I have an android phone and an android tablet. Both not rooted. I want to use adb as host on the tablet and as client on the phone, using an USB-OTG adapter.

I downloaded connectbot as terminal emulator on the tablet. I also downloaded the ARM binary for adb onto the tablet. However I'm getting the following error when I try to execute the binary:

user@tablet:/storage/sdcard0/download $ ./adb-arm-binary.bin devices
/system/bin/sh: ./adb-arm-binary.bin: can't execute: Permission denied

Is there anyway to get ADB as a host to run on an android 4.4.2 tablet without root?

OR: Is there any way to root said tablet without a PC?

The whole reason I need this is because I need to access dumpsys logs from the phone but I do not have a PC or laptop. A way to get dumpsys logs directly on the phone without root would suffice too, but AFAIK dumpsys is impossible to access for non-system application.