Re: [PATCH] spi: spi-fsl-lpspi: remove redundant spi_controller_put call

From: Sverdlin, Alexander
Date: Wed Apr 03 2024 - 04:51:49 EST


Hi Carlos!

On Wed, 2024-04-03 at 16:40 +0800, carlos.song@xxxxxxx wrote:
> devm_spi_alloc_controller will allocate an SPI controller and
> automatically release a reference on it when dev is unbound from
> its driver. It doesn't need to call spi_controller_put explicitly
> to put the reference when lpspi driver failed initialization.
>
> Fixes: 2ae0ab0143fc ("spi: lpspi: Avoid potential use-after-free in probe()")
> Signed-off-by: Carlos Song <carlos.song@xxxxxxx>

You are absolutely right!
Sorry for the stupid mistake and thanks for the patch!

Reviewed-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>

> ---
>  drivers/spi/spi-fsl-lpspi.c | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
> index 079035db7dd8..92a662d1b55c 100644
> --- a/drivers/spi/spi-fsl-lpspi.c
> +++ b/drivers/spi/spi-fsl-lpspi.c
> @@ -852,39 +852,39 @@ static int fsl_lpspi_probe(struct platform_device *pdev)
>         fsl_lpspi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
>         if (IS_ERR(fsl_lpspi->base)) {
>                 ret = PTR_ERR(fsl_lpspi->base);
> -               goto out_controller_put;
> +               return ret;
>         }
>         fsl_lpspi->base_phys = res->start;
>  
>         irq = platform_get_irq(pdev, 0);
>         if (irq < 0) {
>                 ret = irq;
> -               goto out_controller_put;
> +               return ret;
>         }
>  
>         ret = devm_request_irq(&pdev->dev, irq, fsl_lpspi_isr, 0,
>                                dev_name(&pdev->dev), fsl_lpspi);
>         if (ret) {
>                 dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
> -               goto out_controller_put;
> +               return ret;
>         }
>  
>         fsl_lpspi->clk_per = devm_clk_get(&pdev->dev, "per");
>         if (IS_ERR(fsl_lpspi->clk_per)) {
>                 ret = PTR_ERR(fsl_lpspi->clk_per);
> -               goto out_controller_put;
> +               return ret;
>         }
>  
>         fsl_lpspi->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
>         if (IS_ERR(fsl_lpspi->clk_ipg)) {
>                 ret = PTR_ERR(fsl_lpspi->clk_ipg);
> -               goto out_controller_put;
> +               return ret;
>         }
>  
>         /* enable the clock */
>         ret = fsl_lpspi_init_rpm(fsl_lpspi);
>         if (ret)
> -               goto out_controller_put;
> +               return ret;
>  
>         ret = pm_runtime_get_sync(fsl_lpspi->dev);
>         if (ret < 0) {
> @@ -945,8 +945,6 @@ static int fsl_lpspi_probe(struct platform_device *pdev)
>         pm_runtime_dont_use_autosuspend(fsl_lpspi->dev);
>         pm_runtime_put_sync(fsl_lpspi->dev);
>         pm_runtime_disable(fsl_lpspi->dev);
> -out_controller_put:
> -       spi_controller_put(controller);
>  
>         return ret;
>  }

--
Alexander Sverdlin
Siemens AG
www.siemens.com