On Sun, Apr 23, 2023 at 02:11:24PM +0100, Jonathan Cameron wrote:
> On Fri, 21 Apr 2023 13:41:56 +0300
> Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
>
> > 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 <dan.carpenter@xxxxxxxxxx>
>
> Looks good to me. Slight shuffle at the moment will delay me applying this.
>
> I'll wait for Linus to pick up Greg's pull request then rebase my fixes branch
> on top of that. Otherwise I make a mess of linux-next ordering and things might
> blow up.
>
> In meantime, Patrik, please take a look.
Sorry for the long delay.
The changes look good to me. I've checked all other uses of adc_chan in the
code and they all seem to be guarded by the checks below.
Best regards
Patrik
>
> Jonathan
>
> > ---
> > ---
> > 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 c1c439215aeb..7dfc9c927a23 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);
>
