`strncpy` is deprecated for use on NUL-terminated destination strings [1]. We should prefer more robust and less ambiguous string interfaces.
A suitable replacement is `strscpy_pad` [2] due to the fact that it guarantees NUL-termination on the destination buffer whilst maintaining the NUL-padding behavior that `strncpy` provides. This may not be strictly necessary but as I couldn't understand what this code does I wanted to ensure that the functionality is the same. 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-harden...@vger.kernel.org Signed-off-by: Justin Stitt <justinst...@google.com> --- Changes in v2: - included refactor of another strncpy in same file - Link to v1: https://lore.kernel.org/r/20230913-strncpy-drivers-edac-edac_mc_sysfs-c-v1-1-d232891b0...@google.com --- Note: build-tested only. --- drivers/edac/edac_mc_sysfs.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c index 15f63452a9be..ce025a20288c 100644 --- a/drivers/edac/edac_mc_sysfs.c +++ b/drivers/edac/edac_mc_sysfs.c @@ -229,8 +229,7 @@ static ssize_t channel_dimm_label_store(struct device *dev, if (copy_count == 0 || copy_count >= sizeof(rank->dimm->label)) return -EINVAL; - strncpy(rank->dimm->label, data, copy_count); - rank->dimm->label[copy_count] = '\0'; + strscpy_pad(rank->dimm->label, data, copy_count); return count; } @@ -535,7 +534,7 @@ static ssize_t dimmdev_label_store(struct device *dev, if (copy_count == 0 || copy_count >= sizeof(dimm->label)) return -EINVAL; - strncpy(dimm->label, data, copy_count); + strscpy_pad(dimm->label, data, copy_count); dimm->label[copy_count] = '\0'; return count; --- base-commit: 2dde18cd1d8fac735875f2e4987f11817cc0bc2c change-id: 20230913-strncpy-drivers-edac-edac_mc_sysfs-c-e619b00124a3 Best regards, -- Justin Stitt <justinst...@google.com>
