[FS#750] 802.11r Fast Transition Not working

[LEDE Bugs]

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

User who did this - mjaustin2 (mjaustin2) 

Attached to Project - LEDE Project
Summary - 802.11r Fast Transition Not working
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Medium
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - Device: WRT1900ACSv2
Version: LEDE 17.0 - 17.01.1, and trunk

I was able to get 802.11r working on an older TP Link TL-WR1043ND v1.1 using the configuration below, however, when I use the same configuration on my WRT1900ACSv2, devices either refuse to associate, or ones that do associate, do so without FT-PSK.

Devices that attempt to use FT-PSK do not return the MDIE in their Associate Frame. I have tried to compile a hostapd without the debugging messages stripped, but no additional errors were provided by hostapd. I have looked at packet captures from the TL-WR1043ND that do work and I cannot see anything different with the probe responses or beacon frames between the two devices types that would immediately indicate an issue. Admittedly, I'm no expert with 802.11 protocols, so I'm seeking some help here. I've hit a wall. I can provide example frame captures and device configurations as needed.

My example configuration looks like the following:

config wifi-device 'radio0'
	option type 'mac80211'
	option hwmode '11a'
	option path 'soc/soc:pcie-controller/pci0000:00/0000:00:01.0/0000:01:00.0'
	option htmode 'VHT80'
	option channel '149'
	option country 'US'
	option log_level '0'

config wifi-iface 'roaming_test'
	option device 'radio0'
	option network 'lan'
	option mode 'ap'
	option ssid 'RoamIO'
	option encryption 'psk2+ccmp'
	option key 'somewpa2sharedkey'
	option ieee80211r '1'
	option pmk_r1_push '1'
	option mobility_domain 'beef'
	option nasid 'ap0wlan0'
	option r1_key_holder 'deadbeefcafe'
	option macaddr 'de:ad:be:ef:ca:fe'
	list r0kh 'de:ad:be:ef:ca:fe,ap0wlan0,000102030405060708090a0b0c0d0e0f'
	list r0kh 'de:ad:be:ef:4d:ad,ap1wlan0,000102030405060708090a0b0c0d0e0f'
	list r1kh 'de:ad:be:ef:ca:fe,de:ad:be:ef:ca:fe,000102030405060708090a0b0c0d0e0f'
	list r1kh 'de:ad:be:ef:4d:ad,de:ad:be:ef:4d:ad,000102030405060708090a0b0c0d0e0f'


More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=750