From 279c3a2a5eb2c1054fbe38e5c33be08584229047 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 21 Apr 2023 13:41:56 +0300 Subject: [PATCH] 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: a99544c6c883 ("iio: adc: palmas: add support for iio threshold events") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/14fee94a-7db7-4371-b7d6-e94d86b9561e@kili.mountain Signed-off-by: Jonathan Cameron --- drivers/iio/adc/palmas_gpadc.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/iio/adc/palmas_gpadc.c b/drivers/iio/adc/palmas_gpadc.c index c1c4392..7dfc9c9 100644 --- a/drivers/iio/adc/palmas_gpadc.c +++ b/drivers/iio/adc/palmas_gpadc.c @@ -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); -- 2.7.4