ALSA: usb-audio: Add check return value for usb_string()

snd_usb_copy_string_desc() returns zero if usb_string() fails.
In case of failure, we need to check the snd_usb_copy_string_desc()'s
return value and add an exception case

Signed-off-by: Jaejoong Kim <climbbb.kim@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Jaejoong Kim 2017-12-04 15:31:49 +09:00 committed by Takashi Iwai
parent 251552a2b0
commit 89b89d121f

View File

@ -2178,13 +2178,14 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
if (len)
;
else if (nameid)
snd_usb_copy_string_desc(state, nameid, kctl->id.name,
len = snd_usb_copy_string_desc(state, nameid, kctl->id.name,
sizeof(kctl->id.name));
else {
else
len = get_term_name(state, &state->oterm,
kctl->id.name, sizeof(kctl->id.name), 0);
if (!len)
strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
if (!len) {
strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR)
append_ctl_name(kctl, " Clock Source");