[PATCH] greybus: audio: ensure module is set to avoid crash on dev_err message

From: Colin King
Date: Fri Sep 23 2016 - 06:25:50 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Currently, if info is null, the dev_err message is dereferencing an
uninitialized module pointer. Instead, initialize module before the
dev_err call to fix this issue.

Found using static analysis with cppcheck:
[drivers/staging/greybus/audio_topology.c:175]: (error)
Uninitialized variable: module

Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/staging/greybus/audio_topology.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/greybus/audio_topology.c b/drivers/staging/greybus/audio_topology.c
index 5eef536..c43a959 100644
--- a/drivers/staging/greybus/audio_topology.c
+++ b/drivers/staging/greybus/audio_topology.c
@@ -171,6 +171,9 @@ static int gbcodec_mixer_ctl_info(struct snd_kcontrol *kcontrol,
data = (struct gbaudio_ctl_pvt *)kcontrol->private_value;
info = (struct gb_audio_ctl_elem_info *)data->info;

+ module = find_gb_module(gbcodec, kcontrol->id.name);
+ if (!module)
+ return -EINVAL;
if (!info) {
dev_err(module->dev, "NULL info for %s\n", uinfo->id.name);
return -EINVAL;
@@ -192,9 +195,6 @@ static int gbcodec_mixer_ctl_info(struct snd_kcontrol *kcontrol,
uinfo->value.enumerated.items = max;
if (uinfo->value.enumerated.item > max - 1)
uinfo->value.enumerated.item = max - 1;
- module = find_gb_module(gbcodec, kcontrol->id.name);
- if (!module)
- return -EINVAL;
name = gbaudio_map_controlid(module, data->ctl_id,
uinfo->value.enumerated.item);
strlcpy(uinfo->value.enumerated.name, name, NAME_SIZE);
--
2.9.3