Kindle Jailbreak in 2024

[hexhexhex]

Originally Posted by mergen3107

Nope. You get JB once on a firmware. Then if you get updated, you need to restore it. That’s why people try to prevent OTA so that JB won’t break.

That's what I thought; so I'm still confused how you "restore" a JB after upgrading from 5.16.2 to 5.16.3, without a public 5.16.3 JB.

bear with me, I haven´t had my daily coffee

[mergen3107]

Current JB has preventative mechanism to stay alive.

However, you can still kill it for good if you do two firmware updates in a row, or two factory resets in a row, or any combination of these two.

If by the end of these two operations you end up on 5.16.3 and above, game’s over (hntil next JB method releases)

[hexhexhex]

Originally Posted by mergen3107

Current JB has preventative mechanism to stay alive.

Ahhh there's magic coming from the JB itself! I'll look into it to try and figure it out. Thanks

[mergen3107]

The file you are looking for is called fixup. It lives in /var/local/system/ after JB

[j.p.s]

Originally Posted by hexhexhex

Maybe I'm coming from a baremetal perspective where DFU usually mean a total reflash of the postupdate active partition.

Kindles don't have factory reset (flash original firmware), they have plain reset, which resets all configurations to default, clears all the sqlite databases in /var, and erases all user data in /mnt/us, which is the partition exported over USB mass storage.

The essential effect of the jailbreak process is to get a community developer key into /etc/uks, which can only be done by exploiting some vulnerability. Over time, functionality was added to squirrel away the ability to restore the developer key during a restart (reboot) after a firmware update or a reset. If an update is followed by a reset without a restart, or vice versa, bye bye jailbreak.

The developer key is needed because only packages signed by a key in /etc/uks can be installed. Of course, once USBnetworking or a terminal emulator is installed, / can be mounted rw long enough to put anything you want anywhere you want.

[hexhexhex]

Originally Posted by mergen3107

The file you are looking for is called fixup. It lives in /var/local/system/ after JB

Thank you!

Originally Posted by j.p.s

Kindles don't have factory reset (flash original firmware), they have plain reset, which resets all configurations to default, clears all the sqlite databases in /var, and erases all user data in /mnt/us, which is the partition exported over USB mass storage.

The essential effect of the jailbreak process is to get a community developer key into /etc/uks, which can only be done by exploiting some vulnerability. Over time, functionality was added to squirrel away the ability to restore the developer key during a restart (reboot) after a firmware update or a reset. If an update is followed by a reset without a restart, or vice versa, bye bye jailbreak.

The developer key is needed because only packages signed by a key in /etc/uks can be installed. Of course, once USBnetworking or a terminal emulator is installed, / can be mounted rw long enough to put anything you want anywhere you want.

Thanks for the detailed explanation.