On Mon, Dec 16, 2024 at 07:26:09PM +0900, Joe Hattori wrote:
> The .probe() of edma_driver calls of_parse_phandle_with_fixed_args() but
> does not release the obtained OF nodes. Thus implement
> edma_cleanup_tc_list(), which releases those OF nodes, and call it in
> the error path of .probe() and in .remove().
>
> This bug was found by an experimental static analysis tool that I am
> developing.
>
> Fixes: 1be5336bc7ba ("dmaengine: edma: New device tree binding")
> Signed-off-by: Joe Hattori <joe@xxxxxxxxxxxxxxxxxxxxx>
> ---
> drivers/dma/ti/edma.c | 23 +++++++++++++++++++----
> 1 file changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/dma/ti/edma.c b/drivers/dma/ti/edma.c
> index 343e986e66e7..e6eee6cfa94a 100644
> --- a/drivers/dma/ti/edma.c
> +++ b/drivers/dma/ti/edma.c
> @@ -2279,6 +2279,18 @@ static struct dma_chan *of_edma_xlate(struct of_phandle_args *dma_spec,
>
> static bool edma_filter_fn(struct dma_chan *chan, void *param);
>
> +static void edma_cleanup_tc_list(struct edma_cc *ecc)
> +{
> + int i;
> +
> + if (!ecc->tc_list)
> + return;
> + for (i = 0; i < ecc->num_tc; i++) {
> + if (ecc->tc_list[i].node)
> + of_node_put(ecc->tc_list[i].node);
No need for this NULL check.
In a way, it would be cleanest to just get rid of the .node struct
member. We never use it. We could just save the .id and call
of_node_put() right away in probe. That's really how it's normally
done.
regards,
dan carpenter
