[Q] Set warranty bit -> dd to hide text ?

[raz3k]

Hello all,

I thought of a possibility to remove the "Set warranty bit : %s". I allmost did it but not having the possibility and knowledge of recovering from a brick i stumbled and thought to ask you guys before i do something stupid. I remember i did a similar thing to HTC Sensation to the hboot bootloader by changing the **** UNLOCKED *** text to something i liked but i'm not sure if additional checks are being made on GT-I9195 LTE.

I searched with grep inside /dev/block/mmcblk0 and found the string "Set Warranty Bit : %s". Dumping the first 10 Mb will include the area where the text is.

Will the phone brick if i dd if=/dev/block/mmcblk0 of=/mnt/extSdcard/binary.bin, transfer it on the pc, hexedit the text and variable replacing every letter with 0x20 and flashing it back on the phone will mess up the GPT(checksum maybe?) and brick the phone or should i give it a go ?


Thanks.

 

[Mortitheon]

*text*.

Make a backup and give it a go.

 

[raz3k]

Hi,

Thanks for the response, what kind of backup should i do because if GPT checksum fails i don't think i'll be able to unbrick without JTAG.

After some research i found that this text is in the aboot partition which is /dev/block/mmcblk0p5 - 2097152 bytes in size.

Will i brick it or not ? Does the aboot partition have a checksum on itself done by other chianloader ?
For example does TriangleAway from chainfire modify this partition?

Cheers!

 

[aguaz]

After some research i found that this text is in the aboot partition which is /dev/block/mmcblk0p5 - 2097152 bytes in size.

Will i brick it or not ? Does the aboot partition have a checksum on itself done by other chianloader ?

I'm of no help but I'd be interested in that as well.
aboot is the Knox boot loader (the master of all boot related partitions?)
Here @SilviuMik wrote some info about Knox and partitions: http://forum.xda-developers.com/showpost.php?p=48607142&postcount=19

 

[raz3k]

2698

I'm of no help but I'd be interested in that as well.
aboot is the Knox boot loader (the master of all boot related partitions?)
Here @SilviuMik wrote some info about Knox and partitions: http://forum.xda-developers.com/showpost.php?p=48607142&postcount=19

Thanks for your info, i will dig even more, on the other side my image is set up, i just need a confirmation from a guru so that i can flash without keeping my fingers crossed.

 

[Miccia]

If u could do this u could remove knox, i think that u can brick ur phone. Jtag ready, but wait for a guru

 

[raz3k]

In the meantime i've spoken with @SilviuMik and he has not played with a knox enabled aboot.img because he doesn't have a knox enabled phone but in his opinion it will brick.

After digging even more i found @babuk123 's post here that is in fact a solution to debrick in case of a hard brick that could result in after fiddling around with aboot.img .

Technically what you need to do is dump partitions from p0 -> p7 from a working phone ( or even better your phone while it still works ) and dd them on a sdcard. They state that the qualcomm chip will read stuff from the sdcard if the internal memory is bricked, but i can't be sure (i'm not sure if the chip priorities the sdcard in spite of the internal memory if known binary code is found on the sdcard).

Can someone confirm that they unbricked their S4 mini using this method ? Because if i can debrick i will give it a go.

L.E. : I tried a different approach, i made a backup of p0 -> p7, wrote it on the sdcard, modified it to suppress the warranty void string, booted and the phone ignored it completely which means that either this method does not work at all or it may work if the eMMC is corrupted. For now i'm stuck again.


Thanks.

 

[aguaz]

Maybe @E:V:A can shed some light on how the boot chain actually works (sbl1-3,aboot,rpm,tz) and how to boot off an sdcard.
He has written some interesting Qualcomm stuff http://forum.xda-developers.com/showthread.php?t=1856327

See also http://forum.xda-developers.com/showthread.php?t=1769411

 

[xdevilium]

Bump.

Don't do anything stupid, but don't give up!