FS#3745 - Wireless 'isolate' option not working in brcmfmac driver

[openwrt-bot]

GeoffN:

Device: BCM4356 WiFi chip + brcmfmac
OpenWRT Version: 21.02 (commit 50f2f25 [4 days ago])

I experienced the problem using OpenWrt 21.02 on a device using the brcmfmac driver for the BCM4356 chip.

I've only been able to test this on an InvizBox 2 (not supported by OpenWRT) but I suspect it to also be a problem for other devices using brcmfmac.

Steps to reproduce:

On a device running OpenWRT 21.02 and with a WiFi chip using the brcmfmac driver:

Set wireless..isolate='1' on the WiFi interface that uses the brcmfmac driver.

Devices connected to the WiFi interface should be isolated from each other, but are not.

Notes / Potential fixes:

I was able to fix this issue by building with a specific patch for brcmfmac from the latest Cypress Linux WiFi Driver Release (FMAC)(https://community.cypress.com/t5/Wi-Fi-Bluetooth-for-Linux/Cypress-Linux-WiFi-Driver-Release-FMAC-2021-01-14/m-p/268899). The particular patch that fixed the issue can be found in the .zip file linked in the latest Cypress driver release. cypress-fmac-v5.4.18-2021_0114.zip > cypress-patch-v5.4.18-2021_0114.tar.gz > cypress-patch > 0004-brcmfmac-support-AP-isolation.patch.

The patch has not been accepted into linux-wireless yet. But there are details about it here: https://patchwork.kernel.org/project/linux-wireless/patch/20200901063237.15549-2-wright.feng@cypress.com/.

Let me know if you need any more information or there's anything I can do to help sort this out. Thanks.