[PATCH 1/4] ASoC: codecs: wcd938x: fix incorrect used of portid

[Srinivas Kandagatla]

Mixer controls have the channel id in mixer->reg, which is not same
as port id. port id should be derived from chan_info array.
So fix this. Without this, its possible that we could corrupt
struct wcd938x_sdw_priv by accessing port_map array out of range
with channel id instead of port id.

Fixes: e8ba1e05bdc0 ("ASoC: codecs: wcd938x: add basic controls")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla at linaro.org>
---
 sound/soc/codecs/wcd938x.c | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/sound/soc/codecs/wcd938x.c b/sound/soc/codecs/wcd938x.c
index eff200a07d9f..5994644c8702 100644
--- a/sound/soc/codecs/wcd938x.c
+++ b/sound/soc/codecs/wcd938x.c
@@ -1432,14 +1432,10 @@ static int wcd938x_sdw_connect_port(struct wcd938x_sdw_ch_info *ch_info,
 	return 0;
 }
 
-static int wcd938x_connect_port(struct wcd938x_sdw_priv *wcd, u8 ch_id, u8 enable)
+static int wcd938x_connect_port(struct wcd938x_sdw_priv *wcd, u8 port_num, u8 ch_id, u8 enable)
 {
-	u8 port_num;
-
-	port_num = wcd->ch_info[ch_id].port_num;
-
 	return wcd938x_sdw_connect_port(&wcd->ch_info[ch_id],
-					&wcd->port_config[port_num],
+					&wcd->port_config[port_num - 1],
 					enable);
 }
 
@@ -2593,6 +2589,7 @@ static int wcd938x_set_compander(struct snd_kcontrol *kcontrol,
 	struct wcd938x_priv *wcd938x = snd_soc_component_get_drvdata(component);
 	struct wcd938x_sdw_priv *wcd;
 	int value = ucontrol->value.integer.value[0];
+	int portidx;
 	struct soc_mixer_control *mc;
 	bool hphr;
 
@@ -2606,10 +2603,12 @@ static int wcd938x_set_compander(struct snd_kcontrol *kcontrol,
 	else
 		wcd938x->comp1_enable = value;
 
+	portidx = wcd->ch_info[mc->reg].port_num;
+
 	if (value)
-		wcd938x_connect_port(wcd, mc->reg, true);
+		wcd938x_connect_port(wcd, portidx, mc->reg, true);
 	else
-		wcd938x_connect_port(wcd, mc->reg, false);
+		wcd938x_connect_port(wcd, portidx, mc->reg, false);
 
 	return 0;
 }
@@ -2882,9 +2881,11 @@ static int wcd938x_get_swr_port(struct snd_kcontrol *kcontrol,
 	struct wcd938x_sdw_priv *wcd;
 	struct soc_mixer_control *mixer = (struct soc_mixer_control *)kcontrol->private_value;
 	int dai_id = mixer->shift;
-	int portidx = mixer->reg;
+	int portidx, ch_idx = mixer->reg;
+
 
 	wcd = wcd938x->sdw_priv[dai_id];
+	portidx = wcd->ch_info[ch_idx].port_num;
 
 	ucontrol->value.integer.value[0] = wcd->port_enable[portidx];
 
@@ -2899,12 +2900,14 @@ static int wcd938x_set_swr_port(struct snd_kcontrol *kcontrol,
 	struct wcd938x_sdw_priv *wcd;
 	struct soc_mixer_control *mixer =
 		(struct soc_mixer_control *)kcontrol->private_value;
-	int portidx = mixer->reg;
+	int ch_idx = mixer->reg;
+	int portidx;
 	int dai_id = mixer->shift;
 	bool enable;
 
 	wcd = wcd938x->sdw_priv[dai_id];
 
+	portidx = wcd->ch_info[ch_idx].port_num;
 	if (ucontrol->value.integer.value[0])
 		enable = true;
 	else
@@ -2912,7 +2915,7 @@ static int wcd938x_set_swr_port(struct snd_kcontrol *kcontrol,
 
 	wcd->port_enable[portidx] = enable;
 
-	wcd938x_connect_port(wcd, portidx, enable);
+	wcd938x_connect_port(wcd, portidx, ch_idx, enable);
 
 	return 0;
 
-- 
2.21.0