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 <[email protected]>
---
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 <[email protected]>
Hi Javier Carrasco,
Thank you for looking over the driver, for spotting and reporting
the bug. Your fix is OK.
Reviewed-by: Marius Cristea <[email protected]>
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 <[email protected]>
> ---
> 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 <[email protected]>
>
On Mon, 4 Dec 2023 09:23:45 +0000
<[email protected]> 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 <[email protected]>
>
Applied to the fixes-togreg branch of iio.git and marked for stable.
Thanks,
Jonathan
> Thanks,
> Marius
>
> ________________________________
> From: Javier Carrasco <[email protected]>
> Sent: Friday, December 1, 2023 11:48 AM
> To: Marius Cristea - M70257 <[email protected]>; Jonathan Cameron <[email protected]>; Lars-Peter Clausen <[email protected]>
> Cc: [email protected] <[email protected]>; [email protected] <[email protected]>; Javier Carrasco <[email protected]>
> 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 <[email protected]>
> ---
> 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 <[email protected]>
>