From: Clemens Ladisch Date: Mon, 22 Feb 2010 09:45:07 +0000 (-0300) Subject: V4L/DVB: cx88-alsa: prevent out-of-range volume setting X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=cca80b973244cf7cf721b05b33178ba4826dbc5e;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git V4L/DVB: cx88-alsa: prevent out-of-range volume setting Ensure that volume values are always in the allowed range. Otherwise, it would be possible to set other bits in the AUD_VOL_CTL register or to get a wrong sign in the AUD_BAL_CTL register. Signed-off-by: Clemens Ladisch Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/video/cx88/cx88-alsa.c b/drivers/media/video/cx88/cx88-alsa.c index 5a67445dd6ed..64b350df78e3 100644 --- a/drivers/media/video/cx88/cx88-alsa.c +++ b/drivers/media/video/cx88/cx88-alsa.c @@ -583,16 +583,18 @@ static int snd_cx88_volume_put(struct snd_kcontrol *kcontrol, { snd_cx88_card_t *chip = snd_kcontrol_chip(kcontrol); struct cx88_core *core=chip->core; - int v, b; + int left, right, v, b; int changed = 0; u32 old; - b = value->value.integer.value[1] - value->value.integer.value[0]; + left = value->value.integer.value[0] & 0x3f; + right = value->value.integer.value[1] & 0x3f; + b = right - left; if (b < 0) { - v = 0x3f - value->value.integer.value[0]; + v = 0x3f - left; b = (-b) | 0x40; } else { - v = 0x3f - value->value.integer.value[1]; + v = 0x3f - right; } /* Do we really know this will always be called with IRQs on? */ spin_lock_irq(&chip->reg_lock);