Backup data from a bricked gs290

Devices
#1

as this day would not be shitty enough: my volla / gs290 suddenly died.
it will show the logo but not load sfos, screen remains blackish
the last thing i did was pkcon refresh / update
(i had some issues with installing an app from storeman)

i would like to copy one file from it
when i try to connect via putty as defaultuser i get this:

Pre-authentication banner message from server:
| "System is booting up. Unprivileged users are not permitted to log in yet. Pl

ease come back later. For technical details, see pam_nologin(8)."
End of banner message from server

now how could i connect ‘as root’ ? any ideas some one ?

in the end i do not care how i can achieve it: i just need to copy one file from internal storage

#2

some updates:
adb wont connect
adb devices and fastboot devices shows nothing.
but: sp flashtool seems to recognize the device.
so i could perfectly flash it (as usually)
but how would i now be able to connect to or backup / restore the file system ?

#3

i did open the scatter file and read back the data of

  • partition_index: SYS34
    partition_name: userdata

so i have now like 55 GB of data on my pc but 7zip wont open it. mounting as .img did fail on windows
any ideas ?

here is the basic howto: i do have a scatterfile already, thanks to flashing

#4

@piggz , do you have any hints how i could convert that stuff into something that i can actually browse and extract my keepass.db ?

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#5

Can you use a loop mount with an offset to mount home?

#6

hmm, i will try if it works in wsl2

#7

tried both, the readback file (userdata as read with sp flash tool) and the exported bin (the partition of userdata exported with wwr mkt) and failed
mount /mnt/c/Users/Tarija/Downloads/SP_Flash_Tool_v5.2208_Win/Readback-Trial/ROM_34.rom -o loop=/home /mnt

mount: /mnt: failed to setup loop device for /mnt/c/Users/Tarija/Downloads/SP_Flash_Tool_v5.2208_Win/Readback-Trial/ROM_34.rom.

when i try sfdisk on both files i get:
sfdisk: /mnt/c/Users/Tarija/Downloads/SP_Flash_Tool_v5.2208_Win/Readback-Trial/ROM_34.rom: does not contain a recognized partition table

am playing now with iat (iso analyzer tool)
tool runs for hours shows statements detect signature etc. but no file to see and no end
after hours then:
…
Detect Signature RAW 2 at -943650337
Detect Signature RAW 2 at -943650321
Image is broken
This image is not CD IMAGE

another trial with eporting the whole emmc_user using the start of spg as lengt

#8

first is the boot.img and maybe useless
second are the first 8 MB to read the table and get the values for start and length
third is the image itself

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after that, feed it into wwr mkt

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and running cut the rom, trim the zeros and keep userdata (that right bottom button)

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now i can see in windows mount in context menue on the img files but that failes.
so now i need to try in linux

leni@DESKTOP-62KDO04:~$ mount /mnt/c/Users/Tarija/Downloads/SP_Flash_Tool_v5.2208_Win/ReadBackAll/assembled/userdata.img /mnt/volla/ -o loop=/home
mount: /mnt/volla/: failed to setup loop device for /mnt/c/Users/Tarija/Downloads/SP_Flash_Tool_v5.2208_Win/ReadBackAll/assembled/userdata.img.

-t ext4 did not help neither

#9

@piggz i can open system.img with 7zip on windows, but not the userdata.img
any ideas ?
Thanks a lot !

image

but error on userdata.img
btw this is also the case with the images that i did use for flashing: system.img can be opened with 7zip, userdata not.

leni@DESKTOP-62KDO04:~$ sudo mount /mnt/c/Users/Tarija/Downloads/SP_Flash_Tool_v5.2208_Win/ReadBackAll/assembled/userdata.img /mnt/volla
mount: /mnt/volla: unknown filesystem type ‘LVM2_member’.

#10

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#11

fdisk userdata.img

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#13

@piggz couldn’t be the encryption the reason for not beeing able to mount userdata ?

#14

downloaded twrp recovery image and flashed it via sp flashtool
started phone to recovery mode and device was identified by wwr mtk !
(while adb devices in wsl would show nothing)
going to follow this and see what happens

running in wwr mtk
image

#15

ok, i did decrypt twice.
but none of the decrypted images shows any partitions.
while the original userimage seems to have them
wwr mtk shows them only for the org image