| Message ID | 20231201-mcp3564_range_checks-v1-1-68f4436e22b0@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | iio: adc: MCP3564: fix calib_bias and calib_scale range checks | expand |
Hi Javier Carrasco, Thank you for looking over the driver, for spotting and reporting the bug. Your fix is OK. Reviewed-by: Marius Cristea <marius.cristea@microchip.com> Thanks, Marius On Fri, 2023-12-01 at 10:48 +0100, Javier Carrasco wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you > know the content is safe > > The current implementation uses the AND (&&) operator to check if the > value to write for IIO_CHAN_INFO_CALIBBIAS and > IIO_CHAN_INFO_CALIBSCALE > is within the valid ranges. > The evaluated values are the lower and upper limits of the ranges, > so this operation always evaluates to false. > > The OR (||) operator must be used instead. > > Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com> > --- > This bug has been found when looking for use cases of IIO_AVAIL_RANGE > and the fix could not be tested with real hardware. The issue and its > soulution are rather simple, but still some testing and confirmation > would be welcome. > --- > drivers/iio/adc/mcp3564.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/adc/mcp3564.c b/drivers/iio/adc/mcp3564.c > index e3f1de5fcc5a..d5fb1cae8aeb 100644 > --- a/drivers/iio/adc/mcp3564.c > +++ b/drivers/iio/adc/mcp3564.c > @@ -918,7 +918,7 @@ static int mcp3564_write_raw(struct iio_dev > *indio_dev, > mutex_unlock(&adc->lock); > return ret; > case IIO_CHAN_INFO_CALIBBIAS: > - if (val < mcp3564_calib_bias[0] && val > > mcp3564_calib_bias[2]) > + if (val < mcp3564_calib_bias[0] || val > > mcp3564_calib_bias[2]) > return -EINVAL; > > mutex_lock(&adc->lock); > @@ -928,7 +928,7 @@ static int mcp3564_write_raw(struct iio_dev > *indio_dev, > mutex_unlock(&adc->lock); > return ret; > case IIO_CHAN_INFO_CALIBSCALE: > - if (val < mcp3564_calib_scale[0] && val > > mcp3564_calib_scale[2]) > + if (val < mcp3564_calib_scale[0] || val > > mcp3564_calib_scale[2]) > return -EINVAL; > > if (adc->calib_scale == val) > > --- > base-commit: 994d5c58e50e91bb02c7be4a91d5186292a895c8 > change-id: 20231201-mcp3564_range_checks-221708838130 > > Best regards, > -- > Javier Carrasco <javier.carrasco.cruz@gmail.com> >
On Mon, 4 Dec 2023 09:23:45 +0000 <Marius.Cristea@microchip.com> wrote: > Hi Javier Carrasco, > > Thank you for looking over the driver and spotting and reporting the bug. Your fix is OK. > > Reviewed-by: Marius Cristea <marius.cristea@microchip.com> > Applied to the fixes-togreg branch of iio.git and marked for stable. Thanks, Jonathan > Thanks, > Marius > > ________________________________ > From: Javier Carrasco <javier.carrasco.cruz@gmail.com> > Sent: Friday, December 1, 2023 11:48 AM > To: Marius Cristea - M70257 <Marius.Cristea@microchip.com>; Jonathan Cameron <jic23@kernel.org>; Lars-Peter Clausen <lars@metafoo.de> > Cc: linux-iio@vger.kernel.org <linux-iio@vger.kernel.org>; linux-kernel@vger.kernel.org <linux-kernel@vger.kernel.org>; Javier Carrasco <javier.carrasco.cruz@gmail.com> > Subject: [PATCH] iio: adc: MCP3564: fix calib_bias and calib_scale range checks > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > The current implementation uses the AND (&&) operator to check if the > value to write for IIO_CHAN_INFO_CALIBBIAS and IIO_CHAN_INFO_CALIBSCALE > is within the valid ranges. > The evaluated values are the lower and upper limits of the ranges, > so this operation always evaluates to false. > > The OR (||) operator must be used instead. > > Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com> > --- > This bug has been found when looking for use cases of IIO_AVAIL_RANGE > and the fix could not be tested with real hardware. The issue and its > soulution are rather simple, but still some testing and confirmation > would be welcome. > --- > drivers/iio/adc/mcp3564.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/adc/mcp3564.c b/drivers/iio/adc/mcp3564.c > index e3f1de5fcc5a..d5fb1cae8aeb 100644 > --- a/drivers/iio/adc/mcp3564.c > +++ b/drivers/iio/adc/mcp3564.c > @@ -918,7 +918,7 @@ static int mcp3564_write_raw(struct iio_dev *indio_dev, > mutex_unlock(&adc->lock); > return ret; > case IIO_CHAN_INFO_CALIBBIAS: > - if (val < mcp3564_calib_bias[0] && val > mcp3564_calib_bias[2]) > + if (val < mcp3564_calib_bias[0] || val > mcp3564_calib_bias[2]) > return -EINVAL; > > mutex_lock(&adc->lock); > @@ -928,7 +928,7 @@ static int mcp3564_write_raw(struct iio_dev *indio_dev, > mutex_unlock(&adc->lock); > return ret; > case IIO_CHAN_INFO_CALIBSCALE: > - if (val < mcp3564_calib_scale[0] && val > mcp3564_calib_scale[2]) > + if (val < mcp3564_calib_scale[0] || val > mcp3564_calib_scale[2]) > return -EINVAL; > > if (adc->calib_scale == val) > > --- > base-commit: 994d5c58e50e91bb02c7be4a91d5186292a895c8 > change-id: 20231201-mcp3564_range_checks-221708838130 > > Best regards, > -- > Javier Carrasco <javier.carrasco.cruz@gmail.com> >
diff --git a/drivers/iio/adc/mcp3564.c b/drivers/iio/adc/mcp3564.c index e3f1de5fcc5a..d5fb1cae8aeb 100644 --- a/drivers/iio/adc/mcp3564.c +++ b/drivers/iio/adc/mcp3564.c @@ -918,7 +918,7 @@ static int mcp3564_write_raw(struct iio_dev *indio_dev, mutex_unlock(&adc->lock); return ret; case IIO_CHAN_INFO_CALIBBIAS: - if (val < mcp3564_calib_bias[0] && val > mcp3564_calib_bias[2]) + if (val < mcp3564_calib_bias[0] || val > mcp3564_calib_bias[2]) return -EINVAL; mutex_lock(&adc->lock); @@ -928,7 +928,7 @@ static int mcp3564_write_raw(struct iio_dev *indio_dev, mutex_unlock(&adc->lock); return ret; case IIO_CHAN_INFO_CALIBSCALE: - if (val < mcp3564_calib_scale[0] && val > mcp3564_calib_scale[2]) + if (val < mcp3564_calib_scale[0] || val > mcp3564_calib_scale[2]) return -EINVAL; if (adc->calib_scale == val)
The current implementation uses the AND (&&) operator to check if the value to write for IIO_CHAN_INFO_CALIBBIAS and IIO_CHAN_INFO_CALIBSCALE is within the valid ranges. The evaluated values are the lower and upper limits of the ranges, so this operation always evaluates to false. The OR (||) operator must be used instead. Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com> --- This bug has been found when looking for use cases of IIO_AVAIL_RANGE and the fix could not be tested with real hardware. The issue and its soulution are rather simple, but still some testing and confirmation would be welcome. --- drivers/iio/adc/mcp3564.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- base-commit: 994d5c58e50e91bb02c7be4a91d5186292a895c8 change-id: 20231201-mcp3564_range_checks-221708838130 Best regards,