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Message-ID: <768ae986-a67b-fedc-d43b-94096d1dd6bb@linaro.org>
Date:   Mon, 31 Jul 2023 10:53:02 +0200
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From:   neil.armstrong@linaro.org
Reply-To: neil.armstrong@linaro.org
Subject: Re: [PATCH] firmware: meson_sm: fix to avoid potential NULL pointer
 dereference
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To:     Zhang Shurong <zhang_shurong@foxmail.com>
Cc:     khilman@baylibre.com, jbrunet@baylibre.com,
        martin.blumenstingl@googlemail.com,
        linux-arm-kernel@lists.infradead.org,
        linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org
References: <tencent_AA08AAA6C4F34D53ADCE962E188A879B8206@qq.com>
Organization: Linaro Developer Services
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On 15/07/2023 16:13, Zhang Shurong wrote:
> of_match_device() may fail and returns a NULL pointer.
> 
> Fix this by checking the return value of of_match_device.
> 
> Fixes: 8cde3c2153e8 ("firmware: meson_sm: Rework driver as a proper platform driver")
> Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
> ---
>   drivers/firmware/meson/meson_sm.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/firmware/meson/meson_sm.c b/drivers/firmware/meson/meson_sm.c
> index 798bcdb05d84..9a2656d73600 100644
> --- a/drivers/firmware/meson/meson_sm.c
> +++ b/drivers/firmware/meson/meson_sm.c
> @@ -292,6 +292,8 @@ static int __init meson_sm_probe(struct platform_device *pdev)
>   		return -ENOMEM;
>   
>   	chip = of_match_device(meson_sm_ids, dev)->data;
> +	if (!chip)
> +		return -EINVAL;
>   
>   	if (chip->cmd_shmem_in_base) {
>   		fw->sm_shmem_in_base = meson_sm_map_shmem(chip->cmd_shmem_in_base,


Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>