chkrootkit (part #3)

In chkrootkit
    

     if (!quiet)
    {
      signal(SIGALRM, read_status);
      alarm(5);
    }

...


 void read_status() {
   double remaining_time;
   static long last_total_bytes_read=0;
   int diff;

    diff = total_wtmp_bytes_read-last_total_bytes_read;
   if (diff == 0) diff = 1;
   remaining_time=(wtmp_file_size-total_wtmp_bytes_read)*5/(diff);
   last_total_bytes_read=total_wtmp_bytes_read;

    printf("Remaining time: %6.2f seconds\n", remaining_time);
/*
   signal(SIGALRM,read_status);

    alarm(5);
*/
}

I'll just quote the man page for signal()

DESCRIPTION
       The behavior of signal() varies across UNIX versions, and has also var‐
       ied historically across different versions of Linux.   Avoid  its  use:
       use sigaction(2) instead.  See Portability below.

Is it a security bug? Unlikely. Is it a bug? Maybe. Should it be fixed? Yes, if you want to maintain it..

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