IndexError: list index out of range

[dragonxtek]

I have the following network:

mininet> net
h0 h0-eth0:s0-eth1
h1 h1-eth0:s7-eth1
s0 lo:  s0-eth1:h0-eth0 s0-eth2:s1-eth1 s0-eth3:s3-eth1 s0-eth4:s5-eth1
s1 lo:  s1-eth1:s0-eth2 s1-eth2:s2-eth1
s2 lo:  s2-eth1:s1-eth2 s2-eth2:s7-eth2
s3 lo:  s3-eth1:s0-eth3 s3-eth2:s4-eth1
s4 lo:  s4-eth1:s3-eth2 s4-eth2:s7-eth3
s5 lo:  s5-eth1:s0-eth4 s5-eth2:s6-eth1
s6 lo:  s6-eth1:s5-eth2 s6-eth2:s7-eth4
s7 lo:  s7-eth1:h1-eth0 s7-eth2:s2-eth2 s7-eth3:s4-eth2 s7-eth4:s6-eth2
controller

When I run it, Hedera shows me the following error:

IPV4 processing
[PATH]10.0.0.1<-->10.0.0.2: [7]
shortest_forwarding: Exception occurred during handler processing. Backtrace from offending handler [_packet_in_handler] servicing event [EventOFPPacketIn] follows.
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/ryu/base/app_manager.py", line 290, in _event_loop
    handler(ev)
  File "/home/ryu/ryu/app/Hedera/Hedera.py", line 96, in _packet_in_handler
    self.shortest_forwarding(msg, eth_type, ip_pkt.src, ip_pkt.dst)
  File "/home/ryu/ryu/app/Hedera/Hedera.py", line 398, in shortest_forwarding
    path, flow_info, msg.buffer_id, msg.data)
  File "/home/ryu/ryu/app/Hedera/Hedera.py", line 325, in install_flow
    port_pair = self.get_port_pair_from_link(link_to_port, path[0], path[1])
IndexError: list index out of range

Is a Hedera issue? Do you have a topology example to test it?
I'm running ryu-manager 4.12