amba_fwpack fails with Error: Detection finished with unusual entry sizes, verify files

[mprevot]

Trying to unpack firmware from gopro session 5 / 5 black (publicly available) with python3 amba_fwpak.py -m camera_loaders.bin -x, but it fails with

Error: Detection finished with unusual entry sizes, verify files

This firmware for an ambarella A9SE7 (https://github.com/hypoxic/GoPro-Research), so I thought this should work.

If not, how to adapt or correct amba_fwpack.py ? Any hints ?

[mefistotelis]

Ambarella provides SDK for device makers, which they modify to create SW for their products.

If the tool doesn't recognize the specific container, use search option to just recognize partitions - the partition markers never change.

[mprevot]

Unfortunately, amba_fwpak.py fails to find the pattern epos = fwmdlmm.find(b'\x90\xEB\x24\xA3' and exits silently.
So it seems partitions are different. If so, how to find the correct partition pattern ?

dji-firmware-tools/amba_fwpak.py

Line 546 in 156a1f9

epos = fwmdlmm.find(b'\x90\xEB\x24\xA3', epos+sizeof(FwModPartHeader))

fw for repro:

https://gopro.com/en/us/support/hero5-session-product-update/windows
or
https://1drv.ms/u/c/d9842e22f46d2655/Ea7woPSqngpHj7s4uRQN-FsBXzNBmrs-jCT2I8wNSDF1dg?e=Xibwvg

[mefistotelis]

Unfortunately, amba_fwpak.py fails to find the pattern

Not sure what to tell you..:

# ./amba_fwpak.py --fwmdlfile camera_firmware.bin -s
camera_firmware.bin: Extracting entry  0, pos      236, len   234222 bytes
camera_firmware.bin: Extracting entry  1, pos   234714, len    11176 bytes
camera_firmware.bin: Extracting entry  2, pos   246146, len  7999488 bytes
camera_firmware.bin: Extracting entry  3, pos  8245890, len 45473248 bytes
camera_firmware.bin: Extracting entry  4, pos 53719394, len 11026432 bytes
camera_firmware.bin: Extracting entry  5, pos 64746082, len  5669000 bytes
camera_firmware.bin: Extracting entry  6, pos 70415338, len 35913728 bytes

That's on file from the link hero5-session-product-update/windows.

Some header fields are clearly incorrect - header format is different. But the partitions are extracted.