[Android Q&A, Help & Troubleshooting] Delgoth:
Hello! I’ve come, because in my quest to root my recent Galaxy S Devices, I’ve hit a big fork in the road and I don’t have the knowledge base to answer the last few questions I have. I feel like I should know the answers here, but for some reason I am lost to what to do next. I don’t quite understand how the newer root methods work these days, since working with the system & recovery images isn’t as easy with the newer Samsungs.

I got together with a developer, [MENTION=7945178]droidvoider[/MENTION], where together we came up with this idea to get a root shell capable of at least remounting the filesystem R/W before reboot. He coded it on 6.0.1, and I talked a whole lot while I tested it on 5.1.1.

The Greyhat Root Console post#63

I'll start with the fact that I do not have Cellular Service. I no longer own a Note 5 N920A. But I do still own an S5 G900V, S6 Edge G925V, and a S7 Edge G935V. They serve as Wi-Fi Only Devices, and they are owned by myself. So slightly selfishly, I concern myself only with modifications that allow the device to boot, working network services are not a primary concern of mine. As they can more than likely be configured after boot by someone smarter than me.

I know that normally DM-Verity, KNOX, Encryption, U/G IDs, and SELinux, play a big role in allowing a user to execute processes as the root user. I am running 5.1.1 Android on my S6e & 7.0 on my S7e. I have an Engineering Kernel and boots normally with ADB Root Shell access. I have an Engineering Sboot, and allows me a non Root ADB Shell while booted normally in Stock Recovery. Right now the Eng Kernel I have, sets SELinux to Enforcing Mode. If I use the stock factory binary kernel, I lose root adb shell access but gain Permissive SELinux Mode. How do I inject root from here in a stable fashion?

Using "DD" on Android 6.0.1 post#18

Page 4 for File and GHR Console

Page 5 further discussion of Console

Page 6 GHR Console

I'm going to go into some detail here about the Firmware I've been flashing just so everyone knows without having to ask. I'm almost really hoping maybe we could all muster one more attempt at rooting this Note 5 variant.

I really feel like I really might have something here, especially with the updated binaries of "Farm Root", "CVE 2016-5195 (dirtycow)", and bootimgtools (mkbootimg & unpackbootimg). All compiled for arm64-v8a. Thanks to [MENTION=7945178]droidvoider[/MENTION] for helping to compile those. I'm not a linux Expert by any means, but I'm on a mission, and I do know a few things. With all of the Security Bulletins that have come out since November, there should be plenty of Attack Vectors for using the LL Eng Kernel or DirtyCow to gain enough Kernel Privileges to maybe even unlock the dang bootloader. Or maybe bypass the signature check for one boot. LL-based UCU1AOGG Recovery Mode does not use DM-Verity when exiting, and the Combination Firmware doesn't seem to use it at all So....

Q1.) Can someone please help me get at least a systemless root installed? WITHOUT using a custom recovery?

It might need to actually be a system root though looking at the Galaxy S8.

This should be possible using the LL Engineering Kernel & Engineering Sboot for the Factory Binary. Especially since the August builds are fully exploitable by DirtyCow, and with an eng Kernel that is half the battle we were using dirtycow for in the first place. Now we should be able to use DirtyCow to finish the root injection. Because the Factory Binary does not utilize DM-Verity that is obvious. So using the Factory Combination Firmware, there may actually be a way to legit boot a custom recovery I feel, even if only for one boot, that is plenty enough if prepared when that oneshot boot happens. Once installed with the full Combination Bootloader (ODIN BL file) I can then flash any N920A LL ODIN AP File. All the way back to N920AUCU1AOGG. Warranty Bit Intact, Official Status, Normal Rebooting. In fact, after everything I've done thus far, I have still yet to trip my KNOX Warranty (Still 0x00).

**************

** MM 6.0.1 **

**************

Here are the contents of the tar.md5's:

tar -tvf AP_N920AUCS3BPH4_CL7563702_QB10603229_REV00_user_low_ship.tar.md5
-rw-rw-r-- dpi/dpi 28746016 2016-08-10 00:31 boot.img
-rw-rw-r-- dpi/dpi 29413664 2016-08-10 00:32 recovery.img
-rw-rw-r-- dpi/dpi 4125403456 2016-08-10 00:33 system.img
-rw-r--r-- dpi/dpi 549536816 2016-08-10 00:33 userdata.img

tar -tvf BL_N920AUCS3BPH4_CL7563702_QB10603229_REV00_user_low_ship.tar.md5
-rw-rw-r-- dpi/dpi 1634576 2016-08-10 00:31 sboot.bin
-rw-rw-r-- dpi/dpi 1095680 2016-08-10 00:28 param.bin
-rw-rw-r-- dpi/dpi 2113808 2016-08-10 00:28 cm.bin

tar -tvf CP_N920AUCS3BPH4_CL7563702_QB10603229_REV00_user_low_ship.tar.md5
-rw-rw-r-- dpi/dpi 37269840 2016-08-10 00:28 modem.bin

tar -tvf CSC_ATT_N920AATT3BPH4_CL7563702_QB10603229_REV00_user_low_ship.tar.md5
-rw-rw-r-- dpi/dpi 3072 2016-08-10 00:32 NOBLELTE_USA_ATT.pit
-rw-r--r-- dpi/dpi 89608656 2016-08-10 00:34 cache.img

For this MM Stock Firmware, I've also come across this Modem for a Z3X Flash Box, that is used when direct unlocking this device. I do know, that when I have this CP installed, I do have access to the APN Editor, to Add/Modify/Delete APN's:

tar -tvf N920A_UCS3BPH4_CP_FOR_UNLOCK.tar
-rw-r--r-- 0/0 37269840 2016-08-10 00:28 modem.bin

******

**************

** LL 5.1.1 **

**************

I’ve happened upon the full ODIN flash-able SW Rev 3 Factory Binary for the AT&T Galaxy Note 5. It allowed me to do a full firmware downgrade from MM 6.0.1 to LL 5.1.1 without worrying about trying to downgrade my binary counter in download mode. It’s the only 5.1.1 build I’ve seen that isn’t a binary 2-(SW REV 2) & It contains these files:

Filename: COMBINATION_FA51_N920AUCU3APH1_CL6053901_QB10608083_REV00_user_mid_noship.tar.md5

tar -tvf COMBINATION_FA51_N920AUCU3APH1_CL6053901_QB10608083_REV00_user_mid_noship.tar.md5
-rw-rw-r-- dpi/dpi 1634576 2016-08-10 06:44 sboot.bin
-rw-rw-r-- dpi/dpi 1095680 2016-08-10 06:43 param.bin
-rw-rw-r-- dpi/dpi 2113808 2016-08-10 06:43 cm.bin
-rw-rw-r-- dpi/dpi 24660256 2016-08-10 06:44 boot.img
-rw-rw-r-- dpi/dpi 24754464 2016-08-10 06:44 recovery.img
-rw-r--r-- dpi/dpi 1537858544 2016-08-10 06:44 system.img
-rw-r--r-- dpi/dpi 4292768 2016-08-10 06:44 persdata.img
-rw-rw-r-- dpi/dpi 36163408 2016-08-10 06:43 modem.bin
-rw-rw-r-- dpi/dpi 3072 2016-08-10 06:44 NOBLELTE_USA_ATT.pit

Using ODIN v3.12.5, I flashed this firmware using the AP slot overtop of the Full 3BPH4, and after flashing the Factory Binary these are the build details that boot up with zero errors. Mind you, I have tried this with, and without, a sim card inserted. It is not lost on me either, that UCS3BPH4 (Stock) and UCU3APH1 (Factory) have the same build dates listed on them.

***

* Device := SM-N920A

* Android Version := 5.1.1

* Baseband Version := N920AUCU3APH1

* Kernel Version := 3.10.61 August 10th 2016

* Build Number := LMY47X.FA51_N920AUCU3APH1

* SELinux Status := Permissive

***

From [MENTION=5254272]TechNyne66[/MENTION] I got the LL Eng Kernel from the 2APB2 build. I have yet to see any other UCE branded files.

tar -tvf N920AUCE2APB2.tar
-rwxr-xr-x 0/0 27326752 2016-02-11 01:42 boot.img

But flashing this kernel into the Factory Binary sets SELinux to Enforcing, which makes things a bit more difficult. And I don't know how to edit the Kernel in a way I can repack it for flashing. My attempts thus far have failed when trying to flash a repacked boot.img. Probably because I did not make the necessary build.prop tweaks, and because I didn't use the correct compression levels to repack. What I mentioned earlier about not understanding the filesystem all that well anymore, stems from not having a broad understanding of build/default.prop & the various .rc/init files.

This is also possibly due to Samsung using a customized header for the Kernel's Binary.

Q2.) Is there a way to update the UID/GID from 'dpi/dpi' to '0/0' without modifying the signature embedded into the tar.md5?

Q3.) Is there a way to extract the extra data from the end of the file?

Q4.) Can I examine the persdata.img directly, to see it's contents before flashing?

I don't know how to view the img format and how to extract it.

My post is too long, so I'm moving to post #2