Subject: Re: [PATCH] mmc: dw_mmc: Fix potential null pointer risk
To:     Wen Zhiwei <wenzhiwei@kylinos.cn>, ulf.hansson@linaro.org,
        p.zabel@pengutronix.de
Cc:     linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org
From:   Jaehoon Chung <jh80.chung@samsung.com>
Message-ID: <beeb83e9-415c-cf36-9cec-f9bc277442ed@samsung.com>
Date:   Thu, 30 Dec 2021 17:35:32 +0900
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        <20211229023814.53372-1-wenzhiwei@kylinos.cn>
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On 12/29/21 11:38 AM, Wen Zhiwei wrote:
> we previously assumed 'host->slot' could be null,
> null pointer judgment should be added
> 
> Signed-off-by: Wen Zhiwei <wenzhiwei@kylinos.cn>

Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>

Beset Regards,
Jaehoon Chung

> ---
>  drivers/mmc/host/dw_mmc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index d977f34f6b55..c9dc8c168efb 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -3518,7 +3518,7 @@ int dw_mci_runtime_resume(struct device *dev)
>  	mci_writel(host, CTRL, SDMMC_CTRL_INT_ENABLE);
>  
>  
> -	if (host->slot->mmc->pm_flags & MMC_PM_KEEP_POWER)
> +	if (host->slot && host->slot->mmc->pm_flags & MMC_PM_KEEP_POWER)
>  		dw_mci_set_ios(host->slot->mmc, &host->slot->mmc->ios);
>  
>  	/* Force setup bus to guarantee available clock output */
>