Nexus 7 OS Marshmallow downgrade to Lollipop for Nethunter Install Advice for Newbie.

[EmperorNeo]

Attention all Nethunter gurus Seriously, i just got a new ASUS Nexus 7 2013 with Marshmallow 6.0 build MRA58K on it. Here is my status, i'm new to Android and to Linux for that matter. I've been studying the CEH exam (classes, books etc.) I have BackTrack & Kali Linux on my Laptop and it's going very well. I'm not a total novice but i'm treading in new waters here so i'm asking for some guidance. That being said...I know i have to downgrade my OS to Lollipop as it's the version that Nethunter requires. My question: Is there any advice you pro's can give me as i begin this? Are there any videos or threads that would be useful for me? I DO NOT want to destroy my machine. Lastly i'm wondering once i have Nethunter installed and working on my Nexus will i still be able to use the apps and basic tablet features or will Nethunter consume the tablet making it a complete Linux machine? Thanks in advance to anyone brave enough to walk with me on this.

-Neo

[stinkybit]

Hi,

first of all, when nethunter is installed, you can use your tablet like any other Android tablet. Nethunter basically is a custom kernel, a couple of apps and a kali chroot environment.
The easiest way to downgrade would be the nethunter windows installer - that would be (almost) just a next-next-finish procedure.

If you would like to use your kali installation, you should "apt-get install google-nexus-tools" and download the right factory image from
https://developers.google.com/android/nexus/images and follow the instructions given there (you should use the command "nexus-adb" instead of "adb" - rename it in the install-all-script mentioned at 6. as well - or use an alias, link or something and you can skip "fastboot oem lock").

Having a clean Lollipop installation, you might want to go on here:
http://web.archive.org/web/201509071...r.com/prepare/
http://web.archive.org/web/201509071...r.com/install/

I think, there is something new coming soon, but the steps mentioned above should work for now.

[xNotta]

What is the exact factory image that we should be using for Lollipop NetHunter? 5.1.1 (LMY48T)?

[stinkybit]

What is the exact factory image that we should be using for Lollipop NetHunter? 5.1.1 (LMY48T)?

Yes, LMY48T ist the latest and works fine for me.

[xNotta]

Yes, LMY48T it the latest and works fine for me.

Thank you for the reply.
When I used LMY48T the Kali Installer did not replace/patch the kernel, it remained the google kernel so nothing worked.

Am I going too far off topic asking why the kernel didn't get changed in my installs of LMY48T and how to fix it?

[stinkybit]

You are right, I haven't had a look at the kernel.
Don't know, why this didn't work, maybe we should swicht back to LMY48M (I had this running with NH before)

Edit: That didn't work either. I'm sure, I had this version installed before.
Either I didn't have a look at the kernel as well, or it worked better because I used the windows Installer and OTG updates before.

[xNotta]

You are right, I haven't had a look at the kernel.
Don't know, why this didn't work, maybe we should swicht back to LMY48M (I had this running with NH before)

Edit: That didn't work either. I'm sure, I had this version installed before.
Either I didn't have a look at the kernel as well, or it worked better because I used the windows Installer and OTG updates before.

Is it possible for someone to just compile us a flashable kernel or post a working zImage that we can use instead of relying on the NH flashable zip installer?

I was playing around with Marshmellow and found out that SELinux is locked to Enforcing which prevents SuperSU from being installed and a modified boot.img fixed it.
Maybe we need a modified boot.img with SELinux set to Permissive to allow the NH flashable .zip to modify the stock kernel?
Link to the Marshmellow modified boot.img from Chainfire on XDA: http://forum.xda-developers.com/apps...ellow-t3219344 (I can confirm that the modified boot.img was required for supersu to install the binaries to /system, without it nothing wrote to /system)

[stinkybit]

I think, you're right about the boot.img. I Downloaded the Windows-Installer on my corporate laptop and reinstalled android/NH:
It Downloads Version LMY47V and a boot image named "modified_boot_razor_5.1.1_LMY47V.img" (there is one with the same name on androidfilehost.com - not sure, if its the same image. "modified_boot_razor_5.1.1_LMY48T.img" is available, too, but didn't work for me, maybe I did something wrong during the installation...).

So after taking a backup with TWRP following the process of the installer:
- I stopped after the factory reset and did another factory reset within android, so my 32GB are fully shown (there is a bug, showing only ~12GB, if you don't).
- Updated all the way to LMY48T via OTA updates.
- Went back to the installer to install boot.img, Nethunter, TWRP, ... and root the device.
- Downloaded the latest nethunter.zip and installed via TWRP
- Restored Data with TWRP.

So, this way took quite some time, was pretty lame and a pain in the @$$ and most of the work has been done twice, but I'm back to the latest Lollipop version with a working Kali kernel and fine off with that (and since it might kill some time during my business trip next week, I won't touch it before).
Maybe someone with a better understanding of Android can derive a better way to go (or a way with linux)...

Is the installation order of boot.img and TWRP important? Maybe that was the problem, modified_boot_razor_5.1.1_LMY47V.img didn't change a thing before.

[xNotta]

Found a tool to change SELinux from Enforcing to Permissive.
Unfortunately it's been removed from the Play Store, but it available on XDA and on FDroid:
SELinuxModeChanger (XDA)
F-Droid
github

[Blacksite]

Was this ever resolved for EmperorNeo? I bought this Nexus and had the same issue - it came with And. 6.0 updated on it and solved it handily. You may be using some other method or something I am missing, but in the interest of being helpful wugfresh freeware, a quick visit to the Google drivers page for 5.1.1, flashed back to unrooted stock 5.1.1, then flashed the nethunter .zip file I saved the to the device on to the 5.1.1 by using TWRP TWRP and wala. You will want to play with SuperSu to get everything working correctly permissions wise, but besides that I've had no issues. Also, I used the ####X as opposed to the one above, as the one I'm using is actually the oldest version of the 5.1.1. version. It was a total guess - but sometimes newer is not better and I did not have the patience at that time to fight with it. YMMV.

[clone]

downgrading back to 5.1 from 6.1 is not the solution I expected. build MMB29K should be the current target build for the n7 2013 device.

;[