Re: [PATCH] spi: ep93xx: fix error pointer deref after DMA setup failure

[Nikita Shubin]

On Tue, 2026-05-12 at 09:48 +0200, Johan Hovold wrote:
> The driver falls back to PIO mode if DMA setup fails during probe.
> 
> Make sure to the clear the DMA channel pointers on setup failure to
> avoid dereferencing an error pointer on later probe errors or driver
> unbind.
> 
> This issue was flagged by Sashiko when reviewing a devres allocation
> conversion patch.
> 
> Fixes: e79e7c2df627 ("spi: ep93xx: add DT support for Cirrus EP93xx")
> Link:
> https://sashiko.dev/#/patchset/20260429091333.165363-1-johan%40kernel.org?part=10
> Cc: stable@xxxxxxxxxxxxxxx	# 6.12
> Cc: Nikita Shubin <nikita.shubin@xxxxxxxxxxx>
> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>

Acked-by: Nikita Shubin <nikita.shubin@xxxxxxxxxxx>

> ---
>  drivers/spi/spi-ep93xx.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/spi/spi-ep93xx.c b/drivers/spi/spi-ep93xx.c
> index db50018050e5..f716c9607be4 100644
> --- a/drivers/spi/spi-ep93xx.c
> +++ b/drivers/spi/spi-ep93xx.c
> @@ -582,12 +582,14 @@ static int ep93xx_spi_setup_dma(struct device
> *dev, struct ep93xx_spi *espi)
>  	espi->dma_rx = dma_request_chan(dev, "rx");
>  	if (IS_ERR(espi->dma_rx)) {
>  		ret = dev_err_probe(dev, PTR_ERR(espi->dma_rx), "rx
> DMA setup failed");
> +		espi->dma_rx = NULL;
>  		goto fail_free_page;
>  	}
>  
>  	espi->dma_tx = dma_request_chan(dev, "tx");
>  	if (IS_ERR(espi->dma_tx)) {
>  		ret = dev_err_probe(dev, PTR_ERR(espi->dma_tx), "tx
> DMA setup failed");
> +		espi->dma_tx = NULL;
>  		goto fail_release_rx;
>  	}
>