Re: [PATCH] (powerpc/512) Fix possible `dma_unmap_single()` on uninitialized pointer

[Christophe Leroy]

Le 05/06/2025 à 18:37, Thomas Fourier a écrit :
> [Vous ne recevez pas souvent de courriers de fourier.thomas@xxxxxxxxx. Découvrez pourquoi ceci est important à https://aka.ms/LearnAboutSenderIdentification ]
>
> If the device configuration fails (if `dma_dev->device_config()`),
> `sg_dma_address(&sg)` is not initialized and the jump to `err_dma_prep`
> leads to calling `dma_unmap_single()` on `sg_dma_address(&sg)`.
>
> Signed-off-by: Thomas Fourier <fourier.thomas@xxxxxxxxx>
> ---
>   arch/powerpc/platforms/512x/mpc512x_lpbfifo.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
> index 9668b052cd4b..ef3be438f914 100644
> --- a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
> +++ b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
> @@ -241,8 +241,7 @@ static int mpc512x_lpbfifo_kick(void)
>
>          /* Make DMA channel work with LPB FIFO data register */
>          if (dma_dev->device_config(lpbfifo.chan, &dma_conf)) {
> -               ret = -EINVAL;
> -               goto err_dma_prep;
> +               return -EINVAL;
>          }

You should remove the { } as it is now a single line.

>          sg_init_table(&sg, 1);
> --
> 2.43.0