Undecimus: Stability issues with Cydia Substrate on iOS 12

Created on 17 Apr 2019 · 4Comments · Source: pwn20wndstuff/Undecimus

I am submitting this issue to provide details about the issues and working ways of reproducing them to make it easier for @saurik to fix them - If you have your own discoveries, reply to this issue with them.

Hooking securityd causes the entire system to freeze (Reproduce: Install unc0ver v3.0.0~b48 from the releases page, install TetherMe or any tweak that hooks securityd, restart securityd)
Substrate's bootstrap_look_up hook seems to not be working properly, kernel occasionally complains about it in the syslog (e.g. iPhone kernel(Sandbox)[0] <Error>: Sandbox: lockdownd(379) deny(1) mach-lookup cy:com.saurik.substrated)
Running ldrestart occasionally causes the device to freeze and reboot
Jetsam is able to kill substrated under low memory conditions (e.g. https://ghostbin.com/paste/x8ckw)
Running this command will almost certainly freeze and crash the entire system on iOS 12 /usr/libexec/substrate && launchctl unload /System/Library/LaunchDaemons/com.apple.backboardd.plist && ldrestart; launchctl load /System/Library/LaunchDaemons/com.apple.backboardd.plist

Source

pwn20wndstuff

👍8

All 4 comments

So what is the state of the progress/future of this issue since Saurik has left the scene, Pwn? I guess fixing these will solve the random reboots/kernel panic still present there with the latest u0.

soum91 on 26 Apr 2019

❤1 😕1

unc0ver jailbreak Beta 5 worked fine but with beta 6 & 7 I get this...... ERROR: unable to start cydia substrate.
Any help would be appreciated.

NickyDee on 14 Jul 2019

👀2

unc0ver 3.6.2+1
I have many iPhone 6S + iOS 12.4 (exp: Sock Puppet 3.0) in app testing production.

random system freeze (need force shutdown)
re-jailbreak: unable to start substrate
app stuck at launch screen, no responding
cannot reload daemons (sshd), even "killall" got killed after a few hours

Once reboot & jailbreak, everything back to normal and perfect.
I don't know how to reproduce. All problems appear in a sudden, just after a few hours after jailbreak.