From: Takashi Iwai <tiwai@suse.de>
Date: Fri, 2 Dec 2011 14:29:12 +0000 (+0100)
Subject: ALSA: hda/realtek - Fix Oops in alc_mux_select()
X-Git-Tag: firefly_0821_release~7541^2~2134
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=2a72a47b80bf4dfbdec91889d1d2c4702f134da5;p=firefly-linux-kernel-4.4.55.git

ALSA: hda/realtek - Fix Oops in alc_mux_select()

commit cce4aa378a049f4275416ee6302dd24f37b289df upstream.

When no imux is available (e.g. a single capture source),
alc_auto_init_input_src() may trigger an Oops due to the access to -1.
Add a proper zero-check to avoid it.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index e7dc0340da62..eb0a141966a0 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -509,6 +509,8 @@ static int alc_mux_enum_put(struct snd_kcontrol *kcontrol,
 	imux = &spec->input_mux[mux_idx];
 	if (!imux->num_items && mux_idx > 0)
 		imux = &spec->input_mux[0];
+	if (!imux->num_items)
+		return 0;
 
 	type = get_wcaps_type(get_wcaps(codec, nid));
 	if (type == AC_WID_AUD_MIX) {