Re: [PATCH v2] (powerpc/512) Fix possible `dma_unmap_single()` on uninitialized pointer

[Christophe Leroy]

Le 10/06/2025 à 16:29, 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>

Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>

> ---
>   arch/powerpc/platforms/512x/mpc512x_lpbfifo.c | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
> index 9668b052cd4b..f251e0f68262 100644
> --- a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
> +++ b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
> @@ -240,10 +240,8 @@ static int mpc512x_lpbfifo_kick(void)
>          dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
>
>          /* Make DMA channel work with LPB FIFO data register */
> -       if (dma_dev->device_config(lpbfifo.chan, &dma_conf)) {
> -               ret = -EINVAL;
> -               goto err_dma_prep;
> -       }
> +       if (dma_dev->device_config(lpbfifo.chan, &dma_conf))
> +               return -EINVAL;
>
>          sg_init_table(&sg, 1);
>
> --
> 2.43.0