Any way to pull a local file from an Android 12 device stuck in Recovery before factory reset? (Unlocked bootloader) - Reddthat

My Tecno Spark 10 Pro (MediaTek Helio G88, Android 12) bootlooped after a banking app froze. Now it boots straight into stock recovery with the message that Android cannot be loaded and data may be corrupt. The bootloader is unlocked. I hooked it up to an Android tablet via OTG with Bugjaeger. The device uses A/B partitioning and was running on slot b. I switched it to slot a via fastboot, but slot a gives the exact same recovery loop, so the issue is clearly a corrupted userdata partition failing to mount during early init. All I need is my local KeePass database file from internal storage. I know modern Android uses File-Based Encryption with keys sealed in the TEE, but since my bootloader is unlocked, is there any known way via fastboot, MTK tools, or custom boot images to extract or decrypt that single file before I wipe the device? Or is it completely unrecoverable once the filesystem fails to mount?

29 points · 8 comments · view on lemmy.world

8 Comments

hexagonwin@lemmy.today · 3 pts · 15h (3 replies)

are you rooted?/do you get adb while booting? (few years ago on a custom rom's debug build, but i was able to connect via adb and read logcat and solve the issue it was having while stuck in bootloop and before it auto enters recovery)
i see you have custom recovery now. can you boot a custom recovery (maybe temporarily via fastboot)?

it should be possible to recover given that you have full unrestricted access to the device and even know the lockscreen password..

seems like it's possible with twrp. btw, i've bootlooped my phone before after using twrp to wipe dalvik cache on a recent encrypted phone (it created an unencrypted dir on userdata iirc, removing the offending directory solved it), so beware and don't do anything that doesn't seem necessary!

lipen@reddthat.com · 1 pts · 14h (2 replies)

I don't have root and I don't have custom recovery :)

hexagonwin@lemmy.today · 2 pts · 14h (1 reply)

maybe try booting this or this TWRP temporarily without flashing using fastboot (fastboot boot recovery_filename.img)

(kinda unlikely to be able to directly mount data though, there's one on 4PDA too dated Apr 2024 but it specifically says it doesn't support mounting data)

are you able to obtain the installed version of the firmware or extract stock boot image from device? (if the TWRP above booted, you probably can)

in that case, we may be able to enable adb during boot phase by changing some props on the boot image's initrd, and try logcat'ing to get android properly booting again.

lipen@reddthat.com · 1 pts · 10h

TWRP won't load :( The phone reboots and the error appears again

Shimitar@downonthestreet.eu · 3 pts · 16h (2 replies)

No, unfortunately there is no way. If recovery could mount and decrypt yes, otherwise no.

user224@lemmy.sdf.org · 4 pts · 15h (1 reply)

TWRP has that option, but a lot of people have said it doesn't work.

Shimitar@downonthestreet.eu · 2 pts · 12h

TWRP yes, but in that case it will ask for your pin code, mount and decrypt.

If the partition cannot be mounted, like in this case, it's just plain impossible no matter which recovery.

frongt@lemmy.zip · 2 pts · 15h

Can you dirty flash a ROM? But if it's really a corrupt user data partition, probably not recoverable with the tools at hand. Maybe if it's possible to take a dump of the device, then decrypt and run file recovery on the partition image.

But I'm not familiar with that process. If it's valuable to you, I'd pay a data recovery service.

Also, this is why you should have backups.