`strncpy` is deprecated for use on NUL-terminated destination strings [1].
We should prefer more robust and less ambiguous string interfaces.
We expect name to be NUL-terminated based on its numerous uses with
functions that expect NUL-terminated strings.
For example in i2c-core-base.c +1533:
| dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name);
NUL-padding is not required as `adap` is already zero-alloacted with:
| adap = devm_kzalloc(&usbif->dev, sizeof(struct i2c_adapter), GFP_KERNEL);
With the above in mind, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html
Link: https://github.com/KSPP/linux/issues/90
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
if (!adap)
return -ENOMEM;
- strncpy(adap->name, usbdev->serial, sizeof(adap->name) - 1);
+ strscpy(adap->name, usbdev->serial, sizeof(adap->name));
adap->owner = THIS_MODULE;
adap->dev.parent = &usbif->dev;
adap->dev.of_node = usbif->dev.of_node;