[PATCH] iio: vadc: Fix potential dereference of NULL pointer

[Yongzhi Liu]

The return value of vadc_get_channel() needs to be checked
to avoid use of NULL pointer, which is followed by
the caller 'vadc_do_conversion' of function 'vadc_configure'.
Fix this by adding the null pointer check on prop
in function 'vadc_configure'.

Signed-off-by: Yongzhi Liu <lyz_cs@xxxxxxxxxx>
---
 drivers/iio/adc/qcom-spmi-vadc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c
index 34202ba..d99bd72 100644
--- a/drivers/iio/adc/qcom-spmi-vadc.c
+++ b/drivers/iio/adc/qcom-spmi-vadc.c
@@ -210,6 +210,9 @@ static int vadc_configure(struct vadc_priv *vadc,
 	u8 decimation, mode_ctrl;
 	int ret;
 
+	if (!prop)
+		return -ENODEV;
+
 	/* Mode selection */
 	mode_ctrl = (VADC_OP_MODE_NORMAL << VADC_OP_MODE_SHIFT) |
 		     VADC_ADC_TRIM_EN | VADC_AMUX_TRIM_EN;
-- 
2.7.4