| Message ID | 1652939455-123139-1-git-send-email-lyz_cs@pku.edu.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] iio: vadc: Fix potential dereference of NULL pointer | expand |
On Wed, 18 May 2022 22:50:55 -0700 Yongzhi Liu <lyz_cs@pku.edu.cn> wrote: > The return value of vadc_get_channel() needs to be checked > to avoid use of NULL pointer. Fix this by adding the null > pointer check on prop. > > Fixes: 0917de94c ("iio: vadc: Qualcomm SPMI PMIC voltage ADC driver") > > Signed-off-by: Yongzhi Liu <lyz_cs@pku.edu.cn> This function has a lot of goto err; where err just results in a print. My suggestion is to just drop that print and use error specific prints as you have done here, then use direct returns. > --- > drivers/iio/adc/qcom-spmi-vadc.c | 23 ++++++++++++++++++++++- > 1 file changed, 22 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c > index 34202ba..9fa61fb 100644 > --- a/drivers/iio/adc/qcom-spmi-vadc.c > +++ b/drivers/iio/adc/qcom-spmi-vadc.c > @@ -358,14 +358,25 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc) > vadc->graph[VADC_CALIB_ABSOLUTE].dx = VADC_ABSOLUTE_RANGE_UV; > > prop = vadc_get_channel(vadc, VADC_REF_1250MV); > + if (!prop) { > + dev_err(vadc->dev, "Please define 1.25V channel\n"); > + ret = -ENODEV; > + goto err; > + } > ret = vadc_do_conversion(vadc, prop, &read_1); > if (ret) > goto err; > > /* Try with buffered 625mV channel first */ > prop = vadc_get_channel(vadc, VADC_SPARE1); > - if (!prop) > + if (!prop) { > prop = vadc_get_channel(vadc, VADC_REF_625MV); > + if (!prop) { > + dev_err(vadc->dev, "Please define 0.625V channel\n"); > + ret = -ENODEV; > + goto err; > + } > + } > > ret = vadc_do_conversion(vadc, prop, &read_2); > if (ret) > @@ -381,11 +392,21 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc) > > /* Ratiometric calibration */ > prop = vadc_get_channel(vadc, VADC_VDD_VADC); > + if (!prop) { > + dev_err(vadc->dev, "Please define VDD channel\n"); > + ret = -ENODEV; > + goto err; > + } > ret = vadc_do_conversion(vadc, prop, &read_1); > if (ret) > goto err; > > prop = vadc_get_channel(vadc, VADC_GND_REF); > + if (!prop) { > + dev_err(vadc->dev, "Please define GND channel\n"); > + ret = -ENODEV; > + goto err; > + } > ret = vadc_do_conversion(vadc, prop, &read_2); > if (ret) > goto err;
diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c index 34202ba..9fa61fb 100644 --- a/drivers/iio/adc/qcom-spmi-vadc.c +++ b/drivers/iio/adc/qcom-spmi-vadc.c @@ -358,14 +358,25 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc) vadc->graph[VADC_CALIB_ABSOLUTE].dx = VADC_ABSOLUTE_RANGE_UV; prop = vadc_get_channel(vadc, VADC_REF_1250MV); + if (!prop) { + dev_err(vadc->dev, "Please define 1.25V channel\n"); + ret = -ENODEV; + goto err; + } ret = vadc_do_conversion(vadc, prop, &read_1); if (ret) goto err; /* Try with buffered 625mV channel first */ prop = vadc_get_channel(vadc, VADC_SPARE1); - if (!prop) + if (!prop) { prop = vadc_get_channel(vadc, VADC_REF_625MV); + if (!prop) { + dev_err(vadc->dev, "Please define 0.625V channel\n"); + ret = -ENODEV; + goto err; + } + } ret = vadc_do_conversion(vadc, prop, &read_2); if (ret) @@ -381,11 +392,21 @@ static int vadc_measure_ref_points(struct vadc_priv *vadc) /* Ratiometric calibration */ prop = vadc_get_channel(vadc, VADC_VDD_VADC); + if (!prop) { + dev_err(vadc->dev, "Please define VDD channel\n"); + ret = -ENODEV; + goto err; + } ret = vadc_do_conversion(vadc, prop, &read_1); if (ret) goto err; prop = vadc_get_channel(vadc, VADC_GND_REF); + if (!prop) { + dev_err(vadc->dev, "Please define GND channel\n"); + ret = -ENODEV; + goto err; + } ret = vadc_do_conversion(vadc, prop, &read_2); if (ret) goto err;
The return value of vadc_get_channel() needs to be checked to avoid use of NULL pointer. Fix this by adding the null pointer check on prop. Fixes: 0917de94c ("iio: vadc: Qualcomm SPMI PMIC voltage ADC driver") Signed-off-by: Yongzhi Liu <lyz_cs@pku.edu.cn> --- drivers/iio/adc/qcom-spmi-vadc.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-)