Re: [patch] mailbox: bcm-pdc: potential NULL dereference in pdc_shutdown()

[Rob (William) Rice]

Dan,

The fix looks good to me. Thanks for finding and fixing.

Rob

On 8/4/2016 1:30 AM, Dan Carpenter wrote:
> We can't pass NULL pointers to pdc_ring_free() so I moved the check for
> NULL.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
>
> diff --git a/drivers/mailbox/bcm-pdc-mailbox.c b/drivers/mailbox/bcm-pdc-mailbox.c
> index cbe0c1e..c56d4d0 100644
> --- a/drivers/mailbox/bcm-pdc-mailbox.c
> +++ b/drivers/mailbox/bcm-pdc-mailbox.c
> @@ -1191,10 +1191,11 @@ static void pdc_shutdown(struct mbox_chan *chan)
>   {
>   	struct pdc_state *pdcs = chan->con_priv;
>   
> -	if (pdcs)
> -		dev_dbg(&pdcs->pdev->dev,
> -			"Shutdown mailbox channel for PDC %u", pdcs->pdc_idx);
> +	if (!pdcs)
> +		return;
>   
> +	dev_dbg(&pdcs->pdev->dev,
> +		"Shutdown mailbox channel for PDC %u", pdcs->pdc_idx);
>   	pdc_ring_free(pdcs);
>   }
>