I find on xda a temporary fix for this issue (thanks buraktamturk) http://forum.xda-developers.com/show...postcount=3041
I simply done a shell script that give you and install the default gateway ip for your active data connection.
So every time you active a new data connection and you must done a tethering Wifi/USB condivision,
remember to run before this script.
Whats you need for make it work.
Your device must be rooted and you must have busybox installated link: https://play.google.com/store/apps/d....busybox&hl=en
Install Root Explorer from play store (is not free) https://play.google.com/store/apps/d...explorer&hl=en
You need it for execute wifi-tethering-lpv-fix.sh (you can also use terminal emulator even if you need more steps)
Download and Unzip the script attached and save it on your Nexus5 folder (i.e. /system) and give permission rwx (read-write-execute) with root explorer apk. (or chmod 777 wifi-tethering-lpv-fix.sh with terminal emulator)
RUN WIFI/USB TETHERING SCRIPT
After that every time you start a new data connection done this steps:
1. Run wifi-tethering-lpv-fix.sh with Root exlorer apk
2. Enable and disable tethering ; After that re-enable it. (this step is important otherwise dhcp server is not started - internal bug from Android L preview)
Now your USB or WIFI tethering connection would be work.