mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-01-19 05:22:06 -05:00
e100c01efa
strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. We expect ae->value_string to be NUL-terminated because there's a comment that says as much; these attr strings are also used with other string APIs, further cementing the fact. Now, the question of whether or not to NUL-pad the destination buffer: lpfc_fdmi_rprt_defer() initializes vports (all zero-initialized), then we call lpfc_fdmi_cmd() with each vport and a mask. Then, inside of lpfc_fdmi_cmd() we check each bit in the mask to invoke the proper callback. Importantly, the zero-initialized vport is passed in as the "attr" parameter. Seeing this: | struct lpfc_fdmi_attr_string *ae = attr; ... we can tell that ae->value_string is entirely zero-initialized. Due to this, NUL-padding is _not_ required as it would be redundant. Considering the above, a suitable replacement is strscpy() [2]. 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 <justinstitt@google.com> Link: https://lore.kernel.org/r/20240226-strncpy-drivers-scsi-lpfc-lpfc_ct-c-v2-1-2df2e46569b9@google.com Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>