From: Jiasheng Jiang <jiasheng@xxxxxxxxxxx> commit 4d315357b3d6c315a7260420c6c6fc076e58d14b upstream. 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'. Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx # v5.16+ Link: https://lore.kernel.org/r/20220119120006.1426964-1-jiasheng@xxxxxxxxxxx Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/mmc/host/sh_mmcif.c | 3 +++ 1 file changed, 3 insertions(+) --- 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(str 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) {
