Commit 279c3a2a authored by Dan Carpenter's avatar Dan Carpenter Committed by Jonathan Cameron
Browse files

iio: adc: palmas: fix off by one bugs 



Valid values for "adc_chan" are zero to (PALMAS_ADC_CH_MAX - 1).
Smatch detects some buffer overflows caused by this:
drivers/iio/adc/palmas_gpadc.c:721 palmas_gpadc_read_event_value() error: buffer overflow 'adc->thresholds' 16 <= 16
drivers/iio/adc/palmas_gpadc.c:758 palmas_gpadc_write_event_value() error: buffer overflow 'adc->thresholds' 16 <= 16

The effect of this bug in other functions is more complicated but
obviously we should fix all of them.

Fixes: a99544c6 ("iio: adc: palmas: add support for iio threshold events")
Signed-off-by: default avatarDan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/14fee94a-7db7-4371-b7d6-e94d86b9561e@kili.mountain


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 27b2ed5b

drivers/iio/adc/palmas_gpadc.c

+5 −5
Original line number Diff line number Diff line
@@ -547,7 +547,7 @@ static int palmas_gpadc_read_raw(struct iio_dev *indio_dev, 
	int adc_chan = chan->channel;

	int ret = 0;



	if (adc_chan > PALMAS_ADC_CH_MAX)

	if (adc_chan >= PALMAS_ADC_CH_MAX)

		return -EINVAL;



	mutex_lock(&adc->lock);
@@ -595,7 +595,7 @@ static int palmas_gpadc_read_event_config(struct iio_dev *indio_dev, 
	int adc_chan = chan->channel;

	int ret = 0;



	if (adc_chan > PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)

	if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)

		return -EINVAL;



	mutex_lock(&adc->lock);
@@ -684,7 +684,7 @@ static int palmas_gpadc_write_event_config(struct iio_dev *indio_dev, 
	int adc_chan = chan->channel;

	int ret;



	if (adc_chan > PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)

	if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)

		return -EINVAL;



	mutex_lock(&adc->lock);
@@ -710,7 +710,7 @@ static int palmas_gpadc_read_event_value(struct iio_dev *indio_dev, 
	int adc_chan = chan->channel;

	int ret;



	if (adc_chan > PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)

	if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)

		return -EINVAL;



	mutex_lock(&adc->lock);
@@ -744,7 +744,7 @@ static int palmas_gpadc_write_event_value(struct iio_dev *indio_dev, 
	int old;

	int ret;



	if (adc_chan > PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)

	if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)

		return -EINVAL;



	mutex_lock(&adc->lock);