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Reverse Engineering iOS 18 Inactivity Reboot

(naehrdine.blogspot.com)
511 points moonsword | 2 comments | 17 Nov 24 21:50 UTC | HN request time: 0.441s | source
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thrdbndndn ◴[18 Nov 24 01:27 UTC] No.42168908[source]▶
Two questions:

1. surely unconditionally rebooting locked iPhones every 3 days would cause issues in certain legit use cases?

2. If I read the article correctly, it reboots to re-enter "Before First Unlock" state for security. Why can't it just go into this state without rebooting?

Bonus question: my Android phone would ask for my passcode (can't unlock with fingerprint or face) if it thinks it might be left unattended (a few hours without moving etc.), just like after rebooting. Is it different from "Before First Unlock" state? (I understand Android's "Before First Unlock" state could be fundamentally different from iPhone's to begin with).

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1. dwaite ◴[18 Nov 24 02:48 UTC] No.42169304[source]▶
> Why can't it just go into this state without rebooting?

Because the state of the phone isn't clean - there is information in RAM, including executing programs that will be sad if the disk volume their open files are stored on goes away.

If your goal is to get to the same secure state the phone is in when it first starts, why not just soft reboot?

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2. TimeBearingDown ◴[18 Nov 24 04:20 UTC] No.42169685[source]▶
this also clears out deeper OS rootkits if they could not achieve reboot persistence, which is not uncommon.