[PATCH v1] staging: greybus: audio: fix uninitialized value issue

[PATCH v1] staging: greybus: audio: fix uninitialized value issue

[Vaibhav Agarwal]

The current implementation for gbcodec_mixer_dapm_ctl_put() uses
uninitialized gbvalue for comparison with updated value. This was found
using static analysis with coverity.

Uninitialized scalar variable (UNINIT)
11. uninit_use: Using uninitialized value
gbvalue.value.integer_value[0].
460        if (gbvalue.value.integer_value[0] != val) {

This patch fixes the issue with fetching the gbvalue before using it for
comparision.

Fixes: 6339d2322c47 ("greybus: audio: Add topology parser for GB codec")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Vaibhav Agarwal <vaibhav.sr@gmail.com>
---
 drivers/staging/greybus/audio_topology.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/greybus/audio_topology.c b/drivers/staging/greybus/audio_topology.c
index 2f9fdbdcd547..4b914d0edef2 100644
--- a/drivers/staging/greybus/audio_topology.c
+++ b/drivers/staging/greybus/audio_topology.c
@@ -456,6 +456,13 @@ static int gbcodec_mixer_dapm_ctl_put(struct snd_kcontrol *kcontrol,
 	val = ucontrol->value.integer.value[0] & mask;
 	connect = !!val;
 
+	ret = gb_pm_runtime_get_sync(bundle);
+	if (ret)
+		return ret;
+
+	ret = gb_audio_gb_get_control(module->mgmt_connection, data->ctl_id,
+				      GB_AUDIO_INVALID_INDEX, &gbvalue);
+
 	/* update ucontrol */
 	if (gbvalue.value.integer_value[0] != val) {
 		for (wi = 0; wi < wlist->num_widgets; wi++) {
@@ -466,16 +473,10 @@ static int gbcodec_mixer_dapm_ctl_put(struct snd_kcontrol *kcontrol,
 		gbvalue.value.integer_value[0] =
 			cpu_to_le32(ucontrol->value.integer.value[0]);
 
-		ret = gb_pm_runtime_get_sync(bundle);
-		if (ret)
-			return ret;
-
 		ret = gb_audio_gb_set_control(module->mgmt_connection,
 					      data->ctl_id,
 					      GB_AUDIO_INVALID_INDEX, &gbvalue);
 
-		gb_pm_runtime_put_autosuspend(bundle);
-
 		if (ret) {
 			dev_err_ratelimited(codec_dev,
 					    "%d:Error in %s for %s\n", ret,
@@ -483,6 +484,7 @@ static int gbcodec_mixer_dapm_ctl_put(struct snd_kcontrol *kcontrol,
 			return ret;
 		}
 	}
+	gb_pm_runtime_put_autosuspend(bundle);
 
 	return 0;
 }

base-commit: 5bbd90550da8f7bdac769b5825597e67183c9411
prerequisite-patch-id: 2b8901339222ff7b94f10cf2341734c0fb82591c
prerequisite-patch-id: 38dad8879a2b73bce6e89481973c7c5b82bd7145
prerequisite-patch-id: 5f0042ccedae292395ec617789be6bf465463c1c
prerequisite-patch-id: 35d001c366dfa4b567e59abbb37bd691a18f5e14
prerequisite-patch-id: f13ce918ebc3796cd3c81716a7b2adf4519e7387
prerequisite-patch-id: 0fcc6d38699a9b72ca94280d7a4dc18f0823b6f7
prerequisite-patch-id: 8074e935bdc3dd7b114245b0648552d0ff6871c9
-- 
2.27.0

Re: [PATCH v1] staging: greybus: audio: fix uninitialized value issue

[Dan Carpenter]

On Thu, Aug 06, 2020 at 09:51:57PM +0530, Vaibhav Agarwal wrote:
> diff --git a/drivers/staging/greybus/audio_topology.c b/drivers/staging/greybus/audio_topology.c
> index 2f9fdbdcd547..4b914d0edef2 100644
> --- a/drivers/staging/greybus/audio_topology.c
> +++ b/drivers/staging/greybus/audio_topology.c
> @@ -456,6 +456,13 @@ static int gbcodec_mixer_dapm_ctl_put(struct snd_kcontrol *kcontrol,
>  	val = ucontrol->value.integer.value[0] & mask;
>  	connect = !!val;
>  
> +	ret = gb_pm_runtime_get_sync(bundle);
> +	if (ret)
> +		return ret;
> +
> +	ret = gb_audio_gb_get_control(module->mgmt_connection, data->ctl_id,
> +				      GB_AUDIO_INVALID_INDEX, &gbvalue);


We need to check "ret" after this.

> +
>  	/* update ucontrol */
>  	if (gbvalue.value.integer_value[0] != val) {
>  		for (wi = 0; wi < wlist->num_widgets; wi++) {
> @@ -466,16 +473,10 @@ static int gbcodec_mixer_dapm_ctl_put(struct snd_kcontrol *kcontrol,

regards,
dan carpenter

Re: [PATCH v1] staging: greybus: audio: fix uninitialized value issue

[Vaibhav Agarwal]

On Mon, Aug 10, 2020 at 8:34 PM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> On Thu, Aug 06, 2020 at 09:51:57PM +0530, Vaibhav Agarwal wrote:
> > diff --git a/drivers/staging/greybus/audio_topology.c b/drivers/staging/greybus/audio_topology.c
> > index 2f9fdbdcd547..4b914d0edef2 100644
> > --- a/drivers/staging/greybus/audio_topology.c
> > +++ b/drivers/staging/greybus/audio_topology.c
> > @@ -456,6 +456,13 @@ static int gbcodec_mixer_dapm_ctl_put(struct snd_kcontrol *kcontrol,
> >       val = ucontrol->value.integer.value[0] & mask;
> >       connect = !!val;
> >
> > +     ret = gb_pm_runtime_get_sync(bundle);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = gb_audio_gb_get_control(module->mgmt_connection, data->ctl_id,
> > +                                   GB_AUDIO_INVALID_INDEX, &gbvalue);
>
>
> We need to check "ret" after this.

Oops, my bad. Thanks Dan for reporting this. I'll share an updated patch soon.

--
regards,
vaibhav
>
> > +
> >       /* update ucontrol */
> >       if (gbvalue.value.integer_value[0] != val) {
> >               for (wi = 0; wi < wlist->num_widgets; wi++) {
> > @@ -466,16 +473,10 @@ static int gbcodec_mixer_dapm_ctl_put(struct snd_kcontrol *kcontrol,
>
> regards,
> dan carpenter
>