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[SOLVED] Completely format system data cache partitions[making all zeroes]

I know the obvious ans would be to use 4ext superwipe.
What I want is like re-writing those partitions with all memory locations set to zeroes. The 4ext full wipe only works like quick format in windows desktop.
Any ideas how to do it?
____________________
Solved. See post 17 for details.

pushpann said:
I know the obvious ans would be to use 4ext superwipe.
What I want is like re-writing those partitions with all memory locations set to zeroes. The 4ext full wipe only works like quick format in windows desktop.
Any ideas how to do it?
Click to expand...
Click to collapse
Had to search a bit, but found an article that explains how to do this. It links to 3 apps (havn't tested myself, just remember there's no going back), from the description the first one only works on SD card, the second one might (it does not mention which partitions it formats), and the last one seems to be removed.
I did not read the whole article, but I suggest you do that before doing anything.
Good luck.

pushpann said:
I know the obvious ans would be to use 4ext superwipe.
What I want is like re-writing those partitions with all memory locations set to zeroes. The 4ext full wipe only works like quick format in windows desktop.
Any ideas how to do it?
Click to expand...
Click to collapse
Hi,
A RUU will reset everything back to stock, and fix any partition issues.
Is that what you are after?

malybru said:
Hi,
A RUU will reset everything back to stock, and fix any partition issues.
Is that what you are after?
Click to expand...
Click to collapse
As he said, he wants it to be completely formatted, meaning no data can be recovered, which is like a hard full wipe - no way to restore.
RUU does format the data partition, but it only removes records of files, and the data itself is still available and possible to read (until new files will be written over it).

No! I dont want to get involved with RUU stuff.. I just want to completely wipe my phone.. Like complete formatting of the USB drives. All system and data partitions set to zeroes.
In simple words, if you do quick formating on pendrives, you can restore (some or all data before format, depends on what you've put on the drive after format ) using some Data Recovery tools.
What i believe is that recovery just wipes the memory addresses, without putting zeroes on all the memory locations. have been googling for this for almost a week, haven't got any clue yet!

pushpann said:
I know the obvious ans would be to use 4ext superwipe.
What I want is like re-writing those partitions with all memory locations set to zeroes. The 4ext full wipe only works like quick format in windows desktop.
Any ideas how to do it?
Click to expand...
Click to collapse
I would do it this way (this is something I came up with, and if it screws up anything, you are responsible) :
Write a script that reformat your nand rom and then dumps (creates) a huge file containing zeroes. Then reformat using 4ext and repartition.
I am curious, why exactly do you want to do this? The lack of results from Google would suggest that this is not something people would normally do.
JAM THAT THANKS BUTTON.
Happy to help.

I assume you're not going to use the phone after?
If you aren't going to use the phone after, one word. Sledgehammer.
If you are keeping the phone; create a file on the partition filled with rubbish (linux has a command for this). Make sure it fills the entire partition and then run mkfs.ext4 /dev/block/partition. Repeat a dozen times or create a script to do it for you.
It's easier than erasing the whole NAND disk and partitioning it. Mainly because you'll wipe the recovery partition and create an expensive paperweight. Which brings me back to sledgehammer.
Sent from my HTC

pushpann said:
No! I dont want to get involved with RUU stuff.. I just want to completely wipe my phone.. Like complete formatting of the USB drives. All system and data partitions set to zeroes.
In simple words, if you do quick formating on pendrives, you can restore (some or all data before format, depends on what you've put on the drive after format ) using some Data Recovery tools.
What i believe is that recovery just wipes the memory addresses, without putting zeroes on all the memory locations. have been googling for this for almost a week, haven't got any clue yet!
Click to expand...
Click to collapse
On my first commented I linked to an article which gives two ways to wipe your phone (set to zeroes and all). Here are the two apps:
https://play.google.com/store/apps/details?id=com.kovit.p.forevergone
https://play.google.com/store/apps/details?id=ch.ethz.infsyssec.sddroid
Try those to see if they format the Data partition.

Far_SighT said:
I would do it this way (this is something I came up with, and if it screws up anything, you are responsible) :
Write a script that reformat your nand rom and then dumps (creates) a huge file containing zeroes. Then reformat using 4ext and repartition.
I am curious, why exactly do you want to do this? The lack of results from Google would suggest that this is not something people would normally do.
JAM THAT THANKS BUTTON.
Happy to help.
Click to expand...
Click to collapse
Hmm.. My phone has become very laggy.. No matter what ROM flash, what firmware I flash.
DennisBold said:
I assume you're not going to use the phone after?
If you aren't going to use the phone after, one word. Sledgehammer.
If you are keeping the phone; create a file on the partition filled with rubbish (linux has a command for this). Make sure it fills the entire partition and then run mkfs.ext4 /dev/block/partition. Repeat a dozen times or create a script to do it for you.
It's easier than erasing the whole NAND disk and partitioning it. Mainly because you'll wipe the recovery partition and create an expensive paperweight. Which brings me back to sledgehammer.
Sent from my HTC
Click to expand...
Click to collapse
By hearing what you say, i kinda feel little scared to do these steps. Anyway thanks for the suggestion..
astar26 said:
On my first commented I linked to an article which gives two ways to wipe your phone (set to zeroes and all). Here are the two apps:
https://play.google.com/store/apps/details?id=com.kovit.p.forevergone
https://play.google.com/store/apps/details?id=ch.ethz.infsyssec.sddroid
Try those to see if they format the Data partition.
Click to expand...
Click to collapse
Those apps dont work.. By internal data they mean internal sdcard not system or data partition.
BTW just saw this app called lagfix. It says it will discard the unused blocks, but doesnot work on my phone.. Has anyone tried it? For me it's saying trim on system,data and cache not supported! DAMN

DennisBold said:
I assume you're not going to use the phone after?
If you aren't going to use the phone after, one word. Sledgehammer.
If you are keeping the phone; create a file on the partition filled with rubbish (linux has a command for this). Make sure it fills the entire partition and then run mkfs.ext4 /dev/block/partition. Repeat a dozen times or create a script to do it for you.
It's easier than erasing the whole NAND disk and partitioning it. Mainly because you'll wipe the recovery partition and create an expensive paperweight. Which brings me back to sledgehammer.
Sent from my HTC
Click to expand...
Click to collapse
Yeah, I had similar thoughts. I was going for repartition becasue then the whole of nandroid can be wiped in one go.
To clean the phone, sledgehammer / mowing the device with a car (or both, one after the other) are the best methods.
Here's one more idea. Create a pseudo nandroid backup with all of your nandroid partitions(/system /data /cache etc) filled with garbage/zeroes. Then restore that. And bam, the nandroid is hard formatted (after a quick format of course).
Like always, it's your phone. I am not responsible for anything that you do to it.
JAM THAT THANKS BUTTON.
Happy to Help.

pushpann said:
Hmm.. My phone has become very laggy.. No matter what ROM flash, what firmware I flash.
By hearing what you say, i kinda feel little scared to do these steps. Anyway thanks for the suggestion..
Those apps dont work.. By internal data they mean internal sdcard not system or data partition.
BTW just saw this app called lagfix. It says it will discard the unused blocks, but doesnot work on my phone.. Has anyone tried it? For me it's saying trim on system,data and cache not supported! DAMN
Click to expand...
Click to collapse
Tried it yesterday, it's meant for certain devices that did not use the TRIM command like they should (Many Nexus 7 tablets were slowed down by this issue), but it seems the Sensation does not need it (or at least our kernels do not support the command).
What seems as the only way to do so is to create many blank files and delete them (like many already said). you can create a large file and copy it a few times to the Data partition, which will fill it, and then delete it. using a normal file manager will work (or you can use "adb push" command to push the file a couple of times).

Far_SighT said:
Yeah, I had similar thoughts. I was going for repartition becasue then the whole of nandroid can be wiped in one go.
To clean the phone, sledgehammer / mowing the device with a car (or both, one after the other) are the best methods.
Here's one more idea. Create a pseudo nandroid backup with all of your nandroid partitions(/system /data /cache etc) filled with garbage/zeroes. Then restore that. And bam, the nandroid is hard formatted (after a quick format of course).
Like always, it's your phone. I am not responsible for anything that you do to it.
JAM THAT THANKS BUTTON.
Happy to Help.
Click to expand...
Click to collapse
You sure it does complete format while restoring nandroid? BTW i still am not sure how to fill system and data partitions with zeroes or garbage! Anyway thanks for the heads up

pushpann said:
You sure it does complete format while restoring nandroid? BTW i still am not sure how to fill system and data partitions with zeroes or garbage! Anyway thanks for the heads up
Click to expand...
Click to collapse
You shouldn't have to worry about formatting empty space. No one ever, except possibly computer forensics is going to want information from an empty phone. They have access to browsing history from Google, call records from your mobile provider and ban access details from your banks. They wouldn't need your phone. There are things that make it hard for the average person. Including mounting the NAND disk in a way that it can be opened like a normal disk drive, and then running the tools to restore data. If someone really wanted data it's possible but they will not go through all that for 500MB of bank details, porn or whatever people do with phones these days. If you're trying to hinder the police because you did something wrong, then you should just stop.
Theoretically it can be done through an android device but cross compiling tools to recover data is long and tedious to do. There is nothing so important that someone would spend hours creating tools for an Android device to restore data that may already be irrevocably gone. Not to mention the learning curve for new software. If you are worried, burn the device and buy something new. That is the general rule for sensitive data. Make sure it's gone before you move on.
It's safe to click "Format all partitions" and then erase your SD card and give your phone away.
If it helps, install Android on top. Choose something big. Most of your application data is stored on your SDCard FYI.
Lastly, if it's lag you are trying to fix. Go backwards with Android not forwards. JellyBean demands more than ICS and ICS demands more than GingerBread. Having the latest OS doesn't work for everyone. For example, Windows 8.1 doesn't work for me because there's no fastboot support without huge editing of system drivers. The same is true in Android. GingerBread stability may be more important than ICS or JB features, or JellyBean features may be more important. However don't expect lag free 4.2 or 4.3, our devices may work with it, but they were never intended to go above 4.1(Ville C2 updates stop there too I think) due to hardware limitations. Others may argue differently, but you should question the effort they're (including me) putting in with kernel and device tree upgrades. It's amazing work nonetheless but it basically shouldn't have to be done if the device were supported. Buy a new device if you want the latest and greatest. My Sensation has become a trophy for me to the amazing things you can do with one of HTCs first dual core phones. I don't expect it to work without some kinks and bugs or even fatal flaws but I still respect it for having running Sense 3.0 to 5.0 (yes I've tried it).
Sorry for the rant. I'm a little bit grumpy, but hope it helps explains why you can mostly erase and install a new version of android then throw the device away and be relatively safe.
There's probably going to be someone who reads all of this and thinks I'm crazy, to that guy or girl. Thanks for reading all of it!
Sent from my HTC

DennisBold said:
You shouldn't have to worry about formatting empty space. No one ever, except possibly computer forensics is going to want information from an empty phone. They have access to browsing history from Google, call records from your mobile provider and ban access details from your banks. They wouldn't need your phone. There are things that make it hard for the average person. Including mounting the NAND disk in a way that it can be opened like a normal disk drive, and then running the tools to restore data. If someone really wanted data it's possible but they will not go through all that for 500MB of bank details, porn or whatever people do with phones these days. If you're trying to hinder the police because you did something wrong, then you should just stop.
Theoretically it can be done through an android device but cross compiling tools to recover data is long and tedious to do. There is nothing so important that someone would spend hours creating tools for an Android device to restore data that may already be irrevocably gone. Not to mention the learning curve for new software. If you are worried, burn the device and buy something new. That is the general rule for sensitive data. Make sure it's gone before you move on.
It's safe to click "Format all partitions" and then erase your SD card and give your phone away.
If it helps, install Android on top. Choose something big. Most of your application data is stored on your SDCard FYI.
Lastly, if it's lag you are trying to fix. Go backwards with Android not forwards. JellyBean demands more than ICS and ICS demands more than GingerBread. Having the latest OS doesn't work for everyone. For example, Windows 8.1 doesn't work for me because there's no fastboot support without huge editing of system drivers. The same is true in Android. GingerBread stability may be more important than ICS or JB features, or JellyBean features may be more important. However don't expect lag free 4.2 or 4.3, our devices may work with it, but they were never intended to go above 4.1(Ville C2 updates stop there too I think) due to hardware limitations. Others may argue differently, but you should question the effort they're (including me) putting in with kernel and device tree upgrades. It's amazing work nonetheless but it basically shouldn't have to be done if the device were supported. Buy a new device if you want the latest and greatest. My Sensation has become a trophy for me to the amazing things you can do with one of HTCs first dual core phones. I don't expect it to work without some kinks and bugs or even fatal flaws but I still respect it for having running Sense 3.0 to 5.0 (yes I've tried it).
Sorry for the rant. I'm a little bit grumpy, but hope it helps explains why you can mostly erase and install a new version of android then throw the device away and be relatively safe.
There's probably going to be someone who reads all of this and thinks I'm crazy, to that guy or girl. Thanks for reading all of it!
Sent from my HTC
Click to expand...
Click to collapse
I dont wanna sell my phone and I know that my data isnt that valueable that anyone will try to read my data with hard efforts. My sensation used to perform awesome 2-3 months back, and now that I must have quick formatted my system and data partitions more than 1500 times, i think a full wipe may do some help for those nag n lag issues.
And about going back to GB? Man, Everyone feels GB is sad after using ICS/JB. If my phone doesnot stop lagging every second after I format these partitions, i think its time for a new phone!
Anyway thanks for such a detailed reply

pushpann said:
I dont wanna sell my phone and I know that my data isnt that valueable that anyone will try to read my data with hard efforts. My sensation used to perform awesome 2-3 months back, and now that I must have quick formatted my system and data partitions more than 1500 times, i think a full wipe may do some help for those nag n lag issues.
And about going back to GB? Man, Everyone feels GB is sad after using ICS/JB. If my phone doesnot stop lagging every second after I format these partitions, i think its time for a new phone!
Anyway thanks for such a detailed reply
Click to expand...
Click to collapse
The lag isn't from formatting. You can try ARHD ICS if you want. Or probably Sense 4+ with 4.1.2 but anything above that might not work out great.
Sent from my HTC

pushpann said:
I dont wanna sell my phone and I know that my data isnt that valueable that anyone will try to read my data with hard efforts. My sensation used to perform awesome 2-3 months back, and now that I must have quick formatted my system and data partitions more than 1500 times, i think a full wipe may do some help for those nag n lag issues.
And about going back to GB? Man, Everyone feels GB is sad after using ICS/JB. If my phone doesnot stop lagging every second after I format these partitions, i think its time for a new phone!
Anyway thanks for such a detailed reply
Click to expand...
Click to collapse
How old is your Sensation? I could well be that your nand is dying. In that case, repartition your phone and make /system and /data from parts seldom used (like /cache).
If you want data security, full encryption will keep noobs away.

Thanks for the replies guys!
Today i actually did the zeroing of the partitions with Nandroid method.. I download an app called dummy file creator and it created dummy files(files with zeroes all over it. after searching in internet it seemed legit method of fully zeroing out the memory locations) in data partition untill it ran out of memory. Then i copied those files to system partition too manually till it also became full(I had to do this manually because the app didnt support creating dummy files in system partition) and made nandroid of data and system separately then did almost a dozen time 4ext format and restoring the nandroid. Finally i formatted all the partitions and installed Codename Lungo ROM(CM10.1).
HELL YEAH! it feels FASTer. Not sure if its gonna last long.

pushpann said:
Thanks for the replies guys!
Today i actually did the zeroing of the partitions with Nandroid method.. I download an app called dummy file creator and it created dummy files(files with zeroes all over it. after searching in internet it seemed legit method of fully zeroing out the memory locations) in data partition untill it ran out of memory. Then i copied those files to system partition too manually till it also became full(I had to do this manually because the app didnt support creating dummy files in system partition) and made nandroid of data and system separately then did almost a dozen time 4ext format and restoring the nandroid. Finally i formatted all the partitions and installed Codename Lungo ROM(CM10.1).
HELL YEAH! it feels FASTer. Not sure if its gonna last long.
Click to expand...
Click to collapse
Just found something and wanted to add - for future reference - Android Tuner seems to be able to make the TRIM operation on all partitions on our sensation, in a much easier way.

pushpann said:
Thanks for the replies guys!
Today i actually did the zeroing of the partitions with Nandroid method.. I download an app called dummy file creator and it created dummy files(files with zeroes all over it. after searching in internet it seemed legit method of fully zeroing out the memory locations) in data partition untill it ran out of memory. Then i copied those files to system partition too manually till it also became full(I had to do this manually because the app didnt support creating dummy files in system partition) and made nandroid of data and system separately then did almost a dozen time 4ext format and restoring the nandroid. Finally i formatted all the partitions and installed Codename Lungo ROM(CM10.1).
HELL YEAH! it feels FASTer. Not sure if its gonna last long.
Click to expand...
Click to collapse
Can you guide me? i want to do that but i'm noob . how did you do that? pls help me

BSHD666 said:
Can you guide me? i want to do that but i'm noob . how did you do that? pls help me
Click to expand...
Click to collapse
hehe you found it:good:

[Q] HOXL Data Recovery

Hi fellow xda-members,
I recently wiped my One XL 32GB with the HBOOT Factory Reset,
didnt know that it wipes the internal storage aswell...
Needless to say that I work with the phone and the data is priceless...
I already tried to pipe the whole mmcblk0 via netcat, which worked fine.
All but the FAT 25GB partition are getting recognised via testdisk.
Did 2 dd's, so I got 2 raw-images of mmcblk0 and mmcblk0p36.
None of the recovery tools (Recuva, testdisk, @active, pc inspector recovery, etc.) did find any files.
The Partition wasnt formatted and also wasnt mounted yet, there should be no changes made from android since the wipe.
If I open the mmcblk0p36 via hex editor, its complete null.
The mmcblk0 image has random data all over the whole area,
but also mostly null (estimated 80-90% null). The internal memory was almost full,
about 22/25GB, so there are 3 options:
1.:The HBOOT Factory Reset doesnt delete just the FAT, but also nulls the whole data. (Which would be weird, because the reset took 3-5 seconds, I doubt it can null 25gigs in 5 seconds ;D)
2.:The chip has a kind of "fast-wipe" option, which makes it possible to null 25gb in 5 seconds, never seen this before, but who knows
3.:The data wasnt nulled, but dd doesnt read 1:1, which would be also weird.
Is there any app/commandline tool for android to directly check
whats on the specific part of the internal storage?
Or are there ways to access the memory directly to get
a exact image of the internal storage for recovery other than "dd if=/dev/block/mmcblk0"?
If none of the above, is there a chip-recovery expert that can recover the files with jtag/advanced hardware?
Thanks for all replys
criestr

Was the phone modified? If so, the factory reset in the bootloader doesn't just wipe the data, but it completely corrupts it, that's probably why you're getting no data show up with the recovery tools you're using.
Sent from my Evita

timmaaa said:
Was the phone modified? If so, the factory reset in the bootloader doesn't just wipe the data, but it completely corrupts it, that's probably why you're getting no data show up with the recovery tools you're using.
Sent from my Evita
Click to expand...
Click to collapse
Yes, the phone is rooted and s-off'ed,
I personally didnt change the partition alignment,
but updated the hboot from somewhat 1.09 to 2.18 a few days before.
Has the layout been changed in the past?
And, if the data was really corrupted, what to do about?
Is there any chance to recover the files?
thanks
criestr

criestr said:
Yes, the phone is rooted and s-off'ed,
I personally didnt change the partition alignment,
but updated the hboot from somewhat 1.09 to 2.18 a few days before.
Has the layout been changed in the past?
And, if the data was really corrupted, what to do about?
Is there any chance to recover the files?
thanks
criestr
Click to expand...
Click to collapse
I don't see how the partition alignment is relevant, but no I don't believe it's changed. I don't think you're going to have much luck in recovering your data, if all those recovery tools aren't yielding any positive results.

timmaaa said:
I don't see how the partition alignment is relevant, but no I don't believe it's changed. I don't think you're going to have much luck in recovering your data, if all those recovery tools aren't yielding any positive results.
Click to expand...
Click to collapse
If the partition alignment has changed, the hboot factory reset could possibly null more/less/other/the wrong ranges of memory while wiping.
I have new results:
I've checked the fresh raw dumps with a hex editor, finding out the range of mmcblk0p36, the internal sdcard only contains nulls.
Thats why every recovery tool doesnt gather any file.
I know that dd copys every bit 1:1, so I am out of luck with dd.
Does someone have experience with jtag raw data recovery?
Is there a way to gather other/deeper data with jtag?
Thanks
criestr

What would happpen if i zero-filled the entire storage?

I'm new to rooting and installing new roms on android systems, but i work making custom linux and windows systems and optimizing for over a decade.
So, my optimizing spirit is tingling to try everything, but this particular thing is just a question, i'm not intending to actually do it.
When using the terminal on TWRP, i've noted that i could fdisk the internal storage (/dev/mmcblk0) and that i could see all the partitions it had, like system, data, cache and so on.
TWRP and other tools only re-format those partitions with ext4 in order to wipe, so i used 'dd' in terminal to zerofill the ones i knew i could wipe and then formatted then in ext4 (with 'dd if=/dev/zero of=partition').
But i had a bigger question and i couldn't find answer nowhere: What would happen if i actually used dd to zero fill EVERYTHING, the entire /dev/mmcblk0, including the very partition table, every byte on it?
Would the device still enter fastboot mode? Would i still be able to connect it on the fastboot utility and flash a new recovery or do something?
Or, if after zero filling, still on the terminal, if i used fdisk to re-create the proper partitions and then formatted them, could i reboot, re-flash the recovery (once there would be the partition for it) and do an very-deep-clean install?
Not that i think that this has any utility, i just wonder if this would end up rendering the device totally useless, or if the fastboot mode is stored in an ROM chip, like a computer bios is.

Guilherme Franco said:
I'm new to rooting and installing new roms on android systems, but i work making custom linux and windows systems and optimizing for over a decade.
So, my optimizing spirit is tingling to try everything, but this particular thing is just a question, i'm not intending to actually do it.
When using the terminal on TWRP, i've noted that i could fdisk the internal storage (/dev/mmcblk0) and that i could see all the partitions it had, like system, data, cache and so on.
TWRP and other tools only re-format those partitions with ext4 in order to wipe, so i used 'dd' in terminal to zerofill the ones i knew i could wipe and then formatted then in ext4 (with 'dd if=/dev/zero of=partition').
But i had a bigger question and i couldn't find answer nowhere: What would happen if i actually used dd to zero fill EVERYTHING, the entire /dev/mmcblk0, including the very partition table, every byte on it?
Would the device still enter fastboot mode? Would i still be able to connect it on the fastboot utility and flash a new recovery or do something?
Or, if after zero filling, still on the terminal, if i used fdisk to re-create the proper partitions and then formatted them, could i reboot, re-flash the recovery (once there would be the partition for it) and do an very-deep-clean install?
Not that i think that this has any utility, i just wonder if this would end up rendering the device totally useless, or if the fastboot mode is stored in an ROM chip, like a computer bios is.
Click to expand...
Click to collapse
The hardware side of fastboot is typically stored on mmcblk0 somewhere in bootloader, meaning it is in the boot partition which is one of the things you would wipe. This would hardbrick your device, rendering it virtually unrecoverable, with a very slim chance of recovering, if its even possible at all, typically, it isn't possible.
Just stick with the tools already designed to handle any wiping that you need.
Sent from my SCH-I535 using Tapatalk

Droidriven said:
The hardware side of fastboot is typically stored on mmcblk0 somewhere in bootloader, meaning it is in the boot partition which is one of the things you would wipe. This would hardbrick your device, rendering it virtually unrecoverable, with a very slim chance of recovering, if its even possible at all, typically, it isn't possible.
Just stick with the tools already designed to handle any wiping that you need.
Sent from my SCH-I535 using Tapatalk
Click to expand...
Click to collapse
That's interesting, i thought my fear was irrational, but it seems to be the case.
But, why is it like that? Why leave everything you need in an RW memory, while you could use a piece of ROM memory to grant the basic functions and the capability of manipulating the RW one (like a PC BIOS)?
In computers you usually don't need to mind wiping everything you can, your device will still work or will be at least recoverable.
Even screwing BIOS and firmwares in computers and some other devices is something that usually won't render the device unrecoverable. Although they sure can cause a hell lot of headache and may need physical intervention like soldering chips and such, i myself strove to find the correct bios images for certain motherboards and to flash the chips because i didn't have an proper flashing equipment, so i had to build an arduino circuit for that (but i luckily worked with detachable chips).
The only other device i know to be rendered unrecoverable are hard drives if you wipe the firmware stored in platter, as it has the service area, which keeps a big part of all information needed to properly address and read the disk and even the other system tracks spread through the disk, that are also needed to control the head, to read and to correct data errors.
Some of these are written at factory, but others must be writable so the hard drive can take care of itself.
But you'd only be able to mess with these data with proprietary low-level software using specific microcode, zero fill and low-level formatting software can't write on any of these tracks, they can only access LBA addressed tracks.

Guilherme Franco said:
That's interesting, i thought my fear was irrational, but it seems to be the case.
But, why is it like that? Why leave everything you need in an RW memory, while you could use a piece of ROM memory to grant the basic functions and the capability of manipulating the RW one (like a PC BIOS)?
In computers you usually don't need to mind wiping everything you can, your device will still work or will be at least recoverable.
Even screwing BIOS and firmwares in computers and some other devices is something that usually won't render the device unrecoverable. Although they sure can cause a hell lot of headache and may need physical intervention like soldering chips and such, i myself strove to find the correct bios images for certain motherboards and to flash the chips because i didn't have an proper flashing equipment, so i had to build an arduino circuit for that (but i luckily worked with detachable chips).
The only other device i know to be rendered unrecoverable are hard drives if you wipe the firmware stored in platter, as it has the service area, which keeps a big part of all information needed to properly address and read the disk and even the other system tracks spread through the disk, that are also needed to control the head, to read and to correct data errors.
Some of these are written at factory, but others must be writable so the hard drive can take care of itself.
But you'd only be able to mess with these data with proprietary low-level software using specific microcode, zero fill and low-level formatting software can't write on any of these tracks, they can only access LBA addressed tracks.
Click to expand...
Click to collapse
The simple answer would be that the manufacturers don't want you messing with the device to begin with so they don't do anything to make flashing or recovering easier for us.
Sent from my SCH-I535 using Tapatalk

Galaxy On5 Data Recovery

Hi.
I mistakenly flashed my Android Galaxy On5 (using Odin's "AP" option) with one of the Exynos files. I saw something about "userdata" and knew immediately I had made a mistake, even though I did not load anything in the Odin "userdata" option. Why I did this probably isn't relevant, but I'm happy to provide more detail.
My question, however, is a simple one: Having done this, is it still possible to recover the user data that is no longer visible on the phone? When I reboot the phone without TWRP, it looks like it has been factory reset.
The phone is rooted, and I can see the device shares with "df". I can't see any secondary SD card based on the information I found about it sitting on top of where the SIM card is installed. I have done plenty of computer data recoveries from hard disk.. But every tool I have downloaded online for the Android seems to be polluted with malware, and I even reimaged my desktop because of all the crap I've tried.
Do you have a recommended tool for this that isn't some horrible marketing ploy? Minitool, Dr.Fone, FonePaw, and Kingoroot were all unsuccessful.
Also, if the data resides on an internal SD card, how is it formatted? I assume it is not a typical EXT or NTFS file system. Can you tell me which device I should be trying to recover from? It looks like /dev/block/mmcblk0p21.
If the internal storage is inaccessible, another thought I had was to do a block copy (with dd) onto a separate SD card, but I am unsure of whether this would provide a copy of the overwritten data, or would it actually reduce my chances of recovery.
The phone is a Samsung Galaxy On5 (SM-G550T).
Much of the data is non-critical, but some of it is unfortunately irreplaceable. Again, I'm really looking for a "yes" or "no" here, either data recovery is possible or not. And of course any suggestions on how to do it are greatly appreciated. The time it took to flash was almost instantaneous, but I also realize that flash drives are different from spinning drives in terms of how data is written and stored.
Thank you.

libertine5 said:
Hi.
I mistakenly flashed my Android Galaxy On5 (using Odin's "AP" option) with one of the Exynos files. I saw something about "userdata" and knew immediately I had made a mistake, even though I did not load anything in the Odin "userdata" option. Why I did this probably isn't relevant, but I'm happy to provide more detail.
My question, however, is a simple one: Having done this, is it still possible to recover the user data that is no longer visible on the phone? When I reboot the phone without TWRP, it looks like it has been factory reset.
The phone is rooted, and I can see the device shares with "df". I can't see any secondary SD card based on the information I found about it sitting on top of where the SIM card is installed. I have done plenty of computer data recoveries from hard disk.. But every tool I have downloaded online for the Android seems to be polluted with malware, and I even reimaged my desktop because of all the crap I've tried.
Do you have a recommended tool for this that isn't some horrible marketing ploy? Minitool, Dr.Fone, FonePaw, and Kingoroot were all unsuccessful.
Also, if the data resides on an internal SD card, how is it formatted? I assume it is not a typical EXT or NTFS file system. Can you tell me which device I should be trying to recover from? It looks like /dev/block/mmcblk0p21.
If the internal storage is inaccessible, another thought I had was to do a block copy (with dd) onto a separate SD card, but I am unsure of whether this would provide a copy of the overwritten data, or would it actually reduce my chances of recovery.
The phone is a Samsung Galaxy On5 (SM-G550T).
Much of the data is non-critical, but some of it is unfortunately irreplaceable. Again, I'm really looking for a "yes" or "no" here, either data recovery is possible or not. And of course any suggestions on how to do it are greatly appreciated. The time it took to flash was almost instantaneous, but I also realize that flash drives are different from spinning drives in terms of how data is written and stored.
Thank you.
Click to expand...
Click to collapse
If you haven't any advice on how to do it, just a simple "yes" or "no" as to whether a recovery is possible would be greatly appreciated. There must be a few forum readers out there who know the answer to that question. Anyone? Bueller?

libertine5 said:
If you haven't any advice on how to do it, just a simple "yes" or "no" as to whether a recovery is possible would be greatly appreciated. There must be a few forum readers out there who know the answer to that question. Anyone? Bueller?
Click to expand...
Click to collapse
If you wiped out userdata, that means all your data is gone. I know for computers, deleting data doesn't necessary delete the data, but rather makes the space unallocated, meaning new data can be written over it. Not 100% sure if they have something similar for Android. If you have google synced with your account, you can recover most of your data that way, otherwise you might be out of luck.

Understanfing partition on S7

Ok guys. I use custom ROM for a while know and I did some mistake that sometime I can fix sometime I can't.
Today I messed with backups and I need help.
I did a full backup using adb directly on my laptop (TWRP recovery).
I tried to restore it using adb restore backup comand line. It didn't worked, why memory got filed up, the phone wouldn't boot, neither on recovery or normal.
I succesfully managed to flash back TWRP using odin, and from there I flashed lineageOS and get my phone to boot.
Evrything was fine but... my external SD isn't regognize anymore, neither by lineage nor TWRP. It just didn't show anywhere, and when I try to mount it in TWRP, the box isn't checkable.
The card is fine, I've tested it on my laptop and on another phone.
So it's either a hardware issue and my phone is broken and it's OK I guess.
Or it's a software issue, and my restoring messed up something, a partition that I'm not aware of, that handles the sd card.
So my question is : what can I try to fix my problem ? And on a larger issue, what are exactly the different partitions on a S7 hardrive, what are their purpose, How can I restore them to their initial state ? How do I identify partition in TWRP ? In Odin ? In Heimdall (I'm a linux user) ? I know that there's something called MoDem, or EFS ? Can someone explain those or point me to a class that explain this ?

No harddrive. The EFS partition is especially important, it contains your phone's unique radio information such as your IMEI. Backup it as soon as possible, if you were to have a rainy day you will thank the stars you made that backup. You could try printing the partition table on ADB shell with gdisk and investigating it.

Wattsensi said:
No harddrive. The EFS partition is especially important, it contains your phone's unique radio information such as your IMEI. Backup it as soon as possible, if you were to have a rainy day you will thank the stars you made that backup. You could try printing the partition table on ADB shell with gdisk and investigating it.
Click to expand...
Click to collapse
df comand line and cat /proc/partition returns this. Can't say if it's right

Using gdisk on /dev/block/mmcblk0 you can print the exact GPT table in a human readable form :^)