not firebird, but I know why. Selinux is set to permissive. I'm just gonna get a modified version of the kernel which I made. Sets selinux to enforcing and will fix your problem.
https://drive.google.com/file/d/0B4ICBlRA1gm8QnV5VUI4MmFjZHc/view?usp=sharing
To flash go into twrp, choose install...