[PATCH 1/1] dma: bcm6348: incorrect buffer allocation

[Álvaro Fernández Rojas]

Hello Heinrich,

This is not swapped.
busy_desc is only used in RX. Please, check the rest of the driver:
https://github.com/u-boot/u-boot/blob/master/drivers/dma/bcm6348-iudma.c

Regards,
Álvaro.

El 27/12/2020 a las 10:26, Heinrich Schuchardt escribió:
> Calling calloc() for 0 members does not make any sense.
> Setting ch_priv->busy_desc = NULL for ch_priv->desc_cnt > 0 is equally
> unreasonable.
> 
> The current code will lead to a NULL dereference in bcm6348_iudma_enable().
> 
> The assignments for ch_priv->busy_desc are obviously swapped.
> 
> Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
> ---
> I have no device to actually test the driver.
> ---
>   drivers/dma/bcm6348-iudma.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/dma/bcm6348-iudma.c b/drivers/dma/bcm6348-iudma.c
> index 91172d483c..81597c56a7 100644
> --- a/drivers/dma/bcm6348-iudma.c
> +++ b/drivers/dma/bcm6348-iudma.c
> @@ -313,10 +313,10 @@ static int bcm6348_iudma_request(struct dma *dma)
>   	ch_priv->desc_id = 0;
>   	if (bcm6348_iudma_chan_is_rx(dma->id)) {
>   		ch_priv->desc_cnt = 0;
> -		ch_priv->busy_desc = calloc(ch_priv->desc_cnt, sizeof(bool));
> +		ch_priv->busy_desc = NULL;
>   	} else {
>   		ch_priv->desc_cnt = ch_priv->dma_ring_size;
> -		ch_priv->busy_desc = NULL;
> +		ch_priv->busy_desc = calloc(ch_priv->desc_cnt, sizeof(bool));
>   	}
> 
>   	return 0;
> --
> 2.29.2
>