ALSA: usb - Use strlcat() correctly
Don't pass the advanced position to strlcat() but just gives the buffer
head position so that the max size limit can be checked correctly.
Introduced a new helper function to standaralize strlcat() calls.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/usbmixer.c b/sound/usb/usbmixer.c
index ab5a3ac..9efcfd0 100644
--- a/sound/usb/usbmixer.c
+++ b/sound/usb/usbmixer.c
@@ -898,6 +898,11 @@
* build a feature control
*/
+static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
+{
+ return strlcat(kctl->id.name, str, sizeof(kctl->id.name));
+}
+
static void build_feature_ctl(struct mixer_build *state, unsigned char *desc,
unsigned int ctl_mask, int control,
struct usb_audio_term *iterm, int unitid)
@@ -978,13 +983,13 @@
*/
if (! mapped_name && ! (state->oterm.type >> 16)) {
if ((state->oterm.type & 0xff00) == 0x0100) {
- len = strlcat(kctl->id.name, " Capture", sizeof(kctl->id.name));
+ len = append_ctl_name(kctl, " Capture");
} else {
- len = strlcat(kctl->id.name + len, " Playback", sizeof(kctl->id.name));
+ len = append_ctl_name(kctl, " Playback");
}
}
- strlcat(kctl->id.name + len, control == USB_FEATURE_MUTE ? " Switch" : " Volume",
- sizeof(kctl->id.name));
+ append_ctl_name(kctl, control == USB_FEATURE_MUTE ?
+ " Switch" : " Volume");
if (control == USB_FEATURE_VOLUME) {
kctl->tlv.c = mixer_vol_tlv;
kctl->vd[0].access |=
@@ -1143,7 +1148,7 @@
len = get_term_name(state, iterm, kctl->id.name, sizeof(kctl->id.name), 0);
if (! len)
len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
- strlcat(kctl->id.name + len, " Volume", sizeof(kctl->id.name));
+ append_ctl_name(kctl, " Volume");
snd_printdd(KERN_INFO "[%d] MU [%s] ch = %d, val = %d/%d\n",
cval->id, kctl->id.name, cval->channels, cval->min, cval->max);
@@ -1400,8 +1405,8 @@
if (! len)
strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
}
- strlcat(kctl->id.name, " ", sizeof(kctl->id.name));
- strlcat(kctl->id.name, valinfo->suffix, sizeof(kctl->id.name));
+ append_ctl_name(kctl, " ");
+ append_ctl_name(kctl, valinfo->suffix);
snd_printdd(KERN_INFO "[%d] PU [%s] ch = %d, val = %d/%d\n",
cval->id, kctl->id.name, cval->channels, cval->min, cval->max);
@@ -1610,9 +1615,9 @@
strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
if ((state->oterm.type & 0xff00) == 0x0100)
- strlcat(kctl->id.name, " Capture Source", sizeof(kctl->id.name));
+ append_ctl_name(kctl, " Capture Source");
else
- strlcat(kctl->id.name, " Playback Source", sizeof(kctl->id.name));
+ append_ctl_name(kctl, " Playback Source");
}
snd_printdd(KERN_INFO "[%d] SU [%s] items = %d\n",
