ASoC: codecs: add null check before use

Add null check for swr dmic component and swr_dmic_priv
before use.
Add array bounds check for slave port index before
accessing the array.

Change-Id: I6f1976e98e41e513a9a9db83d4e804a5cb1fe79b
Signed-off-by: Junkai Cai <[email protected]>

asoc/codecs/swr-dmic.c

@@ -132,9 +132,20 @@ static int swr_dmic_tx_master_port_get(struct snd_kcontrol *kcontrol,
 {
 	struct snd_soc_component *component =
 				snd_soc_kcontrol_component(kcontrol);
-	struct swr_dmic_priv *swr_dmic = snd_soc_component_get_drvdata(component);
+	struct swr_dmic_priv *swr_dmic = NULL;
 	int ret = 0;
-	int slave_port_idx;
+	unsigned int slave_port_idx = SWR_DMIC_MAX_PORTS;
+
+	if (NULL == component) {
+		pr_err("%s: swr dmic component is NULL\n", __func__);
+		return -EINVAL;
+	}
+
+	swr_dmic = snd_soc_component_get_drvdata(component);
+	if (NULL == swr_dmic) {
+		pr_err("%s: swr_dmic_priv is NULL\n", __func__);
+		return -EINVAL;
+	}
 
 	ret = swr_dmic_tx_get_slave_port_type_idx(kcontrol->id.name,
 							&slave_port_idx);
@@ -143,6 +154,11 @@ static int swr_dmic_tx_master_port_get(struct snd_kcontrol *kcontrol,
 		return ret;
 	}
 
+	if (slave_port_idx >= SWR_DMIC_MAX_PORTS) {
+		pr_err("%s: invalid slave port id\n", __func__);
+		return -EINVAL;
+	}
+
 	ucontrol->value.integer.value[0] =
 			swr_dmic_get_master_port_val(
 				swr_dmic->tx_master_port_map[slave_port_idx]);
@@ -158,9 +174,21 @@ static int swr_dmic_tx_master_port_put(struct snd_kcontrol *kcontrol,
 {
 	struct snd_soc_component *component =
 				snd_soc_kcontrol_component(kcontrol);
-	struct swr_dmic_priv *swr_dmic = snd_soc_component_get_drvdata(component);
+	struct swr_dmic_priv *swr_dmic = NULL;
 	int ret = 0;
-	unsigned int slave_port_idx = SWR_DMIC_MAX_PORTS, idx = 0;
+	unsigned int slave_port_idx = SWR_DMIC_MAX_PORTS;
+	unsigned int idx = 0;
+
+	if (NULL == component) {
+		pr_err("%s: swr dmic component is NULL\n", __func__);
+		return -EINVAL;
+	}
+
+	swr_dmic = snd_soc_component_get_drvdata(component);
+	if (NULL == swr_dmic) {
+		pr_err("%s: swr_dmic_priv is NULL\n", __func__);
+		return -EINVAL;
+	}
 
 	ret  = swr_dmic_tx_get_slave_port_type_idx(kcontrol->id.name,
 							&slave_port_idx);
@@ -169,6 +197,11 @@ static int swr_dmic_tx_master_port_put(struct snd_kcontrol *kcontrol,
 		return ret;
 	}
 
+	if (slave_port_idx >= SWR_DMIC_MAX_PORTS) {
+		pr_err("%s: invalid slave port id\n", __func__);
+		return -EINVAL;
+	}
+
 	idx = ucontrol->value.enumerated.item[0];
 	if (idx < 0 || idx >= ARRAY_SIZE(swr_master_channel_map))
 		return -EINVAL;