[FS#769] Firewall stops traffic / DHCP to WAN interface.

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Lars Jensen (ledj) 

Attached to Project - LEDE Project
Summary - Firewall stops traffic / DHCP to WAN interface.
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Medium
Priority - Very Low
Reported Version - lede-17.01
Due in Version - Undecided
Due Date - Undecided
Details -  - WRT1900ACS v2
 - LEDE Reboot 17.01.1 r3316-7eb58cf109 / LuCI lede-17.01 branch (git-17.100.70571-29fabe2)
 - Happens periodically (restart firewall solves problem immediately)
   
>From log:

conntrack: generic helper won't handle protocol 47. Please consider loading the specific helper module.

Restarting firewall resolves the issue, and WAN gets DHCP address instant.

I don't know if it happens when a new DHCP lease from my internet service provider on the WAN interface is occurring OR if connection tracking is failing and firewall blocks traffic totally OR some other thing happens :-)

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=769