kerberos 5 login (krb 5.1.2-5)

[Jerry Heyman]

In article <tslvg7evwi6.fsf at konishi-polis.mit.edu>,
 hartmans at mit.edu (Sam Hartman) writes:
>I'd step through login in a debugger and see where it hangs.  If you
>cannot do that, then start inserting debugging print statements and
>binary search where it hangs.

Not a hang - an infinite loop, hence the CPU utilization.  I've
got it narrowed down to the code section:

in src/util/pty/update_utmp.c, in function best_utxent():

    /*
     * Uh-oh, someone didn't enter our pid.  Try valiantly to search
     * by terminal line.
     */
    i = 0;
    best = -1;
    PTY_SETUTXENT();
    while ((utxp = PTY_GETUTXLINE(search)) != NULL) {
        if (better(search, utxp, &utxtmp)) {
            utxtmp = *utxp;
            best = i; }
        memset(utxp, 0, sizeof(*utxp));
        i++;
    }

The ttyname that I'm running on is:  /dev/ttyAE/AAEy
but that is getting mangled to: kAEyttyAE/AAEy

Is there a problem in the pty_update_utmp() function around line
554 (my numbers are off because of inserted printf()s).  It seems
that there is a strncpy () call without appending a NULL character.

#ifdef __hpux
    strcpy(utmp_id, cp);
#else
    if (len > 2 && *(cp - 1) != '/')
      sprintf(utmp_id, "k%s", cp - 1);
    else
      sprintf(utmp_id, "k0%s", cp);
#endif
    strncpy(utx.ut_id, utmp_id, sizeof(utx.ut_id));