Re: [PATCH] mmc: dw_mmc: Fix to avoid potential NULL pointer dereferenceãèææïéäçlinux-mmc-owner@xxxxxxxxxxxxxxxäåã

[Shawn Lin]

On 2019/3/19 8:19, Aditya Pakki wrote:
> of_match_node can fail and return NULL in case no matching structure.
> The patches checks for such a scenario and returns -ENXIO.
>
> Signed-off-by: Aditya Pakki <pakki001@xxxxxxx>
> ---
>   drivers/mmc/host/dw_mmc-exynos.c | 2 ++
>   drivers/mmc/host/dw_mmc-k3.c     | 2 ++
>   drivers/mmc/host/dw_mmc-pltfm.c  | 2 ++
>   3 files changed, 6 insertions(+)

Could you check dw_mmc-zx.c and dw_mmc-rockchip.c as well?

> diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
> index d46c3439b508..8a75d7314606 100644
> --- a/drivers/mmc/host/dw_mmc-exynos.c
> +++ b/drivers/mmc/host/dw_mmc-exynos.c
> @@ -554,6 +554,8 @@ static int dw_mci_exynos_probe(struct platform_device *pdev)
>   	int ret;
>   
>   	match = of_match_node(dw_mci_exynos_match, pdev->dev.of_node);
> +	if (!match)
> +		return -ENXIO;
>   	drv_data = match->data;
>   
>   	pm_runtime_get_noresume(&pdev->dev);
> diff --git a/drivers/mmc/host/dw_mmc-k3.c b/drivers/mmc/host/dw_mmc-k3.c
> index 89cdb3d533bb..cc50b7546a20 100644
> --- a/drivers/mmc/host/dw_mmc-k3.c
> +++ b/drivers/mmc/host/dw_mmc-k3.c
> @@ -459,6 +459,8 @@ static int dw_mci_k3_probe(struct platform_device *pdev)
>   	const struct of_device_id *match;
>   
>   	match = of_match_node(dw_mci_k3_match, pdev->dev.of_node);
> +	if (!match)
> +		return -ENXIO;
>   	drv_data = match->data;
>   
>   	return dw_mci_pltfm_register(pdev, drv_data);
> diff --git a/drivers/mmc/host/dw_mmc-pltfm.c b/drivers/mmc/host/dw_mmc-pltfm.c
> index 58c13e21bd5a..b1948989f617 100644
> --- a/drivers/mmc/host/dw_mmc-pltfm.c
> +++ b/drivers/mmc/host/dw_mmc-pltfm.c
> @@ -82,6 +82,8 @@ static int dw_mci_pltfm_probe(struct platform_device *pdev)
>   
>   	if (pdev->dev.of_node) {
>   		match = of_match_node(dw_mci_pltfm_match, pdev->dev.of_node);
> +		if (!match)
> +			return -ENXIO;
>   		drv_data = match->data;
>   	}
>