Linux and all UNIX-like operating systems come with necessary access permissions for each object. Having different access permissions play a key role in security, so no one person has access to a level of permissions that they do not need and thus exposing them to additional security vulnerabilities. Typically one who does not need access to something often doesn’t know how to use it and thus the security issue arises. There is also the fact that closing the door on being able to access particular files means that nothing can ever go wrong and thus the security is naturally greater in those instances.

There are three levels of permissions available for each object: read, write and modify. Depending on the permissions associated with the user account you are logged into will depend on what you can do with your level of permissions. The root user account (that is the account you are using when you get root access on Android) has access to all three objects (read, write and modify) and thus has full administrative control over the operating system.

SM-P355

The Android operating system that is installed on the Samsung Galaxy Tab A SM-P355 tablet is based on the same Linux kernel as the Linux operating systems that are used for desktop computers and thus are subject to the same permissions and user accounts. You don’t hear about the root user account being there because it is taken away by Android developers by default whereas if you use Linux on a computer the root user account is typically offered when you first set up the computer (for most Linux distributions). However, when you get root access on the devices that run on the Android operating system, it is getting in control of the root user account so you can have full read, write and modifying permissions. That kind of control over Android means you can start installing any of the apps that need access to any of those three areas whereas before you couldn’t just install any apps. You could only install and run the apps that did not require the root permission.

Details We Should Know

  • Chainfire had the MMB29M.P355XXU1BPG2 firmware build number running on the Samsung Galaxy Tab A SM-P355 tablet when he developed the version of the rooting file found in this guide. You don’t need that same version running on your tablet because him telling you the firmware he had running is not necessarily suggesting you need to be running on the same. He gives the firmware information so you can use it as an indicator.
  • If you find that your device does not boot up correctly after flashing the rooting file in the guide below you need to leave a message on the CF-Auto-Root tool thread on XDA-Developers that contains the recovery image file from the firmware you are running so Chainfire can use it to update the rooting file so that it starts working again.
  • You need to have the Samsung Galaxy Tab A tablet that comes with the SM-P355 model number to use this guide. Any of the other model numbers will not work, and you risk bricking them by flashing the wrong file.
  • You need a computer that is running on the Windows operating system. It doesn’t matter which version of Windows as long as it is above Windows XP.

Files We Need

  • Download the CF-Auto-Root tool for the Samsung Galaxy Tab A SM-P355 tablet running on the Android 6.0.1 Marshmallow software updates.
  • Download the Samsung USB Drivers for the Windows operating system that is running on the computer.

Rooting the Samsung Galaxy Tab A SM-P355 tablet running on the Android 6.0.1 Marshmallow software updates by flashing the CF-Auto-Root tool

  1. Start off by logging into the Windows computer using the admin account, so you are using the Odin flashing tool with the administrative permissions. (Alternatively, you can sometimes right-click on the Odin file and choose to run it as the administrator if you cannot log into the admin account on the computer because you don’t have the account details).
  2. Unlock the Developer Options menu on the Samsung Galaxy Tab A SM-P355 tablet so you can use the options that are available to developers.
  3. Enable the USB Debugging Mode on the Samsung Galaxy Tab A SM-P355 tablet so you can make the necessary changes to the Android software that is running on the device for the rooting to work.
  4. Install the Samsung USB Drivers on the computer so the Odin flashing tool can identify the type of device you are connecting to the computer with the USB cable otherwise the rooting cannot work.
  5. Open the Downloads folder that is available on the Windows computer and then extract the rooting file to the Downloads folder.
  6. Pick up the Samsung Galaxy Tab A SM-P355 tablet and boot it into the Download Mode that is available and then connect it to the computer with its USB cable.
  7. Click on the Odin flashing application from the Downloads folder and then check that Odin shows an added message and a color coming from the ID: COM port so you know that the Samsung USB Drivers are working and the device is ready for the flashing.
  8. Do not make any changes to the default settings that the Odin flashing tool offers from the Odin Options tab.
  9. Click on the AP button and then browse to the Downloads folder where the rooting file was extracted and click on the MD5 rooting file so that it is uploaded to the Odin flashing tool.
  10. Click on the Start button from the Odin flashing application and then read all of the writing that rolls down the display of the tablet so you know what is happening next.
  11. Wait until you get a message stating that the tablet is going to reboot in ten seconds and then check the Odin flashing tool user interface for a message stating that it has passed which is available inside a new green box.

That is everything you need to do in order to root Samsung Galaxy Tab A SM-P355 tablets running on the Android 6.0.1 Marshmallow software updates by flashing the systemless root version of the CF-Auto-Root tool by Chainfire. The systemless root version of the tool means that you have extra chances to keep root access after updating and taking a factory reset will fully unroot now from the Recovery Mode on the device. Apart from that, there is no difference other than the what the rooting tool goes about giving you the root access. None of that is important for the results though which is you being able to install all of the same root applications that you could before when you had root access to an earlier version for the same CF-Auto-Root tool.