static void __maybe_unused timersubspec(struct timespec *a, const struct timespec *b)
{
	a->tv_sec -= b->tv_sec;
	a->tv_nsec -= b->tv_nsec;
	if (a->tv_nsec < 0) {
		a->tv_nsec += 1000000000;
		a->tv_sec--;
	}
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.