[PATCH 5.3 084/193] ALSA: usb-audio: Unify the release of usb_mixer_elem_info objects

From: Greg Kroah-Hartman
Date: Mon Nov 11 2019 - 13:51:56 EST


From: Takashi Iwai <tiwai@xxxxxxx>

commit 52c3e317a857091fd746e15179a637f32be4d337 upstream.

Instead of the direct kfree() calls, introduce a new local helper to
release the usb_mixer_elem_info object. This will be extended to do
more than a single kfree() in the later patches.

Also, use the standard goto instead of multiple calls in
parse_audio_selector_unit() error paths.

Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/usb/mixer.c | 48 ++++++++++++++++++++++++++++--------------------
1 file changed, 28 insertions(+), 20 deletions(-)

--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -1026,10 +1026,15 @@ static struct usb_feature_control_info a
{ UAC2_FU_PHASE_INVERTER, "Phase Inverter Control", USB_MIXER_BOOLEAN, -1 },
};

+static void usb_mixer_elem_info_free(struct usb_mixer_elem_info *cval)
+{
+ kfree(cval);
+}
+
/* private_free callback */
void snd_usb_mixer_elem_free(struct snd_kcontrol *kctl)
{
- kfree(kctl->private_data);
+ usb_mixer_elem_info_free(kctl->private_data);
kctl->private_data = NULL;
}

@@ -1552,7 +1557,7 @@ static void __build_feature_ctl(struct u

ctl_info = get_feature_control_info(control);
if (!ctl_info) {
- kfree(cval);
+ usb_mixer_elem_info_free(cval);
return;
}
if (mixer->protocol == UAC_VERSION_1)
@@ -1585,7 +1590,7 @@ static void __build_feature_ctl(struct u

if (!kctl) {
usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
- kfree(cval);
+ usb_mixer_elem_info_free(cval);
return;
}
kctl->private_free = snd_usb_mixer_elem_free;
@@ -1755,7 +1760,7 @@ static void build_connector_control(stru
kctl = snd_ctl_new1(&usb_connector_ctl_ro, cval);
if (!kctl) {
usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
- kfree(cval);
+ usb_mixer_elem_info_free(cval);
return;
}
get_connector_control_name(mixer, term, is_input, kctl->id.name,
@@ -1808,7 +1813,7 @@ static int parse_clock_source_unit(struc
kctl = snd_ctl_new1(&usb_bool_master_control_ctl_ro, cval);

if (!kctl) {
- kfree(cval);
+ usb_mixer_elem_info_free(cval);
return -ENOMEM;
}

@@ -2070,7 +2075,7 @@ static void build_mixer_unit_ctl(struct
kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
if (!kctl) {
usb_audio_err(state->chip, "cannot malloc kcontrol\n");
- kfree(cval);
+ usb_mixer_elem_info_free(cval);
return;
}
kctl->private_free = snd_usb_mixer_elem_free;
@@ -2468,7 +2473,7 @@ static int build_audio_procunit(struct m

kctl = snd_ctl_new1(&mixer_procunit_ctl, cval);
if (!kctl) {
- kfree(cval);
+ usb_mixer_elem_info_free(cval);
return -ENOMEM;
}
kctl->private_free = snd_usb_mixer_elem_free;
@@ -2606,7 +2611,7 @@ static void usb_mixer_selector_elem_free
if (kctl->private_data) {
struct usb_mixer_elem_info *cval = kctl->private_data;
num_ins = cval->max;
- kfree(cval);
+ usb_mixer_elem_info_free(cval);
kctl->private_data = NULL;
}
if (kctl->private_value) {
@@ -2678,10 +2683,10 @@ static int parse_audio_selector_unit(str
break;
}

- namelist = kmalloc_array(desc->bNrInPins, sizeof(char *), GFP_KERNEL);
+ namelist = kcalloc(desc->bNrInPins, sizeof(char *), GFP_KERNEL);
if (!namelist) {
- kfree(cval);
- return -ENOMEM;
+ err = -ENOMEM;
+ goto error_cval;
}
#define MAX_ITEM_NAME_LEN 64
for (i = 0; i < desc->bNrInPins; i++) {
@@ -2689,11 +2694,8 @@ static int parse_audio_selector_unit(str
len = 0;
namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
if (!namelist[i]) {
- while (i--)
- kfree(namelist[i]);
- kfree(namelist);
- kfree(cval);
- return -ENOMEM;
+ err = -ENOMEM;
+ goto error_name;
}
len = check_mapped_selector_name(state, unitid, i, namelist[i],
MAX_ITEM_NAME_LEN);
@@ -2707,10 +2709,8 @@ static int parse_audio_selector_unit(str
kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
if (! kctl) {
usb_audio_err(state->chip, "cannot malloc kcontrol\n");
- for (i = 0; i < desc->bNrInPins; i++)
- kfree(namelist[i]);
- kfree(namelist);
- kfree(cval);
+ err = -ENOMEM;
+ goto error_name;
return -ENOMEM;
}
kctl->private_value = (unsigned long)namelist;
@@ -2757,6 +2757,14 @@ static int parse_audio_selector_unit(str
usb_audio_dbg(state->chip, "[%d] SU [%s] items = %d\n",
cval->head.id, kctl->id.name, desc->bNrInPins);
return snd_usb_mixer_add_control(&cval->head, kctl);
+
+ error_name:
+ for (i = 0; i < desc->bNrInPins; i++)
+ kfree(namelist[i]);
+ kfree(namelist);
+ error_cval:
+ usb_mixer_elem_info_free(cval);
+ return err;
}

/*