bb4805a6 100644
> --- a/drivers/clk/imx/clk-imx8mm.c
> +++ b/drivers/clk/imx/clk-imx8mm.c
> @@ -303,7 +303,7 @@ static int imx8mm_clocks_probe(struct platform_device *pdev)
>  	void __iomem *base;
>  	int ret;
>  
> -	clk_hw_data = kzalloc(struct_size(clk_hw_data, hws,
> +	clk_hw_data = devm_kzalloc(dev, struct_size(clk_hw_data, hws,
>  					  IMX8MM_CLK_END), GFP_KERNEL);
>  	if (WARN_ON(!clk_hw_data))
>  		return -ENOMEM;
> @@ -320,10 +320,12 @@ static int imx8mm_clocks_probe(struct platform_device *pdev)
>  	hws[IMX8MM_CLK_EXT4] = imx_get_clk_hw_by_name(np, "clk_ext4");
>  
>  	np = of_find_compatible_node(NULL, NULL, "fsl,imx8mm-anatop");
> -	base = of_iomap(np, 0);
> +	base = devm_of_iomap(dev, np, 0, NULL);
>  	of_node_put(np);
> -	if (WARN_ON(!base))
> -		return -ENOMEM;
> +	if (WARN_ON(IS_ERR(base))) {
> +		ret = PTR_ERR(base);
> +		goto unregister_hws;
> +	}
>  
>  	hws[IMX8MM_AUDIO_PLL1_REF_SEL] = imx_clk_hw_mux("audio_pll1_ref_sel", base + 0x0, 0, 2, pll_ref_sels, ARRAY_SIZE(pll_ref_sels));
>  	hws[IMX8MM_AUDIO_PLL2_REF_SEL] = imx_clk_hw_mux("audio_pll2_ref_sel", base + 0x14, 0, 2, pll_ref_sels, ARRAY_SIZE(pll_ref_sels));
> @@ -399,8 +401,10 @@ static int imx8mm_clocks_probe(struct platform_device *pdev)
>  
>  	np = dev->of_node;
>  	base = devm_platform_ioremap_resource(pdev, 0);
> -	if (WARN_ON(IS_ERR(base)))
> -		return PTR_ERR(base);
> +	if (WARN_ON(IS_ERR(base))) {
> +		ret = PTR_ERR(base);
> +		goto unregister_hws;
> +	}
>  
>  	/* Core Slice */
>  	hws[IMX8MM_CLK_A53_DIV] = imx8m_clk_hw_composite_core("arm_a53_div", imx8mm_a53_sels, base + 0x8000);
> -- 
> 2.34.1
ping？