`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We should prefer more robust and less ambiguous string interfaces.
We expect adc->chan_name[val] to be NUL-terminated based on ch_name's
use within functions that expect NUL-terminated strings like strncmp and
printf-likes:
| if (!strncmp(stm32_adc_ic[i].name, ch_name, STM32_ADC_CH_SZ)) {
| /* Check internal channel availability */
| switch (i) {
| case STM32_ADC_INT_CH_VDDCORE:
| if (!adc->cfg->regs->or_vddcore.reg)
| dev_warn(&indio_dev->dev,
| "%s channel not available\n", ch_name);
...
There is no evidence that NUL-padding is needed either.
Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding. If, for any reason, NUL-padding _is_
required we should go for `strscpy_pad`.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@xxxxxxxxxxxxxxx
Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx>
---
Note: build-tested
---
drivers/iio/adc/stm32-adc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
index f7613efb870d..9cdcf396d901 100644
--- a/drivers/iio/adc/stm32-adc.c
+++ b/drivers/iio/adc/stm32-adc.c
@@ -2209,7 +2209,7 @@ static int stm32_adc_generic_chan_init(struct iio_dev *indio_dev,
ret = -EINVAL;
goto err;
}
- strncpy(adc->chan_name[val], name, STM32_ADC_CH_SZ);
+ strscpy(adc->chan_name[val], name, STM32_ADC_CH_SZ);
ret = stm32_adc_populate_int_ch(indio_dev, name, val);
if (ret == -ENOENT)
continue;
---
base-commit: 2cf0f715623872823a72e451243bbf555d10d032
change-id: 20230921-strncpy-drivers-iio-adc-stm32-adc-c-1bf936a4ffbb
Best regards,
--
Justin Stitt <justinstitt@xxxxxxxxxx>
