From 1731a0c492c806ba3678b6c1aa3081a77ca1abb3 Mon Sep 17 00:00:00 2001 From: Justin Stitt Date: Thu, 21 Sep 2023 04:54:00 +0000 Subject: [PATCH] iio: adc: stm32-adc: Replace deprecated strncpy() with strscpy() 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@vger.kernel.org Signed-off-by: Justin Stitt Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20230921-strncpy-drivers-iio-adc-stm32-adc-c-v1-1-c50eca098597@google.com Signed-off-by: Jonathan Cameron --- 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 25a912805439..b5d3c9cea5c4 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;