Re: [PATCH] ASoC: rsnd: don't double free kctrl

From: Kuninori Morimoto
Date: Thu Dec 08 2016 - 19:04:52 EST



Hi Colin

> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> On an error, snd_ctl_add already free's kctrl, so calling snd_ctl_free_one
> to free it again leads to a double free error. Fix this by removing
> the extraneous snd_ctl_free_one call.
>
> Issue found using static analysis with CoverityScan, CID 1372908
>
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---

Indeed...
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>

If my memory was correct, this code was copied from somewhere...

BTW, in my opinion, function parameter automatically freed in "add" function
is a little bit strange behavior for me...

> sound/soc/sh/rcar/core.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c
> index 4bd68de..99b5b08 100644
> --- a/sound/soc/sh/rcar/core.c
> +++ b/sound/soc/sh/rcar/core.c
> @@ -1030,10 +1030,8 @@ static int __rsnd_kctrl_new(struct rsnd_mod *mod,
> return -ENOMEM;
>
> ret = snd_ctl_add(card, kctrl);
> - if (ret < 0) {
> - snd_ctl_free_one(kctrl);
> + if (ret < 0)
> return ret;
> - }
>
> cfg->update = update;
> cfg->card = card;
> --
> 2.10.2
>