ASoC: wm_adsp: Use scnprintf() for the limited buffer output

snprintf() is a hard-to-use function, it's especially difficult to use
it for concatenating substrings in a buffer with a limited size.
Since snprintf() returns the would-be-output size, not the actual
size, the subsequent use of snprintf() may point to the incorrect
position.

Use scnprintf() instead for fixing such potential errors.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20200313130334.9028-1-tiwai@suse.de
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/wm_adsp.c b/sound/soc/codecs/wm_adsp.c
index 2a9b610..9e5b6c4 100644 (file)
--- a/sound/soc/codecs/wm_adsp.c
+++ b/sound/soc/codecs/wm_adsp.c
@@ -1432,12 +1432,12 @@ static int wm_adsp_create_control(struct wm_adsp *dsp,
                subname = NULL; /* don't append subname */
                break;
        case 2:
-               ret = snprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN,
+               ret = scnprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN,
                                "%s%c %.12s %x", dsp->name, *region_name,
                                wm_adsp_fw_text[dsp->fw], alg_region->alg);
                break;
        default:
-               ret = snprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN,
+               ret = scnprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN,
                                "%s %.12s %x", dsp->name,
                                wm_adsp_fw_text[dsp->fw], alg_region->alg);
                break;