I needed adbd to always run as root in order to push/pull files, but I wanted to stick as close as possible to stock, so I just modified the production boot.img with a patched version of adbd that enforces it to always run as root. I used a boot.img for Android 4.4.2 extracted from the factory images  provided by Google.
I thought that it could be usefull to somebody else so... here you have.
It comes in two flavors:
CWM installable .zip 
boot.img for fastboot[/URL] 
 Google Factory Images : https://developers.google.com/androi...=es#hammerhead
 CWM Installable .zip : https://mega.co.nz/#!lJVxWCaA!QA4Zo0...QCuIzuYFN bnFU
 boot.img : https://mega.co.nz/#!sYE0xDZL!PpR1Gz...Sdsee4mGF d5PA
[KERNEL][STOCK][4.4.2] Only Adb Insecure, a Kernel for the Google Nexus 5
Kernel Special Features: Stock kernel, but with adbd running always as root, so you can adb push/pull/remount/shell/etc as root
Last Updated 2014-01-16