Re: [PATCH v2] mmc: sh_mmcif: Check for null res pointer

From: Ulf Hansson
Date: Fri Jan 21 2022 - 09:32:49 EST


On Wed, 19 Jan 2022 at 13:00, Jiasheng Jiang <jiasheng@xxxxxxxxxxx> wrote:
>
> If there is no suitable resource, platform_get_resource() will return
> NULL.
> Therefore in order to avoid the dereference of the NULL pointer, it
> should be better to check the 'res'.
>
> Fixes: df0cc57e057f ("Linux 5.16")

I have changed this to:
Cc: stable@xxxxxxxxxxxxxxx # v5.16+

> Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>

Applied for fixes, thanks!

Kind regards
Uffe


> ---
> Changelog
>
> v1 -> v2
>
> * Change 1. Change the fixes tag to v5.16.
> ---
> drivers/mmc/host/sh_mmcif.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
> index e5e457037235..45dfa3b0be9c 100644
> --- a/drivers/mmc/host/sh_mmcif.c
> +++ b/drivers/mmc/host/sh_mmcif.c
> @@ -405,6 +405,9 @@ static int sh_mmcif_dma_slave_config(struct sh_mmcif_host *host,
> struct dma_slave_config cfg = { 0, };
>
> res = platform_get_resource(host->pd, IORESOURCE_MEM, 0);
> + if (!res)
> + return -EINVAL;
> +
> cfg.direction = direction;
>
> if (direction == DMA_DEV_TO_MEM) {
> --
> 2.25.1
>