Access /system/ while in recovery to stop bootloop - Samsung Galaxy S9+ Questions & Answers

Hello! I was editing the build.prop file on my Samsung S9+, and there must be a typo somewhere, because it went into a bootloop. I am able to boot into TWRP, so i was wondering if anyone has a method to possibly access /system/ while in recovery to undo what i did? I have a backup of the build.prop file.
If that isn't possible, would an Odin flash with HOME_CSC_*** fix it?
I would like to keep my data.
Thanks.

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[Q] MTK6573 custom recovery and backups / Stock Boot, Recovery + Scatter included

Phone is a Star X19i
Now I'm looking at getting a system to allow me to back up the rom and re-flash if needed.
Post 4 has attachments of my boot, recovery and scatter files.
Old issue: (Solved)
Stupid thing I did I renamed the mtklockscreen.odex to mtklockscreen.odex1 just as a test in a half asleep phase to see if I would get the stock lockscreen loading.
Suffice to say the phone no longer boots.
Really don't think I can get into ADB and rename the file to get the phone booting again unless anyone knows a way.
Android was 2.3.6 and I asked the seller if it was possible to get the rom incase anything like happened which they didn't.
So anyone have any ideas?
I have attached the stock recovery and boot images made with cat and a scatter file I made to post 4.
As I have no idea about modifying these for hard root can anyone take a look?
I don't know the specifics of the phone, but if you can go into recovery mode maybe you can get adb working, or use a flashable zip to rename the file by installing it from recovery (just need to edit the zips' updater script)
dxppxd said:
I don't know the specifics of the phone, but if you can go into recovery mode maybe you can get adb working, or use a flashable zip to rename the file by installing it from recovery (just need to edit the zips' updater script)
Click to expand...
Click to collapse
I got into built in Factory mode and can see the file I renamed through ADB and android commander but cannot rename it back due to not having hard root access.
I also have a copy of the boot and recovery partitions 5 and 6 respectively I made in the adb shell yesterday as I was half looking at getting hard root access.
ren mtklockscreen.odex1 mtklockscreen.odex
ren: permission denied
I read you can do a custom recovery with root using SP Tools still so can anyone help me do this?
I know about system root etc and stuff and have flashed roms before on other tablets and have been a PC I.T tech (wouldn't think it due to the stupid mistake) but this recovery and scatter files etc is kinda new to me.
I have a scatter file now I just made if anyone is interested in helping me.
Yes I have a MTK6573 but the scatter file came from the MT6516 Rom Studio which I read works the same for the 6573.
Attached is also my stock boot and recovery partitions I made with cat yesterday if there usable to anyone to help.
Well I got it working and fixed.
I had to go into adb shell and su and mount the file system as writable, as I have used linux before I didn't know about android and what needed to be done and permission locks etc.
The stock boot, recovery and scatter files will remain on this thread if anyone wants to help create or find a recovery which can allow me to create backups and flash custom roms.
I may be able to provide a dump of android 2.3.6 for those that want it once I'm provided with a backup solution as I have read a few people wanting this updated android rom.
This got too close to what I would like liked with bricking this phone.
And I'm not comfortable unless I have a rom backup of this.
Rooting Advice: For anyone with a MTK6573 on Android 2.3.6 trying to root but having issues with super one click make sure you only turn on USB debugging after Android has loaded and just before you plug the usb cable in to run super one click.
I have seen a few thread and posters here about not being able to root the phone and this is the cause that debug needs to be switched on right before you connect and try to root.
Original seller has agreed to send the firmware and flashing stuff on cd for me so I can upload it for you all.
This is a win for MTK6573 Star X19i owners as I'll have the updated 2.3.6 Gingerbread firmware to release for you all root modify etc in a week or so.
Be careful with ROM studio. I believe it is not compatible with MT6573.
You want to read this: http://bm-smartphone-reviews.blogspot.com/2012_04_01_archive.html
cybermaus said:
Be careful with ROM studio. I believe it is not compatible with MT6573.
You want to read this: http://bm-smartphone-reviews.blogspot.com/2012_04_01_archive.html
Click to expand...
Click to collapse
That's what I read and did to get my scatter as I used cat then used the program linked in that thread to generate the scatter.

[Q] I broke it

Hi guys!
I was hoping one of you could help me.
Yesterday i modified a build.prop file on my NextBook EBM8000ND (Next800T) tablet, causing it to get stuck in a bootloop every time it's turned on. I've been searching the Internet all day long but it's hard to find support when you have a device which no one in the world uses . It was rooted but I did a factory reset hoping that it would fix it. It didn't and now it's also unrooted. I tried to make a custom update.zip with the backup of the original build.prop file but the stock recovery simply refuses to load any update file. It always stops at verification. I used 7zip with store option. I tried signing the zip, I even edited the updater script to only print some text on the screen but the recovery still wouldn't load it. I tried to find a way to install CWM using sdcard but with no luck. When i tried to use ADB in recovery the device says: "failed to open driver control: No such file or directory". It might be worth mentioning that I found my device's ROM online with boot.img and recovery.img files and a .tar file which contains the original system folder.
Is there any way to make the stock recovery (since installing CWM or TWRP seems impossible) read my update file? Or is there another way to fix this? I only need to replace that single file.
Hoping to get help soon.
Cheers!

Is it possible to modify system files after flashing a firmware?

Hi, I have a rooted Lenovo B device (Mediatek M6735M) with TWRP recovery. I tried to change some build.prop values using an editor app but the result was I bricked my phone (and had to flash stock firmware again). Now, I wonder if and how I can apply some changes to the system files after flashing the firmware.
I want to ask you: is it possible to modify sys/system files after the firmware has been flashed (even the read-only ones), or is pre-flash manipulation the only solution? For example: is it safe to pull a system file with adb, modify it, then push it to the phone with adb?
Black Heretic said:
Hi, I have a rooted Lenovo B device (Mediatek M6735M) with TWRP recovery. I tried to change some build.prop values using an editor app but the result was I bricked my phone (and had to flash stock firmware again). Now, I wonder if and how I can apply some changes to the system files after flashing the firmware.
I want to ask you: is it possible to modify sys/system files after the firmware has been flashed (even the read-only ones), or is pre-flash manipulation the only solution? For example: is it safe to pull a system file with adb, modify it, then push it to the phone with adb?
Click to expand...
Click to collapse
No. You want to root your android again to do these.
Ashwinrg said:
No. You want to root your android again to do these.
Click to expand...
Click to collapse
I forgot to say that I rooted the phone again. I'd like to know if it is possible to edit system files after flashing a firmware (and rooting the phone) or if I'm forced to apply all system changes before flashing. Also, I'd like to know what kind of changes are allowed and/or forbidden (in order to avoid another brick).
For example, I found a read-only "serialno" file in "sys" folder and this file contains the serial number of the device. Could I pull this file with adb, change the content of this file (with another serial number) then push it into the phone?
Black Heretic said:
I forgot to say that I rooted the phone again. I'd like to know if it is possible to edit system files after flashing a firmware (and rooting the phone) or if I'm forced to apply all system changes before flashing. Also, I'd like to know what kind of changes are allowed and/or forbidden (in order to avoid another brick).
For example, I found a read-only "serialno" file in "sys" folder and this file contains the serial number of the device. Could I pull this file with adb, change this file (with another serial number) then push it into the phone?
Click to expand...
Click to collapse
You can change anything after rooting your phone. Make sure you are doing it correctly. Keep nandroid backup to recover from bad scenarios.
Ashwinrg said:
You can change anything after rooting your phone. Make sure you are doing it correctly. Keep nandroid backup to recover from bad scenarios.
Click to expand...
Click to collapse
Ok, but I'd like to have some general tips or advices before doing that. For example, I read (somewhere, here on xda) that file permissions have to be the same as the original file, so if I edit a read-only file I have to restore its read-only status or I could brick the phone. Is this true?
Black Heretic said:
Ok, but I'd like to have some general tips or advices before doing that. For example, I read (somewhere, here on xda) that file permissions have to be the same as the original file, so if I edit a read-only file I have to restore its read-only status or I could brick the phone. Is this true?
Click to expand...
Click to collapse
Yes. If you change permission to read-write then after modification you want change permission to read-only.
Grab ithat build.prop file and transfer to memory card using TWRP. Edit at PC and restore it

[problem] Phone stuck in a bootloop after editing build.prop (rooted with custom rec)

Dear fellas,
I replaced my build.prop file to an another one and my phone is not booting up anymore.
I have a rooted Xiaomi Mi 5s Plus, with custom recovery.
Can anyone advise what to do without wiping the phone completely and flashing a new ROM?
What I've tried doing:
- I had the original build.prop that the phone had before it got stuck.
- I used the file explorer in custom recovery, copied that file to the system folder in root.
- Rebooted the device, still no luck!
- After rebooting, when I reopen the recovery, and navigate to the system folder again, I don't find the file I copied to the system folder!
Any thoughts on the matter please? Thanks in advance!
Have you tried writing original Rom to the phone. Don't have much experience with that kind best I can suggest
Sent from my SM-G930V using Tapatalk
black_hawk1990 said:
Dear fellas,
I replaced my build.prop file to an another one and my phone is not booting up anymore.
I have a rooted Xiaomi Mi 5s Plus, with custom recovery.
Can anyone advise what to do without wiping the phone completely and flashing a new ROM?
What I've tried doing:
- I had the original build.prop that the phone had before it got stuck.
- I used the file explorer in custom recovery, copied that file to the system folder in root.
- Rebooted the device, still no luck!
- After rebooting, when I reopen the recovery, and navigate to the system folder again, I don't find the file I copied to the system folder!
Any thoughts on the matter please? Thanks in advance!
Click to expand...
Click to collapse
Try mount system read/write first then copy og build prop file in system partition and reboot or use aroma file manager.

Tweaking system file permissions via TWRP possible?

Is it possible to edit file permissions of voltage_max file located in sys/class/power_supply/battery via TWRP? In TWRP's File Manager I can only get to battery and no further. It's seemingly shown as a file instead of a folder.
And more importantly if its possible will the tweaked file permissions stick after booting into the ROM? I know with root access it's easy just wanted to know if via recovery it can be accomplished w/o root or not?
Thanks.
Bump.
Anyone?

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