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

commit 89b89d121ffcf8d9546633b98ded9d18b8f75891 upstream.

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>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This commit is contained in:
Jaejoong Kim 2017-12-04 15:31:49 +09:00 committed by syphyr
parent 411ff1659a
commit de421c03f6

View file

@ -2016,12 +2016,14 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid, void
if (len)
;
else if (nameid)
snd_usb_copy_string_desc(state, nameid, kctl->id.name, sizeof(kctl->id.name));
else {
len = snd_usb_copy_string_desc(state, nameid, kctl->id.name,
sizeof(kctl->id.name));
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");