I have not been following the discussion in this thread since I don't have access to the device anymore. The whole OpenWrt flashing process I followed is described in the first posts.
I don't know if your command will work. 10 days ago, user Double-G kindly wrote this:
Guys, I got openwrt install and work properly (without SPI flashing) using OnperWRTInvasion by @acecilia to gain root access; and flash snapshots version of mir3g-v2-squashfs-sysupgrade.bin using @rogerpueyo method found here. after auto reboot, openwrt.
thank you , please make a youtube video Tutorial how you flash openwrt on mi4a gigabit edition ,special thanks to all ppl made this happen great news.
That's super good news, @hey07!
Could you tell us what was the stock firmware version you performed OpenWRTInvasion successfully on? 2.28.132? Was it the one that came with the device, or did you download it from somewhere else?
I'll be adding it to the ToH in the wiki (or, please, feel free to do it).
it is the latest stock 2.28.132. just run OpenWRTInvasion on it directly.
It is easy. or you can follow my summary below. Please thanks @acecilia for his root access script. and flash command by @rogerpueyo
gain root using OpenWRTInvasion (mine running stock 2.28.132)
you can follow his guide (very clear) or
-download OpenWRTInvasion here
-install requirement (I use pi4 raspbian, python ready)
-open terminal and run "python3 remote_command_execution_vulnerability.py"
-put your mir4a ip
-put your mir4a stok (can be found in your router web url, just type router ip your browser)
the script will upload exploit to your router now you can access using telnet with login "root" without password
Flash openwrt (i used snapshots version of mir3g-v2)
-telnet using your router ip
-login with "root"
-cd /tmp/
-wget http://downloads.openwrt.org/snapshots/targets/ramips/mt7621/openwrt-ramips-mt7621-xiaomi_mir3g-v2-squashfs-sysupgrade.bin
(it will download bin file to router tmp folder (wget not recognize https))
-mtd -e OS1 -r write openwrt-ramips-mt7621-xiaomi_mir3g-v2-squashfs-sysupgrade.bin OS1
It will say:
Unlocking OS1 ...
Erasing OS1 ...
Writing from openwrt-ramips-mt7621-xiaomi_mir3g-v2-squashfs-sysupgrade.bin to OS1 ...
Rebooting ...
-Done (it will reboot and come back with openwrt)
thank you i flashed openwrt after reboot i can't access router gui what should i do ?
edit :i can confirm it works on my router with firmware 2.28.132
but when i connect to 2.4G WIFI it show me no internet connection !!
edit:after flash it again 2.4 ghz wifi works
Hello does anyone have to share original firmware 4th gigabit global ROM: 2.28.132. PLEASE PLEASE.
Not that I know, firmware has not been released
you can dump your firmware using a ch341a programmer but i didnt backup my original firmware and running openwrt now i dont need stock firmware anymore i'm enjoying openwrt thanks to @acecilia
I got a bunch of dumps right here, because I flashed 20+ devices this way. So it should be no problem, to send you one of them.
But the problem could be, that the mac-address of your device would change to that one in the dump.
Also I don´t know, if there is some kind of device-specific calibration data in the dump of if calibration processes are done while booting the device (I think I read something about calibration in the console while the device was booting...).
Can you upload a dump somewhere please? 
or even better, two or three dumps, so we can compare them and check what you are saying about the mac address.
Of course - any suggestions for a hoster to choose?
MEGA
media fire
Ok ... just used that one... I think it should not matter 
https://anonfile.com/n8P8Tajfo2/R4AG_R4A_spi-flsh_dumps_zip
It includes 10 dumps, as I said I got some more if you need them. (Could not access them right now.)
I can run the exploit on firmware 2.28.26 (sorry it is 2.28.62)
after flash openwrt, wifi not activated,
connect lan port, ssh to machine, opkg install luci and done.
Firmware 2.28.26 is the only one officially released by Xiaomi, right? The one that is in Chinese?
EDIT: also I see in your log that the version you are running is 2.28.62, not 2.28.26.
thank you mirror link to your file:
http://www.mediafire.com/file/ueyz7zd7q6ys1ex/R4AG%26R4A_spi-flsh_dumps.zip/file
I am realising now that the exploit may be useful to install OpenWrt in other Xiaomi routers and firmware versions
yes yes yes and Y E S !!!!!
Thanks @acecilia and your team
Question: Is there any newer/stable version that we can use ?
