Posts Tagged ‘Android 4.2’

Nexus 7: Insecure Boot Image for Android

Monday, November 26th, 2012

Basically I just wanted to have my Titanium Backup working again after the OTA-Update…
This insecure boot image was created from factory image nakasi-jop40c-factory-6aabb391.tgz;
build number JOP40C (that’s codename “grouper”).

It requires a) the “Google Nexus 7 ADB Interface” to be installed,
b) that /tools and /platform-tools are defined within the $PATH
and c) that the device’s boot-loader is already OEM unlocked.

First, open a terminal or MS-DOS prompt and boot into the bootloader menu:

adb reboot bootloader

To download the image-file and boot it once (it’s rather not recommend to flash it):

fastboot boot boot-insecure-jop40c-nakasi.img
downloading 'boot.img'...
OKAY [  0.656s]
OKAY [  0.016s]
finished. total time: 0.672s

The device should boot until the X (or swirling dots) are displayed, no further.

Next, to remount the system partition read/write:

adb shell mount -o rw,remount -t ext4 /dev/block/platform/sdhci-tegra.3/by-name/APP /system

To install su & busybox (after further updates it’s ordinary enough to push/chmod su only):

adb push su /system/bin
adb push SuperSU_0.98.apk /system/app/
adb push busybox /system/xbin/
adb shell chmod 06755 /system/bin/su
adb shell chmod 0644 /system/app/SuperSU_0.98.apk
adb shell chmod 04755 /system/xbin/busybox

And finally, just reboot.

adb shell reboot

Since Android 5.1 Lollipop has SE Linux enabled …it’s probably easier to:
a) upload to SD card and b) boot into recovery, by entering:

fastboot boot recovery-clockwork-

and c) select “Update from SD” and then choose the – done.

Related Downloads:
ADB Interface