[PATCH] ASoC: dapm: Fix uninitialized variable in snd_soc_dapm_get_enum_double()

From: Geert Uytterhoeven
Date: Fri Aug 08 2014 - 11:29:46 EST


If soc_dapm_read() fails, reg_val will be uninitialized, and bogus
values will be written later:

sound/soc/soc-dapm.c: In function 'snd_soc_dapm_get_enum_double':
sound/soc/soc-dapm.c:2862:15: warning: 'reg_val' may be used uninitialized in this function [-Wmaybe-uninitialized]
unsigned int reg_val, val;
^

Return early on error to fix this.

Introduced by commit ce0fc93ae56e2ba50ff8c220d69e4e860e889320 ("ASoC:
Add DAPM support at the component level").
---
Is this correct? Please review.

Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
sound/soc/soc-dapm.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index 8348352dc2c6..177bd8639ef9 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -2860,12 +2860,14 @@ int snd_soc_dapm_get_enum_double(struct snd_kcontrol *kcontrol,
struct snd_soc_dapm_context *dapm = snd_soc_dapm_kcontrol_dapm(kcontrol);
struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
unsigned int reg_val, val;
- int ret = 0;

- if (e->reg != SND_SOC_NOPM)
- ret = soc_dapm_read(dapm, e->reg, &reg_val);
- else
+ if (e->reg != SND_SOC_NOPM) {
+ int ret = soc_dapm_read(dapm, e->reg, &reg_val);
+ if (ret)
+ return ret;
+ } else {
reg_val = dapm_kcontrol_get_value(kcontrol);
+ }

val = (reg_val >> e->shift_l) & e->mask;
ucontrol->value.enumerated.item[0] = snd_soc_enum_val_to_item(e, val);
@@ -2875,7 +2877,7 @@ int snd_soc_dapm_get_enum_double(struct snd_kcontrol *kcontrol,
ucontrol->value.enumerated.item[1] = val;
}

- return ret;
+ return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_dapm_get_enum_double);

--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/