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authorTakashi Iwai <tiwai@suse.de>2019-08-22 16:41:56 +0300
committerTakashi Iwai <tiwai@suse.de>2019-08-22 16:42:03 +0300
commit744f51e863462192727f9118642563d46fa81393 (patch)
tree43e87ed54550a523396283f126d81907e5c4e524 /sound/usb/mixer.c
parent051c78af14fcd74a22b5af45548ad9d588247cc7 (diff)
parentb8e4f1fdfa422398c2d6c47bfb7d1feb3046d70a (diff)
downloadlinux-744f51e863462192727f9118642563d46fa81393.tar.xz
Merge branch 'topic/usb-validation' into for-next
Pull USB validation patches. It's based on the latest 5.3 development branch, so we shall catch up the whole things. Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/mixer.c')
-rw-r--r--sound/usb/mixer.c306
1 files changed, 132 insertions, 174 deletions
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 7b51ab4c35b0..a0468c4a6326 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -68,6 +68,7 @@ struct mixer_build {
unsigned char *buffer;
unsigned int buflen;
DECLARE_BITMAP(unitbitmap, MAX_ID_ELEMS);
+ DECLARE_BITMAP(termbitmap, MAX_ID_ELEMS);
struct usb_audio_term oterm;
const struct usbmix_name_map *map;
const struct usbmix_selector_map *selector_map;
@@ -738,12 +739,6 @@ static int uac_mixer_unit_get_channels(struct mixer_build *state,
struct uac_mixer_unit_descriptor *desc)
{
int mu_channels;
- void *c;
-
- if (desc->bLength < sizeof(*desc))
- return -EINVAL;
- if (!desc->bNrInPins)
- return -EINVAL;
switch (state->mixer->protocol) {
case UAC_VERSION_1:
@@ -759,13 +754,6 @@ static int uac_mixer_unit_get_channels(struct mixer_build *state,
break;
}
- if (!mu_channels)
- return 0;
-
- c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);
- if (c - (void *)desc + (mu_channels - 1) / 8 >= desc->bLength)
- return 0; /* no bmControls -> skip */
-
return mu_channels;
}
@@ -773,16 +761,27 @@ static int uac_mixer_unit_get_channels(struct mixer_build *state,
* parse the source unit recursively until it reaches to a terminal
* or a branched unit.
*/
-static int check_input_term(struct mixer_build *state, int id,
+static int __check_input_term(struct mixer_build *state, int id,
struct usb_audio_term *term)
{
int protocol = state->mixer->protocol;
int err;
void *p1;
+ unsigned char *hdr;
memset(term, 0, sizeof(*term));
- while ((p1 = find_audio_control_unit(state, id)) != NULL) {
- unsigned char *hdr = p1;
+ for (;;) {
+ /* a loop in the terminal chain? */
+ if (test_and_set_bit(id, state->termbitmap))
+ return -EINVAL;
+
+ p1 = find_audio_control_unit(state, id);
+ if (!p1)
+ break;
+ if (!snd_usb_validate_audio_desc(p1, protocol))
+ break; /* bad descriptor */
+
+ hdr = p1;
term->id = id;
if (protocol == UAC_VERSION_1 || protocol == UAC_VERSION_2) {
@@ -800,7 +799,7 @@ static int check_input_term(struct mixer_build *state, int id,
/* call recursively to verify that the
* referenced clock entity is valid */
- err = check_input_term(state, d->bCSourceID, term);
+ err = __check_input_term(state, d->bCSourceID, term);
if (err < 0)
return err;
@@ -834,7 +833,7 @@ static int check_input_term(struct mixer_build *state, int id,
case UAC2_CLOCK_SELECTOR: {
struct uac_selector_unit_descriptor *d = p1;
/* call recursively to retrieve the channel info */
- err = check_input_term(state, d->baSourceID[0], term);
+ err = __check_input_term(state, d->baSourceID[0], term);
if (err < 0)
return err;
term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */
@@ -897,7 +896,7 @@ static int check_input_term(struct mixer_build *state, int id,
/* call recursively to verify that the
* referenced clock entity is valid */
- err = check_input_term(state, d->bCSourceID, term);
+ err = __check_input_term(state, d->bCSourceID, term);
if (err < 0)
return err;
@@ -948,7 +947,7 @@ static int check_input_term(struct mixer_build *state, int id,
case UAC3_CLOCK_SELECTOR: {
struct uac_selector_unit_descriptor *d = p1;
/* call recursively to retrieve the channel info */
- err = check_input_term(state, d->baSourceID[0], term);
+ err = __check_input_term(state, d->baSourceID[0], term);
if (err < 0)
return err;
term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */
@@ -964,7 +963,7 @@ static int check_input_term(struct mixer_build *state, int id,
return -EINVAL;
/* call recursively to retrieve the channel info */
- err = check_input_term(state, d->baSourceID[0], term);
+ err = __check_input_term(state, d->baSourceID[0], term);
if (err < 0)
return err;
@@ -982,6 +981,15 @@ static int check_input_term(struct mixer_build *state, int id,
return -ENODEV;
}
+
+static int check_input_term(struct mixer_build *state, int id,
+ struct usb_audio_term *term)
+{
+ memset(term, 0, sizeof(*term));
+ memset(state->termbitmap, 0, sizeof(state->termbitmap));
+ return __check_input_term(state, id, term);
+}
+
/*
* Feature Unit
*/
@@ -1011,10 +1019,15 @@ static struct usb_feature_control_info audio_feature_info[] = {
{ 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;
}
@@ -1537,7 +1550,7 @@ static void __build_feature_ctl(struct usb_mixer_interface *mixer,
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)
@@ -1570,7 +1583,7 @@ static void __build_feature_ctl(struct usb_mixer_interface *mixer,
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;
@@ -1740,7 +1753,7 @@ static void build_connector_control(struct usb_mixer_interface *mixer,
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,
@@ -1761,13 +1774,6 @@ static int parse_clock_source_unit(struct mixer_build *state, int unitid,
if (state->mixer->protocol != UAC_VERSION_2)
return -EINVAL;
- if (hdr->bLength != sizeof(*hdr)) {
- usb_audio_dbg(state->chip,
- "Bogus clock source descriptor length of %d, ignoring.\n",
- hdr->bLength);
- return 0;
- }
-
/*
* The only property of this unit we are interested in is the
* clock source validity. If that isn't readable, just bail out.
@@ -1793,7 +1799,7 @@ static int parse_clock_source_unit(struct mixer_build *state, int unitid,
kctl = snd_ctl_new1(&usb_bool_master_control_ctl_ro, cval);
if (!kctl) {
- kfree(cval);
+ usb_mixer_elem_info_free(cval);
return -ENOMEM;
}
@@ -1826,62 +1832,20 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
__u8 *bmaControls;
if (state->mixer->protocol == UAC_VERSION_1) {
- if (hdr->bLength < 7) {
- usb_audio_err(state->chip,
- "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
- unitid);
- return -EINVAL;
- }
csize = hdr->bControlSize;
- if (!csize) {
- usb_audio_dbg(state->chip,
- "unit %u: invalid bControlSize == 0\n",
- unitid);
- return -EINVAL;
- }
channels = (hdr->bLength - 7) / csize - 1;
bmaControls = hdr->bmaControls;
- if (hdr->bLength < 7 + csize) {
- usb_audio_err(state->chip,
- "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
- unitid);
- return -EINVAL;
- }
} else if (state->mixer->protocol == UAC_VERSION_2) {
struct uac2_feature_unit_descriptor *ftr = _ftr;
- if (hdr->bLength < 6) {
- usb_audio_err(state->chip,
- "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
- unitid);
- return -EINVAL;
- }
csize = 4;
channels = (hdr->bLength - 6) / 4 - 1;
bmaControls = ftr->bmaControls;
- if (hdr->bLength < 6 + csize) {
- usb_audio_err(state->chip,
- "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
- unitid);
- return -EINVAL;
- }
} else { /* UAC_VERSION_3 */
struct uac3_feature_unit_descriptor *ftr = _ftr;
- if (hdr->bLength < 7) {
- usb_audio_err(state->chip,
- "unit %u: invalid UAC3_FEATURE_UNIT descriptor\n",
- unitid);
- return -EINVAL;
- }
csize = 4;
channels = (ftr->bLength - 7) / 4 - 1;
bmaControls = ftr->bmaControls;
- if (hdr->bLength < 7 + csize) {
- usb_audio_err(state->chip,
- "unit %u: invalid UAC3_FEATURE_UNIT descriptor\n",
- unitid);
- return -EINVAL;
- }
}
/* parse the source unit */
@@ -1988,6 +1952,31 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
* Mixer Unit
*/
+/* check whether the given in/out overflows bmMixerControls matrix */
+static bool mixer_bitmap_overflow(struct uac_mixer_unit_descriptor *desc,
+ int protocol, int num_ins, int num_outs)
+{
+ u8 *hdr = (u8 *)desc;
+ u8 *c = uac_mixer_unit_bmControls(desc, protocol);
+ size_t rest; /* remaining bytes after bmMixerControls */
+
+ switch (protocol) {
+ case UAC_VERSION_1:
+ default:
+ rest = 1; /* iMixer */
+ break;
+ case UAC_VERSION_2:
+ rest = 2; /* bmControls + iMixer */
+ break;
+ case UAC_VERSION_3:
+ rest = 6; /* bmControls + wMixerDescrStr */
+ break;
+ }
+
+ /* overflow? */
+ return c + (num_ins * num_outs + 7) / 8 + rest > hdr + hdr[0];
+}
+
/*
* build a mixer unit control
*
@@ -2030,7 +2019,7 @@ static void build_mixer_unit_ctl(struct mixer_build *state,
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;
@@ -2056,15 +2045,11 @@ static int parse_audio_input_terminal(struct mixer_build *state, int unitid,
if (state->mixer->protocol == UAC_VERSION_2) {
struct uac2_input_terminal_descriptor *d_v2 = raw_desc;
- if (d_v2->bLength < sizeof(*d_v2))
- return -EINVAL;
control = UAC2_TE_CONNECTOR;
term_id = d_v2->bTerminalID;
bmctls = le16_to_cpu(d_v2->bmControls);
} else if (state->mixer->protocol == UAC_VERSION_3) {
struct uac3_input_terminal_descriptor *d_v3 = raw_desc;
- if (d_v3->bLength < sizeof(*d_v3))
- return -EINVAL;
control = UAC3_TE_INSERTION;
term_id = d_v3->bTerminalID;
bmctls = le32_to_cpu(d_v3->bmControls);
@@ -2116,6 +2101,9 @@ static int parse_audio_mixer_unit(struct mixer_build *state, int unitid,
if (err < 0)
return err;
num_ins += iterm.channels;
+ if (mixer_bitmap_overflow(desc, state->mixer->protocol,
+ num_ins, num_outs))
+ break;
for (; ich < num_ins; ich++) {
int och, ich_has_controls = 0;
@@ -2323,18 +2311,7 @@ static int build_audio_procunit(struct mixer_build *state, int unitid,
const char *name = extension_unit ?
"Extension Unit" : "Processing Unit";
- if (desc->bLength < 13) {
- usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid);
- return -EINVAL;
- }
-
num_ins = desc->bNrInPins;
- if (desc->bLength < 13 + num_ins ||
- desc->bLength < num_ins + uac_processing_unit_bControlSize(desc, state->mixer->protocol)) {
- usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid);
- return -EINVAL;
- }
-
for (i = 0; i < num_ins; i++) {
err = parse_audio_unit(state, desc->baSourceID[i]);
if (err < 0)
@@ -2425,7 +2402,7 @@ static int build_audio_procunit(struct mixer_build *state, int unitid,
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;
@@ -2563,7 +2540,7 @@ static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
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) {
@@ -2589,13 +2566,6 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
const struct usbmix_name_map *map;
char **namelist;
- if (desc->bLength < 5 || !desc->bNrInPins ||
- desc->bLength < 5 + desc->bNrInPins) {
- usb_audio_err(state->chip,
- "invalid SELECTOR UNIT descriptor %d\n", unitid);
- return -EINVAL;
- }
-
for (i = 0; i < desc->bNrInPins; i++) {
err = parse_audio_unit(state, desc->baSourceID[i]);
if (err < 0)
@@ -2635,10 +2605,10 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
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++) {
@@ -2646,11 +2616,8 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
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);
@@ -2664,10 +2631,8 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
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;
@@ -2714,6 +2679,14 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
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;
}
/*
@@ -2734,62 +2707,50 @@ static int parse_audio_unit(struct mixer_build *state, int unitid)
return -EINVAL;
}
- if (protocol == UAC_VERSION_1 || protocol == UAC_VERSION_2) {
- switch (p1[2]) {
- case UAC_INPUT_TERMINAL:
- return parse_audio_input_terminal(state, unitid, p1);
- case UAC_MIXER_UNIT:
- return parse_audio_mixer_unit(state, unitid, p1);
- case UAC2_CLOCK_SOURCE:
- return parse_clock_source_unit(state, unitid, p1);
- case UAC_SELECTOR_UNIT:
- case UAC2_CLOCK_SELECTOR:
- return parse_audio_selector_unit(state, unitid, p1);
- case UAC_FEATURE_UNIT:
- return parse_audio_feature_unit(state, unitid, p1);
- case UAC1_PROCESSING_UNIT:
- /* UAC2_EFFECT_UNIT has the same value */
- if (protocol == UAC_VERSION_1)
- return parse_audio_processing_unit(state, unitid, p1);
- else
- return 0; /* FIXME - effect units not implemented yet */
- case UAC1_EXTENSION_UNIT:
- /* UAC2_PROCESSING_UNIT_V2 has the same value */
- if (protocol == UAC_VERSION_1)
- return parse_audio_extension_unit(state, unitid, p1);
- else /* UAC_VERSION_2 */
- return parse_audio_processing_unit(state, unitid, p1);
- case UAC2_EXTENSION_UNIT_V2:
- return parse_audio_extension_unit(state, unitid, p1);
- default:
- usb_audio_err(state->chip,
- "unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
- return -EINVAL;
- }
- } else { /* UAC_VERSION_3 */
- switch (p1[2]) {
- case UAC_INPUT_TERMINAL:
- return parse_audio_input_terminal(state, unitid, p1);
- case UAC3_MIXER_UNIT:
- return parse_audio_mixer_unit(state, unitid, p1);
- case UAC3_CLOCK_SOURCE:
- return parse_clock_source_unit(state, unitid, p1);
- case UAC3_SELECTOR_UNIT:
- case UAC3_CLOCK_SELECTOR:
- return parse_audio_selector_unit(state, unitid, p1);
- case UAC3_FEATURE_UNIT:
- return parse_audio_feature_unit(state, unitid, p1);
- case UAC3_EFFECT_UNIT:
- return 0; /* FIXME - effect units not implemented yet */
- case UAC3_PROCESSING_UNIT:
- return parse_audio_processing_unit(state, unitid, p1);
- case UAC3_EXTENSION_UNIT:
- return parse_audio_extension_unit(state, unitid, p1);
- default:
- usb_audio_err(state->chip,
- "unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
- return -EINVAL;
- }
+ if (!snd_usb_validate_audio_desc(p1, protocol)) {
+ usb_audio_dbg(state->chip, "invalid unit %d\n", unitid);
+ return 0; /* skip invalid unit */
+ }
+
+#define PTYPE(a, b) ((a) << 8 | (b))
+ switch (PTYPE(protocol, p1[2])) {
+ case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):
+ case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):
+ case PTYPE(UAC_VERSION_3, UAC_INPUT_TERMINAL):
+ return parse_audio_input_terminal(state, unitid, p1);
+ case PTYPE(UAC_VERSION_1, UAC_MIXER_UNIT):
+ case PTYPE(UAC_VERSION_2, UAC_MIXER_UNIT):
+ case PTYPE(UAC_VERSION_3, UAC3_MIXER_UNIT):
+ return parse_audio_mixer_unit(state, unitid, p1);
+ case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SOURCE):
+ case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SOURCE):
+ return parse_clock_source_unit(state, unitid, p1);
+ case PTYPE(UAC_VERSION_1, UAC_SELECTOR_UNIT):
+ case PTYPE(UAC_VERSION_2, UAC_SELECTOR_UNIT):
+ case PTYPE(UAC_VERSION_3, UAC3_SELECTOR_UNIT):
+ case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SELECTOR):
+ case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SELECTOR):
+ return parse_audio_selector_unit(state, unitid, p1);
+ case PTYPE(UAC_VERSION_1, UAC_FEATURE_UNIT):
+ case PTYPE(UAC_VERSION_2, UAC_FEATURE_UNIT):
+ case PTYPE(UAC_VERSION_3, UAC3_FEATURE_UNIT):
+ return parse_audio_feature_unit(state, unitid, p1);
+ case PTYPE(UAC_VERSION_1, UAC1_PROCESSING_UNIT):
+ case PTYPE(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2):
+ case PTYPE(UAC_VERSION_3, UAC3_PROCESSING_UNIT):
+ return parse_audio_processing_unit(state, unitid, p1);
+ case PTYPE(UAC_VERSION_1, UAC1_EXTENSION_UNIT):
+ case PTYPE(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2):
+ case PTYPE(UAC_VERSION_3, UAC3_EXTENSION_UNIT):
+ return parse_audio_extension_unit(state, unitid, p1);
+ case PTYPE(UAC_VERSION_2, UAC2_EFFECT_UNIT):
+ case PTYPE(UAC_VERSION_3, UAC3_EFFECT_UNIT):
+ return 0; /* FIXME - effect units not implemented yet */
+ default:
+ usb_audio_err(state->chip,
+ "unit %u: unexpected type 0x%02x\n",
+ unitid, p1[2]);
+ return -EINVAL;
}
}
@@ -3104,11 +3065,12 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
while ((p = snd_usb_find_csint_desc(mixer->hostif->extra,
mixer->hostif->extralen,
p, UAC_OUTPUT_TERMINAL)) != NULL) {
+ if (!snd_usb_validate_audio_desc(p, mixer->protocol))
+ continue; /* skip invalid descriptor */
+
if (mixer->protocol == UAC_VERSION_1) {
struct uac1_output_terminal_descriptor *desc = p;
- if (desc->bLength < sizeof(*desc))
- continue; /* invalid descriptor? */
/* mark terminal ID as visited */
set_bit(desc->bTerminalID, state.unitbitmap);
state.oterm.id = desc->bTerminalID;
@@ -3120,8 +3082,6 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
} else if (mixer->protocol == UAC_VERSION_2) {
struct uac2_output_terminal_descriptor *desc = p;
- if (desc->bLength < sizeof(*desc))
- continue; /* invalid descriptor? */
/* mark terminal ID as visited */
set_bit(desc->bTerminalID, state.unitbitmap);
state.oterm.id = desc->bTerminalID;
@@ -3147,8 +3107,6 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
} else { /* UAC_VERSION_3 */
struct uac3_output_terminal_descriptor *desc = p;
- if (desc->bLength < sizeof(*desc))
- continue; /* invalid descriptor? */
/* mark terminal ID as visited */
set_bit(desc->bTerminalID, state.unitbitmap);
state.oterm.id = desc->bTerminalID;