Hello there,
About year ago I've done an update to 6.0 android. Battery was charged near full and everything seemed okey. But, after update I faced a bootloop. So I tried to flash stock firmware and... failed. Many times. I'm unable to boot into recovery mode. Factory mode also isnt working. So, I tried to unlock my bootloader and flash another image, but when I try to unlock, I get a: "Check allow oem unlock in developer options". Sadly, I cant boot to check this option Is there any way to unlock oem without running android? What can I do? :crying:
Jaszka said:
Hello there,
About year ago I've done an update to 6.0 android. Battery was charged near full and everything seemed okey. But, after update I faced a bootloop. So I tried to flash stock firmware and... failed. Many times. I'm unable to boot into recovery mode. Factory mode also isnt working. So, I tried to unlock my bootloader and flash another image, but when I try to unlock, I get a: "Check allow oem unlock in developer options". Sadly, I cant boot to check this option Is there any way to unlock oem without running android? What can I do? :crying:
Click to expand...
Click to collapse
You can flash the /persist partition from a device which has had OEM Unlock previously enabled in Developer Options.
MotoJunkie01 said:
You can flash the /persist partition from a device which has had OEM Unlock previously enabled in Developer Options.
Click to expand...
Click to collapse
How can you flash the /persist partition in a device with a locked bootloader? Doesn't this contain other information as well?
I think the real problem here is either the OP is not using the correct factory firmware image, or incorrect user procedure.
acejavelin said:
How can you flash the /persist partition in a device with a locked bootloader? Doesn't this contain other information as well?
I think the real problem here is either the OP is not using the correct factory firmware image, or incorrect user procedure.
Click to expand...
Click to collapse
You are probably correct. Even with a locked bootloader, certain partitions can be flashed as long as downgrading is not detected. Example, if I have an xt1548 Moto G3 running on stock 5.1.1 firmware, and I have a locked bootloader, I can flash either an updated 6.0.1 stock firmware package or I can reflash the 5.1.1 firmware with the same build as the one already installed. The bootloader will, however, prevent downgrading. In flashing the /persist partition, the .img being flashed would need to be from an equal or newer build as well.
But again, your statement regarding the correct firmware procedure and/or correct firmware package is likely correct.
MotoJunkie01 said:
You are probably correct. Even with a locked bootloader, certain partitions can be flashed as long as downgrading is not detected. Example, if I have an xt1548 Moto G3 running on stock 5.1.1 firmware, and I have a locked bootloader, I can flash either an updated 6.0.1 stock firmware package or I can reflash the 5.1.1 firmware with the same build as the one already installed. The bootloader will, however, prevent downgrading. In flashing the /persist partition, the .img being flashed would need to be from an equal or newer build as well.
But again, your statement regarding the correct firmware procedure and/or correct firmware package is likely correct.
Click to expand...
Click to collapse
You can't flash anything except a bootloader. I was in this situation as MotoJunkie knows and nothing works. I did have a full backup of every partition on the phone and none flashed. Today I bricked it so badly that it doesn't even turn on anymore. My tip is to not mess with the bootloader and stuff and just use the phone normally as many things are encrypted on this phone.
purplefruity said:
You can't flash anything except a bootloader. I was in this situation as MotoJunkie knows and nothing works. I did have a full backup of every partition on the phone and none flashed. Today I bricked it so badly that it doesn't even turn on anymore. My tip is to not mess with the bootloader and stuff and just use the phone normally as many things are encrypted on this phone.
Click to expand...
Click to collapse
Yes I recall your situation and your hard brick. I'm saying that under normal circumstances you can flash full firmware packages with a locked bootloader, as long as downgrading is not attempted.
MotoJunkie01 said:
Yes I recall your situation and your hard brick. I'm saying that under normal circumstances you can flash full firmware packages with a locked bootloader, as long as downgrading is not attempted.
Click to expand...
Click to collapse
You can't flash regular ones too. It has to be a newer firmware for the locked bootloader to let it pass
purplefruity said:
You can't flash regular ones too. It has to be a newer firmware for the locked bootloader to let it pass
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Click to collapse
That's what I was saying. An equal or newer one. Downgrading isn't permitted.
MotoJunkie01 said:
That's what I was saying. An equal or newer one. Downgrading isn't permitted.
Click to expand...
Click to collapse
Mine was on marshmallow and it wouldn't want to flash marshmallow stock so what I was saying is that you can't go anywhere unless stock nougat is released for this device.
purplefruity said:
Mine was on marshmallow and it wouldn't want to flash marshmallow stock so what I was saying is that you can't go anywhere unless stock nougat is released for this device.
Click to expand...
Click to collapse
You obviously developed corrupt partitions some way or another. I flash stock firmware packages with a locked bootloader on a regular basis. You should always be able to flash the same firmware build that is currently installed on your device.
MotoJunkie01 said:
You obviously developed corrupt partitions some way or another. I flash stock firmware packages with a locked bootloader on a regular basis. You should always be able to flash the same firmware build that is currently installed on your device.
Click to expand...
Click to collapse
O well I guess my device was different then. Won't turn on at all now . Gonna sell it for parts so at least I get some money back.
Hi everyone, I hope I am posting this in the correct section, and if not, can an admin move my post to the appropriate place? I am a geek with PC's but mobile is new to me and I would like to root my device which is a Samsung Galaxy J3 (2018) version. I cannot find info here after searching. Here is what I achieved thus far. I downloaded what I think is the firmware file named FirmwareX.Net_J337WVLS2ASC1_J337WOYV2ASC1_PCM_8.0_Full which has my model number SM-J337W and part of build number in the filename. My build number fully is R16NW.J337WVLS2ASC1. The IMEI is 359229091474959.
I downloaded latest odin tool and just about to download TWRP and my model is not in their list and thats where I'm at. Can someone confirm if this is the actual stock firmware rom, and if I am ready to proceed and some steps would be appreciated. I was told by Oneclickroot service that they have a different stock firmware, and just wanted me to pay for something I can probably do on my own, so I'm puzzled by their reply as I had a very hard time finding this firmware which seems to be the closest match. Has anyone here ever rooted this particular device and provide me a sure step by step way to root it? I do have the setting options OEM Unlock and USB Debugging if that helps.
Bernard St-Pierre
ben480 said:
Hi everyone, I hope I am posting this in the correct section, and if not, can an admin move my post to the appropriate place? I am a geek with PC's but mobile is new to me and I would like to root my device which is a Samsung Galaxy J3 (2018) version. I cannot find info here after searching. Here is what I achieved thus far. I downloaded what I think is the firmware file named FirmwareX.Net_J337WVLS2ASC1_J337WOYV2ASC1_PCM_8.0_Full which has my model number SM-J337W and part of build number in the filename. My build number fully is R16NW.J337WVLS2ASC1. The IMEI is 359229091474959.
I downloaded latest odin tool and just about to download TWRP and my model is not in their list and thats where I'm at. Can someone confirm if this is the actual stock firmware rom, and if I am ready to proceed and some steps would be appreciated. I was told by Oneclickroot service that they have a different stock firmware, and just wanted me to pay for something I can probably do on my own, so I'm puzzled by their reply as I had a very hard time finding this firmware which seems to be the closest match. Has anyone here ever rooted this particular device and provide me a sure step by step way to root it? I do have the setting options OEM Unlock and USB Debugging if that helps.
Bernard St-Pierre
Click to expand...
Click to collapse
The stock firmware that you downloaded is for your model number but you need to verify that it works with your mobile carrier. If you downloaded the correct firmware for your region and your carrier.
There isn't a TWRP recovery or a known rooting method for your model number. You'll have to try the various universal rooting apps and the various rooting programs for PC and hope of them works.
Or you might can extract the boot.img from the stock firmware that you downloaded then use Magisk on PC to create a modified boot.img then flash that modified boot.img via Odin then reboot the device and install the Magisk root manager app on the device to gain root. If your bootloader is locked, you won't be able to flash the modified boot.img, you'll have to find a method to unlock your bootloader, if one exists for your model number, android version and build number.
Sent from my LGL84VL using Tapatalk
Droidriven said:
The stock firmware that you downloaded is for your model number but you need to verify that it works with your mobile carrier. If you downloaded the correct firmware for your region and your carrier.
There isn't a TWRP recovery or a known rooting method for your model number. You'll have to try the various universal rooting apps and the various rooting programs for PC and hope of them works.
Or you might can extract the boot.img from the stock firmware that you downloaded then use Magisk on PC to create a modified boot.img then flash that modified boot.img via Odin then reboot the device and install the Magisk root manager app on the device to gain root. If your bootloader is locked, you won't be able to flash the modified boot.img, you'll have to find a method to unlock your bootloader, if one exists for your model number, android version and build number.
Sent from my LGL84VL using Tapatalk
Click to expand...
Click to collapse
Thank you for the reply Droidriven, I thankfully have the option in settings to unlock the bootloader called "OEM Unlock" unlike most other J3's who do not. So basically, you are saying that I can root this device with Magisk with your suggested Magisk method correct? Could you elaborate this method step by step?
Bernard St-Pierre
ben480 said:
Thank you for the reply Droidriven, I thankfully have the option in settings to unlock the bootloader called "OEM Unlock" unlike most other J3's who do not. So basically, you are saying that I can root this device with Magisk with your suggested Magisk method correct? Could you elaborate this method step by step?
Bernard St-Pierre
Click to expand...
Click to collapse
I'll explain the "OEM unlock" setting a bit first. The OEM unlock setting does not necessarily unlock your bootloader. On some devices, enabling this setting unlocks bootloader but on most devices it does not actually unlock the bootloader, it only puts the device in a state that the bootloader "can" be unlocked using some form of unlock method after enabling the setting. In these cases, the unlock method would not work without enabling OEM unlock setting before implementing the unlock method.
So, basically, what I'm saying is that even though you have the OEM unlock setting, this does not necessarily mean that your bootloader is unlocked just by toggling this setting, it may still be locked even after toggling the setting. You'll have to verify whether your bootloader is actually unlocked or not. Do some Google searches for:
"Check bootloader status on Samsung devices"
This should give you results to find a method to verify your bootloader status.
Once you have verified that your bootloader is unlocked, you can use the Magisk rooting method. Read the "Boot Image Patching" section in the link below, there are also several other guides all over the internet and videos on YouTube that give instructions on patching your boot.img. As for actually flashing the boot.img, you will be flashing it using Odin. Use 7zip to compress the patched boot.img into a .tar compressed file. When you flash the file using Odin, place .tar file in the AP slot in Odin.
https://github.com/topjohnwu/Magisk/blob/master/docs/install.md
Sent from my LGL84VL using Tapatalk
My phone is boot-looping after i did android 9.0 update using odin.I had PrometheusOneUI V2.0 as a custom rom before but i had no imei and baseband so i needed that back so i downloaded the newest filmware of sammobile and i flashed the filmware using Odin.I got a pass but the phone is now bootlooping.When i go to download mode now FRP Lock and OEM lock are off.and when i try to flash root it now shows me <Only official released binaries are allowed to be flashed (Recovery)>.It wont let me flash anything other than the stock rom that results in bootlooping.Did anyone else have this problem,Can someone please help me with my bricked SM-J530F
kevin50206 said:
My phone is boot-looping after i did android 9.0 update using odin.I had PrometheusOneUI V2.0 as a custom rom before but i had no imei and baseband so i needed that back so i downloaded the newest filmware of sammobile and i flashed the filmware using Odin.I got a pass but the phone is now bootlooping.When i go to download mode now FRP Lock and OEM lock are off.and when i try to flash root it now shows me <Only official released binaries are allowed to be flashed (Recovery)>.It wont let me flash anything other than the stock rom that results in bootlooping.Did anyone else have this problem,Can someone please help me with my bricked SM-J530F
Click to expand...
Click to collapse
Flash the device via Odin, when it bootloop, turn the device off, then boot your device into stock recovery and then choose the factory reset option.
Sent from my SM-S767VL using Tapatalk
Droidriven said:
Flash the device via Odin, when it bootloop, turn the device off, then boot your device into stock recovery and then choose the factory reset option.
Sent from my SM-S767VL using Tapatalk
Click to expand...
Click to collapse
I already tried that and i wiped catch,i also tried another filmware form the uk still its bootlooping
kevin50206 said:
I already tried that and i wiped catch,i also tried another filmware form the uk still its bootlooping
Click to expand...
Click to collapse
Ok, you've got something else going on.
Have you previously modified the device or flashed anything on the device that wasn't stock? If so, did the modifications or whatever you flashed cause an issue and that is now the reason you are flashing the firmware?
Are you certain that your firmware is for your specific device and is it the most up to date version for your device?
Droidriven said:
Ok, you've got something else going on.
Have you previously modified the device or flashed anything on the device that wasn't stock? If so, did the modifications or whatever you flashed cause an issue and that is now the reason you are flashing the firmware?
Are you certain that your firmware is for your specific device and is it the most up to date version for your device?
Click to expand...
Click to collapse
Yes i matched the model number and no i was not running anything that isn't for it
kevin50206 said:
Yes i matched the model number and no i was not running anything that isn't for it
Click to expand...
Click to collapse
But are you using the most up to date firmware? Older/downgraded firmware won't work, it has to be exactly the same binary as what is already on the device or a firmware with a newer binary, it can not be a firmware that has an older binary than the firmware that is already on the device.
Sent from my SM-S767VL using Tapatalk
Hi guy I am panicking here I accidentally wiped everything from my samsung note 9 and there is no OS on the phone. I tried to flash older firmware but Odin is stuck at recovery and the phone shows a red line saying "SW REV. CHECK FAIL(BOOTLOADER) DEVICE: 6, BINARY:5
PLEASE SOMEONE HELP ME
Skulper said:
Hi guy I am panicking here I accidentally wiped everything from my samsung note 9 and there is no OS on the phone. I tried to flash older firmware but Odin is stuck at recovery and the phone shows a red line saying "SW REV. CHECK FAIL(BOOTLOADER) DEVICE: 6, BINARY:5
PLEASE SOMEONE HELP ME
Click to expand...
Click to collapse
The firmware that you flashed has a lower binary than the firmware that you had on the device before you modified it. You need to flash a firmware that has the same binary as what you had before you modified the device, or you need to flash a firmware that has a higher/newer binary than what you had.
See where the error says that your device is binary 6 but the firmware that you flashed has binary 5? You need a binary 6 or higher firmware. You can identify the binary by looking at the 5th character from the right end of the firmware build number.
Sent from my SM-S767VL using Tapatalk
Droidriven said:
The firmware that you flashed has a lower binary than the firmware that you had on the device before you modified it. You need to flash a firmware that has the same binary as what you had before you modified the device, or you need to flash a firmware that has a higher/newer binary than what you had.
See where the error says that your device is binary 6 but the firmware that you flashed has binary 5? You need a binary 6 or higher firmware. You can identify the binary by looking at the 5th character from the right end of the firmware build number.
Sent from my SM-S767VL using Tapatalk
Click to expand...
Click to collapse
i think i might be in love with you,(not in a weird way) this reply here saved my ass,i was stuck on odin wondering what was wrong & just this simple explanation helped me a lot
brokboi said:
i think i might be in love with you,(not in a weird way) this reply here saved my ass,i was stuck on odin wondering what was wrong & just this simple explanation helped me a lot
Click to expand...
Click to collapse
Be aware, once you flash a firmware that upgrades your device binary to a higher binary, you can not go back to the lower binary. A lot of times, flashing a firmware that upgrades the binary also upgrades the bootloader to a more secure bootloader that can't be unlocked, this kills virtually any chance of rooting the device or flashing TWRP custom recovery and/or custom ROMs. Then you're stuck with a device that you can't modify the way you want.
Droidriven said:
Be aware, once you flash a firmware that upgrades your device binary to a higher binary, you can not go back to the lower binary. A lot of times, flashing a firmware that upgrades the binary also upgrades the bootloader to a more secure bootloader that can't be unlocked, this kills virtually any chance of rooting the device or flashing TWRP custom recovery and/or custom ROMs. Then you're stuck with a device that you can't modify the way you want.
Click to expand...
Click to collapse
Ya i had that in mind so i flashed accordingly & i have unlocked bootloader with twrp not that i needed it though, cuz i just wanted to use samsung dex
brokboi said:
Ya i had that in mind so i flashed accordingly & i have unlocked bootloader with twrp not that i needed it though, cuz i just wanted to use samsung dex
Click to expand...
Click to collapse
Have you used TWRP to create a android backup of your stock ROM after you got it fixed? If not, do so, then store a copy of the backup on a PC or USB flashdrive, external sdcard, etc.. That backup can be used to restore your device, if needed.
Does anyone know how to downgrade bootloader in Samsung (M51)? I'm trying to rollback to OneUI 2.5 from 3.1 but it keeps giving me sw error
Wondering what sense it would make to downgrade phone's bootloader:
A bootloader helps to load the operating system or runtime environment to add programs to memory and provide access for components. It is needed to run the startup process, initialize the hardware, and pass control to the kernel, which initializes the operating system.
AlanDias17 said:
Does anyone know how to downgrade bootloader in Samsung (M51)? I'm trying to rollback to OneUI 2.5 from 3.1 but it keeps giving me sw error
Click to expand...
Click to collapse
No, you can't downgrade bootloader on Samsung unless the downgraded bootloader has a binary version equal to the binary version of your currently installed bootloader. For example, if the binary version of your currently installed bootloader is binary 4, you can flash the downgraded bootloader if it is also binary 4 but you cannot flash a bootloader that is binary 3, 2 or 1.
xXx yYy said:
Wondering what sense it would make to downgrade phone's bootloader:
A bootloader helps to load the operating system or runtime environment to add programs to memory and provide access for components. It is needed to run the startup process, initialize the hardware, and pass control to the kernel, which initializes the operating system.
Click to expand...
Click to collapse
Downgrading bootloader in order to flash custom recovery or root the device is a common practice if the currently installed bootloader can't be unlocked or does not allow flashing TWRP or rooting.
xXx yYy said:
Wondering what sense it would make to downgrade phone's bootloader:
A bootloader helps to load the operating system or runtime environment to add programs to memory and provide access for components. It is needed to run the startup process, initialize the hardware, and pass control to the kernel, which initializes the operating system.
Click to expand...
Click to collapse
Rationally speaking I'd rather stay on stable version of Android 10 OneUI 2.5 than on Android 11 OneUI 3.1. For me, it's buggy and camera quality got worsen. Updated bootloader isn't the issue but it's the reason I can't downgrade my OS.
Droidriven said:
No, you can't downgrade bootloader on Samsung unless the downgraded bootloader has a binary version equal to the binary version of your currently installed bootloader.
Click to expand...
Click to collapse
So now it's impossible in my situation since bootloader versions don't match since September security patch. Now that sucks.
AlanDias17 said:
So now it's impossible in my situation since bootloader versions don't match since September security patch. Now that sucks.
Click to expand...
Click to collapse
That is usually the case for Samsung owners. In the past, downgrading was possible but not on today's device's. It is rare and few and far between that a Samsung can be downgraded these days. Virtually impossible across the board. This is something to consider when buying Samsung devices and when a stock update is possible.
Me personally, I never update a device with stock updates unless things start having issues or stop working due to not updating to keep up with changing technology. I don't update unless absolutely necessary, I put the update off as long as possible.
My current device has been notifying me for months that an update is available but I have it paused so that it doesn't download. Maybe I'll update at some point in the future, maybe not.
AlanDias17 said:
So now it's impossible in my situation since bootloader versions don't match since September security patch. Now that sucks.
Click to expand...
Click to collapse
There is one potential workaround to downgrade, you can try extracting the system.img from the downgraded firmware then convert it to an Odin flashable .tar using 7zip to compress the file .tar format, select the highest level of compression. After extracting the system.img but before converting to .tar, try extracting the system.img itself then find where the kernel is packaged in the system.img then try finding what the binary version of the kernel is, if the kernel's binary version is lower than the binary version of the currently installed kernel, you will not be able to flash the extracted system.img with the kernel packaged inside it, you will have to try removing it then convert to .tar as I described. Once you verified binary versions, convert the file to .tar then flash the system.img.tar.md5 via Odin, place the system.img.tar.md5 in the AP slot.
Basically, it works like this, if you boot into download mode and look at the revision values, you should see something like this:
swREV B: x K: x S: x
B is for bootloader binary version, K is for kernel binary version and S is for system binary version. If B is lower than your currently installed B version, you can't flash it, if K is lower than your currently installed K version, you can't flash it, if S is lower than your currently installed S version, you can't flash it. See if you can find out what the binary version of your currently installed bootloader, kernel and system are, then compare them to the binary version of the downgraded firmwares bootloader, kernel and system. B, K and S can be independent different values, for example, a firmware could have a B value of 4, a K value of 6 and a S value of 5, they do not always all 3 have the same value in a single firmware. Some updates may come with an updated B binary and an updated K binary but not an S binary, or any combination. In my example above, if a device has values of B: 4 K:6 S:5 and that device receives an update that has B:5 and S7 but no updated K value, after flashing, the device would have B:5 K:6 and S:7.
If any of the parts of the downgraded firmware have a binary version that is equal to its corresponding currently installed component, it can be flashed, but if any of them are lower than their corresponding currently installed components, they can't be flashed.
Sorry to be so long winded, just trying to explain how binary version works and can possibly be manipulated to downgrade each individual element, if the binary versions correspond correctl.
Droidriven said:
There is one potential workaround to downgrade, you can try extracting the system.img from the downgraded firmware then convert it to an Odin flashable .tar using 7zip to compress the file .tar format, select the highest level of compression. After extracting the system.img but before converting to .tar, try extracting the system.img itself then find where the kernel is packaged in the system.img then try finding what the binary version of the kernel is, if the kernel's binary version is lower than the binary version of the currently installed kernel, you will not be able to flash the extracted system.img with the kernel packaged inside it, you will have to try removing it then convert to .tar as I described. Once you verified binary versions, convert the file to .tar then flash the system.img.tar.md5 via Odin, place the system.img.tar.md5 in the AP slot.
Basically, it works like this, if you boot into download mode and look at the revision values, you should see something like this:
swREV B: x K: x S: x
B is for bootloader binary version, K is for kernel binary version and S is for system binary version. If B is lower than your currently installed B version, you can't flash it, if K is lower than your currently installed K version, you can't flash it, if S is lower than your currently installed S version, you can't flash it. See if you can find out what the binary version of your currently installed bootloader, kernel and system are, then compare them to the binary version of the downgraded firmwares bootloader, kernel and system. B, K and S can be independent different values, for example, a firmware could have a B value of 4, a K value of 6 and a S value of 5, they do not always all 3 have the same value in a single firmware. Some updates may come with an updated B binary and an updated K binary but not an S binary, or any combination. In my example above, if a device has values of B: 4 K:6 S:5 and that device receives an update that has B:5 and S7 but no updated K value, after flashing, the device would have B:5 K:6 and S:7.
If any of the parts of the downgraded firmware have a binary version that is equal to its corresponding currently installed component, it can be flashed, but if any of them are lower than their corresponding currently installed components, they can't be flashed.
Sorry to be so long winded, just trying to explain how binary version works and can possibly be manipulated to downgrade each individual element, if the binary versions correspond correctl.
Click to expand...
Click to collapse
can you try If it is possible to downgrade like this, I would like to downgrade the s10e and s7 versions. It would be great if you could make a guide for it.
kullanici32 said:
can you try If it is possible to downgrade like this, I would like to downgrade the s10e and s7 versions. It would be great if you could make a guide for it.
Click to expand...
Click to collapse
I don't think you get the bigger picture.
I was not saying "you absolutely CAN downgrade if you do it like this".
I was saying "IF it is even possible, you can TRY doing it like this".
I don't know if it would work or not on your specific model number, there are too many variables involved in whether it will be successful or not.
I don't own this specific model number so I cant test anything to see if it will work, not to mention that I'm not doing all that research or putting that kind of time, work and energy into making anything for a device that I don't own or use.
I've just given the idea and "possibility" of downgrading based on how some other Samsung devices have been able to successfully downgrade the OS(system) by extracting the system.img from the downgraded firmware and flashing the system.img by itself without flashing the rest of the firmware. This is not the same as downgrading the whole firmware, you're only replacing the upgraded system with the previous version of system but only "IF" the binary versions for system and kernel do not conflict.
If you want to know how to do this or if it will even work on your specific model number, you will have to do your own research, your own thinking and your own hard work to figure it out based on how other Samsung owners have done it.
There are threads here that describe doing this on various other Samsung models. They don't all go about it exactly the same, there are differences in the details and methods based on various device specific software requirements and restrictions. You might or might not be successful, you could even brick your device if you get something wrong. Find other threads that describe how others did it and then try the methods that they used but use your firmware files to make the changes that they made.
Droidriven said:
I don't think you get the bigger picture.
I was not saying "you absolutely CAN downgrade if you do it like this".
I was saying "IF it is even possible, you can TRY doing it like this".
I don't know if it would work or not on your specific model number, there are too many variables involved in whether it will be successful or not.
I don't own this specific model number so I cant test anything to see if it will work, not to mention that I'm not doing all that research or putting that kind of time, work and energy into making anything for a device that I don't own or use.
I've just given the idea and "possibility" of downgrading based on how some other Samsung devices have been able to successfully downgrade the OS(system) by extracting the system.img from the downgraded firmware and flashing the system.img by itself without flashing the rest of the firmware. This is not the same as downgrading the whole firmware, you're only replacing the upgraded system with the previous version of system but only "IF" the binary versions for system and kernel do not conflict.
If you want to know how to do this or if it will even work on your specific model number, you will have to do your own research, your own thinking and your own hard work to figure it out based on how other Samsung owners have done it.
There are threads here that describe doing this on various other Samsung models. They don't all go about it exactly the same, there are differences in the details and methods based on various device specific software requirements and restrictions. You might or might not be successful, you could even brick your device if you get something wrong. Find other threads that describe how others did it and then try the methods that they used but use your firmware files to make the changes that they made.
Click to expand...
Click to collapse
Can you put or give us a link to such a thread or post, we will follow the steps for our own device firmware.
What would be a way to use a TWRP backup with a v3 on a device that has say a v5 boot
Packtlike said:
What would be a way to use a TWRP backup with a v3 on a device that has say a v5 boot
Click to expand...
Click to collapse
If using TWRP, you should, "in theory", be able to flash whatever you want, including an older backup.
Droidriven said:
After extracting the system.img but before converting to .tar, try extracting the system.img itself then find where the kernel is packaged in the system.img
Click to expand...
Click to collapse
Could you please explain how do I go about "extracting the system.img iself"?
Droidriven said:
No, you can't downgrade bootloader on Samsung unless the downgraded bootloader has a binary version equal to the binary version of your currently installed bootloader. For example, if the binary version of your currently installed bootloader is binary 4, you can flash the downgraded bootloader if it is also binary 4 but you cannot flash a bootloader that is binary 3, 2 or 1.
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What does "unless" mean in the first sentence above? I mean, if the only possibility for replacing an installed bootloader is using another bootloader with equal or higher binary version, then we are not downgrading anything, or are we? I am a bit confused.
zogoibi said:
Could you please explain how do I go about "extracting the system.img iself"?
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Extract the contents from the firmware file to get to the various .img/bin files in the firmware, find the system.img file, extract it's contents to get to the various files/folders in the system img. Then you find whatever parts of the system.img that you want/need then do whatever it is that you need to do with them.
zogoibi said:
What does "unless" mean in the first sentence above? I mean, if the only possibility for replacing an installed bootloader is using another bootloader with equal or higher binary version, then we are not downgrading anything, or are we? I am a bit confused.
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It means that it is possible to have a firmware that has a lower "bootloader" version than the firmware currently installed on a device but an equal "binary"version as the firmware currently installed. For example, if a device has firmware installed on it that has bootloader "y" with binary 4, they could flash a firmware that has bootloader "x"(x being lower than y) and the same binary 4, equivalent binary but lower actual bootloader version, which downgrades the bootloader version but not the binary version. If it had bootloader "x" but had binary 3 or lower, then, yes, what you say would apply.
Droidriven said:
Extract the contents from the firmware file to get to the various .img/bin files in the firmware, find the system.img file, extract it's contents to get to the various files/folders in the system img. Then you find whatever parts of the system.img that you want/need then do whatever it is that you need to do with them.
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Thank you. I already got that I have to gut apart system.img. But my question was: how do I do that? Anyway, I already found the answer: using simg2img command to transform system.img to raw format, then loopmounting it. But now, how do I find the kernel file as per your comment above: "find where the kernel is packaged in the system.img" ? There are one thousand files inside, and none of them seem to qualify as the kernel. Besides, on a developer forum I've read that the kernel is not inside system.img, but inside boot.img. And how to gut apart boot.img?
After a good deal of search, it seems I got the answer to that question too: getting a copy of android_booting_tools, which has the command unpackbootimg (since abootimg couldn't do the job and exited with error "not a valid Android Boot image") Once unpacked boot.img, voilá, the kernel is there (and definitely not inside system.img): the file named boot.img-zimage.
BUT!! Now, what do I want the kernel file for, if what I need is to downgrade the bootloader? Your instructions are a bit unclear in that point.
Droidriven said:
It means that it is possible to have a firmware that has a lower "bootloader" version than the firmware currently installed on a device but an equal "binary"version as the firmware currently installed. For example, if a device has firmware installed on it that has bootloader "y" with binary 4, they could flash a firmware that has bootloader "x"(x being lower than y) and the same binary 4, equivalent binary but lower actual bootloader version, which downgrades the bootloader version but not the binary version. If it had bootloader "x" but had binary 3 or lower, then, yes, what you say would apply.
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OK. I think I understood this part. Thanks.
zogoibi said:
Thank you. I understood what you meant: gut apart system.img. But my question was: how do I do that? Anyway, I already found the answer: using simg2img command to transform system.img to raw format, then loopmounting it. But now, how do I find the kernel as per your comment above: "find where the kernel is packaged in the system.img" ? There are one thousand files inside, and none of them seem to qualify as the kernel. Besides, as I've searched out there, in a developer forum I've read that the kernel is not in system.img, but in boot.img. And how to gut apart boot.img?
It seems I got the answer to that question either: downloading android_booting_tools, which has the command unpackbootimg (since abootimg couldn't do the job and exited with error "not a valid Android Boot image") Once unpacked boot.img, voilá, the kernel is there (and definitely not in system.img): the file named boot.img-zimage.
BUT!! Now, what the heck do I do with the kernel file, if what I need is to downgrade the bootloader? Your instructions are a bit unclear in that point.
OK. I think I understood this part. Thanks.
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I use 7zip.
You asked how to extract the system.img, not the kernel.
The boot.img is not the bootloader. If you're trying to downgrade the bootloader then you should be trying to use the bootloader, but you may or may not need other parts of the downgraded firmware also in order for the bootloader to not cause the device to hard rock or block the flash. What you would or wouldn't need, I don't know, it usually requires tinkering to find the right recipe. Trial and error, experimenting with mixing different parts of each firmware to see what will or won't work together.
Also, it may require unlocking the bootloader and/or using a modified version of Odin to flash a modified firmware or modified .img files.
That is all "IF" it is even possible or safe to attempt Your milage may vary.
Droidriven said:
You asked how to extract the system.img, not the kernel.
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I begun by quoting a post where you supposedly explained a 'potential' workaround for downgrading the bootloader (I qhote: "there is one potential workaround to downgrade"). As per your instructions, one should first extract 'system.img itself' in order to get hold of the kernel. And that's why I asked how to do it. Obviously the end point was to find the kernel, as per your instructions. But it turned out the kernel is not in system.img. I wonder what Is, then, the point in that part of your instructions.
Droidriven said:
The boot.img is not the bootloader.
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Obviously not. I haven't said that. I just said that I found out that kernel is inside boot.img, not inside system.img.
Droidriven said:
If you're trying to downgrade the bootloader then you should be trying to use the bootloader
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Well, I can also say: "if you're trying to help people downgrading the bootloader (which is the title of this thread), then you should be trying to help people downgrading the bootloader."
Droidriven said:
There is one potential workaround to downgrade, you can try extracting the system.img from the downgraded firmware then convert it to an Odin flashable .tar using 7zip to compress the file .tar format, select the highest level of compression. After extracting the system.img but before converting to .tar, try extracting the system.img itself then find where the kernel is packaged in the system.img then try finding what the binary version of the kernel is, if the kernel's binary version is lower than the binary version of the currently installed kernel, you will not be able to flash the extracted system.img with the kernel packaged inside it, you will have to try removing it then convert to .tar as I described. Once you verified binary versions, convert the file to .tar then flash the system.img.tar.md5 via Odin, place the system.img.tar.md5 in the AP slot.
Basically, it works like this, if you boot into download mode and look at the revision values, you should see something like this:
swREV B: x K: x S: x
B is for bootloader binary version, K is for kernel binary version and S is for system binary version. If B is lower than your currently installed B version, you can't flash it, if K is lower than your currently installed K version, you can't flash it, if S is lower than your currently installed S version, you can't flash it. See if you can find out what the binary version of your currently installed bootloader, kernel and system are, then compare them to the binary version of the downgraded firmwares bootloader, kernel and system. B, K and S can be independent different values, for example, a firmware could have a B value of 4, a K value of 6 and a S value of 5, they do not always all 3 have the same value in a single firmware. Some updates may come with an updated B binary and an updated K binary but not an S binary, or any combination. In my example above, if a device has values of B: 4 K:6 S:5 and that device receives an update that has B:5 and S7 but no updated K value, after flashing, the device would have B:5 K:6 and S:7.
If any of the parts of the downgraded firmware have a binary version that is equal to its corresponding currently installed component, it can be flashed, but if any of them are lower than their corresponding currently installed components, they can't be flashed.
Sorry to be so long winded, just trying to explain how binary version works and can possibly be manipulated to downgrade each individual element, if the binary versions correspond correctl.
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Hi, I know this thread is quite old. But i have a Rooted Galaxy M23 (SM-M236B) and in odin it says B:2 K:2 S:2. I was waiting for an software update and sawed that there was one update in that it says that is bit is 3, Questions: 1. If I install the bit 3 software i would not be able to install again a 2 bit software? 2. My bootloader is unlocked, does applying the update locks the bootloader? And 3. How do I know if the update makes my bootloader locked permanently?
Mr. Electrinix said:
Hi, I know this thread is quite old. But i have a Rooted Galaxy M23 (SM-M236B) and in odin it says B:2 K:2 S:2. I was waiting for an software update and sawed that there was one update in that it says that is bit is 3, Questions: 1. If I install the bit 3 software i would not be able to install again a 2 bit software? 2. My bootloader is unlocked, does applying the update locks the bootloader? And 3. How do I know if the update makes my bootloader locked permanently?
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1) yes, if you flash the binary 3 update, you will not be able to downgrade to a 2 binary, UNLESS the bootloader is unlocked and you use "patched Odin" or Cosmy's Odin to flash the downgraded firmware.
2) I don't know if flashing the update will lock the bootloader or not, you would have to research that yourself to see what results other users of your exact same model got after flashing the exact same update build number that your update has.
3) You would have to find other users that have the exact same model number device that you have and find a user that has flashed the exact update that you are asking about.
***Note***
If the update that you are asking about is a atock OTA update via the system update option in system settings, you will have to unroot the device then boot into recovery and wipe the cache partition (but not factory reset) then reboot the device, then do the update via settings. Stock OTA updates cannot safely be applied on devices that have been rooted, modified system partition or have custom recovery installed. You have to have clean, unrooted, unmodified stock firmware with stock recovery.
If you are manually flashing the update via Odin, you do not need to unroot before flashing the update, flashing via Odin "should" take care of that for you, depending on whether the update is a full update with a new system partition or a partial, incremental update.
Droidriven said:
1) yes, if you flash the binary 3 update, you will not be able to downgrade to a 2 binary, UNLESS the bootloader is unlocked and you use "patched Odin" or Cosmy's Odin to flash the downgraded firmware.
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You can NEVER downgrade the bootloader/binary/bit level, even if you've bootloader unlocked it. OEM Unlock does NOT magically enable you to downgrade the binary