Uggg!!! I can’t imagine using Android Marshmallow without a root access. For people like myself, who enjoy root access on Android, Nexus provide the cynosure way to maintain root without having to start mokeying around.
Android Marshmallow OS has started rolling out to some devices and there is a Beta version of SuperSU and a modified image to root your Android 6.0 Marshmallow.
To root a device running Android Marshmallow, like LG Nexus 5X and Huawei Nexus 6P, you will have to flash a modified boot.img file on it which contains the kernels and modified ramdisk, which enables you to gain root from SElinux set to enforcing mode.
If your device is Nexus 6 or Nexus 9, this might force your device to factory reset itself. If that happens, all you need to do is install TWRP and sideload the new version of SuperSU.
It should be possible to root Android Marshmallow without a modified boot but because of the increment in security measure in Android this day, makes it more tedious to root Marshmallow without a modified boot but Chainfire is on the look out on how to root Marshmallow without a modified image.
Finally, it should be noted that when you root Android even Marshmallow, you won’t be able to receive any update via OTA but factory image will still work in that case.
Would you like to root Android 6.0 marshmallow without a modified image?