cpu_util(double pcpu[3])
{
    static struct timeval last;
    static clock_t clast;
    static struct rusage rlast;
    struct timeval temp;
    clock_t ctemp;
    struct rusage rtemp;
    double timediff;
    double userdiff;
    double systemdiff;

    if (pcpu == NULL) {
        gettimeofday(&last, NULL);
        clast = clock();
	getrusage(RUSAGE_SELF, &rlast);
        return;
    }

    gettimeofday(&temp, NULL);
    ctemp = clock();
    getrusage(RUSAGE_SELF, &rtemp);

    timediff = ((temp.tv_sec * 1000000.0 + temp.tv_usec) -
                (last.tv_sec * 1000000.0 + last.tv_usec));
    userdiff = ((rtemp.ru_utime.tv_sec * 1000000.0 + rtemp.ru_utime.tv_usec) -
                (rlast.ru_utime.tv_sec * 1000000.0 + rlast.ru_utime.tv_usec));
    systemdiff = ((rtemp.ru_stime.tv_sec * 1000000.0 + rtemp.ru_stime.tv_usec) -
                  (rlast.ru_stime.tv_sec * 1000000.0 + rlast.ru_stime.tv_usec));

    pcpu[0] = (((ctemp - clast) * 1000000.0 / CLOCKS_PER_SEC) / timediff) * 100;
    pcpu[1] = (userdiff / timediff) * 100;
    pcpu[2] = (systemdiff / timediff) * 100;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.