BackDoorLock hack - prevents silent updates

[NiLuJe]

@knc1: IIRC, the issue was mainly with memory-starved DXs (128MB and a larger screen, meeep). Anything else is mostly okay, but the option has been left in the KUAL extension just in case .

[Signum98]

To activate the hack i have to press "lock the backdoor" or "lock state"?

[knc1]

Originally Posted by Signum98

To activate the hack i have to press "lock the backdoor" or "lock state"?

"lock state" is a query
"lock the backdoor" is a command

- - - -

Note: Known not to be effective on 5.6.x firmware versions.
Most likely not effective on 5.7.x firmware versions either.

Just keep it in 'airplane mode' until we get a chance to test the alternative OTA blockers.

[Signum98]

Thanks

[odamizu]

Curious if anyone has gotten a forced OTA update to 5.7.2.

I have update.bin.tmp.partial folder on my Voyage 5.6.5. (per this post). I've had WiFi on, and so far no forced update. Don't know if it's because update.bin.tmp.partial is blocking it, or Amazon just hasn't gotten to my Voyage yet.

Anyway, I don't understand most of this developer stuff, so if there's any info I can provide that is useful to y'all, let me know.

[knc1]

Originally Posted by odamizu

Curious if anyone has gotten a forced OTA update to 5.7.2.

I have update.bin.tmp.partial folder on my Voyage 5.6.5. (per this post). I've had WiFi on, and so far no forced update. Don't know if it's because update.bin.tmp.partial is blocking it, or Amazon just hasn't gotten to my Voyage yet.

Anyway, I don't understand most of this developer stuff, so if there's any info I can provide that is useful to y'all, let me know.

That is the only way to test it -
Put the folder in there and hold it up in the air, see if Amazon shoots it down.

See bottom of this post:
https://www.mobileread.com/forums/sho...96&postcount=2

[Puky70]

Hi,

why do not block updates with a big dummy file?

for example:

1 MB = 1048576 bytes

fsutil file create new f:\kindle_storage\blockupdates 1048576
so now create a dummy file that only 150 MB is left on the kindle storage.

So there is not enough space for downloading the ota file. I hope that is correct?

In my case 150 MB free space is enough for any books on the Kindle. Normally I delete the books after reading...

Kind regards

Puky70

[knc1]

Originally Posted by Puky70

Hi,

why do not block updates with a big dummy file?

for example:

1 MB = 1048576 bytes

fsutil file create new f:\kindle_storage\blockupdates 1048576
so now create a dummy file that only 150 MB is left on the kindle storage.

So there is not enough space for downloading the ota file. I hope that is correct?

In my case 150 MB free space is enough for any books on the Kindle. Normally I delete the books after reading...

Kind regards

Puky70

Because earlier firmwares could not handle -ENOSPC, instead the Kindle would 'brick'.

Your welcome to try it out for us and report back when /mnt/us fills up.

Without any context given, I guess you are talking about a Windows tool to block Win10 updates.

Note that MS has very little support of MSDOS file systems, and user storage is FAT-32.
With that in mind, it is likely that tool creates "sparse" files.
Only FAT-32 doesn't handle 'sparse' files (files with un-recorded holes in them).
If it did, you would only have to: truncate -s 2G bigfile (no special tools involved).

[Puky70]

@knc1,

so I have created a dummy file "block_update" with 2.8 GB. Now I have 145 MB space left on my Kindle Voyage. Wifi is on since 1 hour and nothing happens and no file will be created on storage; such as update.bin.tmp.partial.

Another szenario i.e. we will fill the storage with thousand of mobi files that only 150 MB space is left. Now an OTA update will arrive; in most case the update file is about 200 MB. Therefore there is no space to store it. I don't think the device will brick about ENOSPC.

Now i will let wifi on to see later, if an update file will fill the storage.
The device is on 5.6.5 jailbroken firmware.

Kindly regards

Puky70

[aceflor]

It takes weeks for Amazon to send the update everywhere to everyone. Are you going to leave your storage filled up and WiFi on for over a month ? To prove what exactly ?

[knc1]

An interesting experiment.
Going by a notice Amazon sent me, it may be as late as March 22 before all the devices have been OTA updated.

[knc1]

Originally Posted by aceflor

It takes weeks for Amazon to send the update everywhere to everyone. Are you going to leave your storage filled up and WiFi on for over a month ? To prove what exactly ?

To find out if running out of file space on user storage space will still brick the Kindle or if Amazon/Lab126 has fixed that problem.

This is a 'normal' line of inquiry -
From time-to-time, somebody has to be willing to sacrifice a Kindle to the greater good.

[Puky70]

o.k.

thx for infos ;-)

[aceflor]

Originally Posted by knc1

To find out if running out of file space on user storage space will still brick the Kindle or if Amazon/Lab126 has fixed that problem.

This is a 'normal' line of inquiry -
From time-to-time, somebody has to be willing to sacrifice a Kindle to the greater good.

I understand that, if we knew that the OTA will be distributed in the next 48h that would make sense. But as, at least experienced by me, it can take quite a while to get an OTA, well, you'd be without file space for quite a while. Just sayin'.

[sandman7920]

If running out of space doesn't brick Kindle, this might be interesting
dd if=/dev/zero of=/mnt/us/file_fs.img bs=2M count=1024
mkfs.vfat /mnt/us/file_fs.img
mount -oloop /mnt/us/file_fs.img /mnt/us/documents
But i am not sure what will happen during usb-export