diff options
| author | Takashi Iwai | 2017-05-30 09:23:41 +0200 |
|---|---|---|
| committer | Takashi Iwai | 2017-05-31 08:46:14 +0200 |
| commit | 64188cfbe5245d412de2139a3864e4e00b4136f0 (patch) | |
| tree | 7551a8af8eb7594e467e6051e96ffdb81b9f02a2 /sound/usb/mixer_us16x08.c | |
| parent | 1fc2e41f7af4572b07190f9dec28396b418e9a36 (diff) | |
Revert "ALSA: usb-audio: purge needless variable length array"
This reverts commit 89b593c30e83 ("ALSA: usb-audio: purge needless
variable length array"). The patch turned out to cause a severe
regression, triggering an Oops at snd_usb_ctl_msg(). It was overseen
that snd_usb_ctl_msg() writes back the response to the given buffer,
while the patch changed it to a read-only const buffer. (One should
always double-check when an extra pointer cast is present...)
As a simple fix, just revert the affected commit. It was merely a
cleanup. Although it brings VLA again, it's clearer as a fix. We'll
address the VLA later in another patch.
Fixes: 89b593c30e83 ("ALSA: usb-audio: purge needless variable length array")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195875
Cc: <stable@vger.kernel.org> # v4.11+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/mixer_us16x08.c')
| -rw-r--r-- | sound/usb/mixer_us16x08.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/sound/usb/mixer_us16x08.c b/sound/usb/mixer_us16x08.c index dc48eedea92e..29d2c9282987 100644 --- a/sound/usb/mixer_us16x08.c +++ b/sound/usb/mixer_us16x08.c @@ -698,12 +698,12 @@ static int snd_us16x08_meter_get(struct snd_kcontrol *kcontrol, struct snd_usb_audio *chip = elem->head.mixer->chip; struct snd_us16x08_meter_store *store = elem->private_data; u8 meter_urb[64]; - char tmp[sizeof(mix_init_msg2)] = {0}; + char tmp[max(sizeof(mix_init_msg1), sizeof(mix_init_msg2))]; switch (kcontrol->private_value) { case 0: - snd_us16x08_send_urb(chip, (char *)mix_init_msg1, - sizeof(mix_init_msg1)); + memcpy(tmp, mix_init_msg1, sizeof(mix_init_msg1)); + snd_us16x08_send_urb(chip, tmp, 4); snd_us16x08_recv_urb(chip, meter_urb, sizeof(meter_urb)); kcontrol->private_value++; @@ -721,7 +721,7 @@ static int snd_us16x08_meter_get(struct snd_kcontrol *kcontrol, case 3: memcpy(tmp, mix_init_msg2, sizeof(mix_init_msg2)); tmp[2] = snd_get_meter_comp_index(store); - snd_us16x08_send_urb(chip, tmp, sizeof(mix_init_msg2)); + snd_us16x08_send_urb(chip, tmp, 10); snd_us16x08_recv_urb(chip, meter_urb, sizeof(meter_urb)); kcontrol->private_value = 0; |