Re: [PATCH] spi: wpcm-fiu: Fix potential NULL pointer dereference in wpcm_fiu_probe()

From: J. Neuschäfer

Date: Fri Feb 13 2026 - 06:06:27 EST


On Thu, Feb 12, 2026 at 08:41:40PM +0800, Felix Gu wrote:
> platform_get_resource_byname() can return NULL, which would cause a crash
> when passed the pointer to resource_size().
>
> Move the fiu->memory_size assignment after the error check for
> devm_ioremap_resource() to prevent the potential NULL pointer dereference.
>
> Fixes: 9838c182471e ("spi: wpcm-fiu: Add direct map support")
> Signed-off-by: Felix Gu <ustc.gu@xxxxxxxxx>
> ---

Seems reasonable.

Reviewed-by: J. Neuschäfer <j.ne@xxxxxxxxxx>

Thanks!

> drivers/spi/spi-wpcm-fiu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/spi/spi-wpcm-fiu.c b/drivers/spi/spi-wpcm-fiu.c
> index 0e3ee5516587..0e26ff178505 100644
> --- a/drivers/spi/spi-wpcm-fiu.c
> +++ b/drivers/spi/spi-wpcm-fiu.c
> @@ -459,11 +459,11 @@ static int wpcm_fiu_probe(struct platform_device *pdev)
>
> res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "memory");
> fiu->memory = devm_ioremap_resource(dev, res);
> - fiu->memory_size = min_t(size_t, resource_size(res), MAX_MEMORY_SIZE_TOTAL);
> if (IS_ERR(fiu->memory))
> return dev_err_probe(dev, PTR_ERR(fiu->memory),
> "Failed to map flash memory window\n");
>
> + fiu->memory_size = min_t(size_t, resource_size(res), MAX_MEMORY_SIZE_TOTAL);
> fiu->shm_regmap = syscon_regmap_lookup_by_phandle_optional(dev->of_node, "nuvoton,shm");
>
> wpcm_fiu_hw_init(fiu);
>
> ---
> base-commit: 9152bc8cebcb14dc16b03ec81f2377ee8ce12268
> change-id: 20260212-wpcm-d86f76761645
>
> Best regards,
> --
> Felix Gu <ustc.gu@xxxxxxxxx>
>