`strncpy` is deprecated for use on NUL-terminated destination strings [1].
A suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on its destination buffer argument which is _not_ the case for `strncpy`!
It was pretty difficult, in this case, to try and figure out whether or not the destination buffer was zero-initialized. If it is and this behavior is relied on then perhaps `strscpy_pad` is the preferred option here.
Kees was able to help me out and identify the following code snippet which seems to show that the destination buffer is zero-initialized.
| skl = devm_kzalloc(&pci->dev, sizeof(*skl), GFP_KERNEL);
With this information, I opted for `strscpy` since padding is seemingly not required.
Also within this patch is a change to an instance of `x > y - 1` to `x >= y` which tends to be more robust and readable. Consider, for instance, if `y` was somehow `INT_MIN`.
[1]: www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [2]: manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html
Link: https://github.com/KSPP/linux/issues/90 Suggested-by: Kees Cook keescook@chromium.org Signed-off-by: Justin Stitt justinstitt@google.com --- sound/soc/intel/skylake/skl-topology.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/soc/intel/skylake/skl-topology.c b/sound/soc/intel/skylake/skl-topology.c index 96cfebded072..67f08ec3a2ea 100644 --- a/sound/soc/intel/skylake/skl-topology.c +++ b/sound/soc/intel/skylake/skl-topology.c @@ -3154,12 +3154,12 @@ static int skl_tplg_fill_str_mfest_tkn(struct device *dev,
switch (str_elem->token) { case SKL_TKN_STR_LIB_NAME: - if (ref_count > skl->lib_count - 1) { + if (ref_count >= skl->lib_count) { ref_count = 0; return -EINVAL; }
- strncpy(skl->lib_info[ref_count].name, + strscpy(skl->lib_info[ref_count].name, str_elem->string, ARRAY_SIZE(skl->lib_info[ref_count].name)); ref_count++;
--- base-commit: 0b4a9fdc9317440a71d4d4c264a5650bf4a90f3c change-id: 20230726-asoc-intel-skylake-remove-deprecated-strncpy-9dbcfc26040c
Best regards,