ppp cmmand port listens on ipv6 only if kernel has

[Julian Stacey]

Hackers, (cc Brian at a. who's maybe expert, from examples seen in share :-)
I'm not clear if this is a bug or a config error:
        It seems though my /usr/sbin/ppp was moving traffic
        to & from internet, it was only listening for commands
        (not data) on ipv6, not ipv4, thus I could not type commands
        like dial & drop, unless instead of running ppp -auto 
        instead I invoked ppp manually in foreground on localhost.

Detail:
I have 2 alternate firewall/ gateways connected to world via DSL.
Each ran 4.10-Release OK. I raised one to 6.1-Release.
With a 6.1 Release custom kernel compiled with
        options         INET6
& /etc/ppp/ppp.conf with
        set server +12345 mypasswd
sockstat -l     showed only:
 USER     COMMAND    PID   FD PROTO  LOCAL ADDRESS         FOREIGN ADDRESS
 root     ppp        1020  9  tcp6   *:12345               *:*
(& no 2nd line for ipv4), & so from my internal host, this failed:
        pppctl -p mypasswd dsl:12345
& in fact even on my host named dsl, this failed
        telnet localhost 12345
So I built a new kernel without INET6 & then sockstat -l showed
 root     ppp        972   9  tcp4   *:12345               *:*
& that works OK, I can finally manually control my PPP link up & down via
        pppctl -p mypasswd dsl:12345
On my 4.10 host which has a kernel with both
        options      INET
        options      INET6
(as also has 4.10 GENERIC), that has always worked OK, &  sockstat -l   shows
 root     ppp        512    9 tcp46  *:21389               *:*
& pppctl -p mypasswd dsl:12345          works OK.

Questions:
- Did I misconfigure something ?
- Does ppp on 6.1 perhaps not now listen on ipv4 if INET6 is in kernel ?
  (Unfortunate if so, as INET6 in in GENERIC kernel)
- Should ppp have an extra flag added, forcing "Do listen on ipv4" ?
- Is this a bug ? Should I file a send-pr ?  Did I misconfig something ?

Julian
--
Julian Stacey.  BSD Unix C Net Consultancy, Munich/Muenchen  http://berklix.com
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