Re: [PATCH v2] ALSA: sonicvibes: add error handling for snd_ctl_add

From: Takashi Iwai
Date: Thu Jun 14 2018 - 07:30:30 EST


On Thu, 14 Jun 2018 13:22:18 +0200,
Zhouyang Jia wrote:
>
> When snd_ctl_add fails, the lack of error-handling code may
> cause unexpected results.
>
> This patch adds error-handling code after calling snd_ctl_add.
>
> Signed-off-by: Zhouyang Jia <jiazhouyang09@xxxxxxxxx>
> ---
> v1->v2:
> - Check the return value of snd_sonicvibes_create_gameport.
> ---
> sound/pci/sonicvibes.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/sound/pci/sonicvibes.c b/sound/pci/sonicvibes.c
> index a8abb15..75225b04 100644
> --- a/sound/pci/sonicvibes.c
> +++ b/sound/pci/sonicvibes.c
> @@ -1188,6 +1188,7 @@ SONICVIBES_SINGLE("Joystick Speed", 0, SV_IREG_GAME_PORT, 1, 15, 0);
> static int snd_sonicvibes_create_gameport(struct sonicvibes *sonic)
> {
> struct gameport *gp;
> + int err;
>
> sonic->gameport = gp = gameport_allocate_port();
> if (!gp) {
> @@ -1203,7 +1204,10 @@ static int snd_sonicvibes_create_gameport(struct sonicvibes *sonic)
>
> gameport_register_port(gp);
>
> - snd_ctl_add(sonic->card, snd_ctl_new1(&snd_sonicvibes_game_control, sonic));
> + err = snd_ctl_add(sonic->card,
> + snd_ctl_new1(&snd_sonicvibes_game_control, sonic));
> + if (err < 0)
> + return err;
>
> return 0;
> }
> @@ -1515,7 +1519,10 @@ static int snd_sonic_probe(struct pci_dev *pci,
> return err;
> }
>
> - snd_sonicvibes_create_gameport(sonic);
> + if ((err = snd_sonicvibes_create_gameport(sonic)) < 0) {
> + snd_card_free(card);
> + return err;
> + }

You don't need to inherit the old-fashioned style "if ((err = xxx)"
in a new code. Check what checkpatch.pl complains.


thanks,

Takashi