Disabling iOS Personalized Ads tells kernel to kill daemon every 3 seconds

https://twitter.com/whitetailani/status/1727576164284129654?s=20

by nethuml • 3 years ago

154 50 3 years ago

twitter.com

engcoach• 3 years ago

That’s called a bug, bro

vorticalbox• 3 years ago

I agree I would be shocked if this were intended behaviour

whatsthatabout• 3 years ago

That was my thought as well. Hope this get fixed in one of the next releases and someone compares battery life.

pimlottc• 3 years ago

Note: It may work differently on later iOS - I tested on 15.4.1

That's over a year and a half (released Mar 2022) and two major revisions ago, would be helpful to confirm if this is still an issue.

freetime2• 3 years ago

Yup and as others have noted, this report comes from a jailbroken iPhone. I have nothing against people jailbreaking their phones, but it would be good to know if this issue also occurs on iPhones running up-to-date stock iOS.

meitros• 3 years ago

Is it every three seconds? Or every time a process is run, kill the daemon within 3 seconds? Or even, only if the daemon spawns kill it within 3 seconds. The latter two wouldn't be nearly as impactful as the first, and the sandbox message didn't seem clear enough for me to tell.

saagarjha2• 3 years ago

It’s very possible that iOS can end up in a situation where it starts starting a daemon in a loop but the premise here seems a little unexplored to me given the odd nature of the bug. The kernel failing to spawn the process due to a sandbox issue seems very odd. Given that the device is obviously jailbroken I think it’s somewhat likely that a sloppy patch or tweak is causing this to occur instead.

osy• 3 years ago

The screenshot is (obviously) from a jailbroken phone. Currently nobody with a stock phone can reproduce it (through Console on a Mac with Developer Mode enabled) although you are free to try it and test for yourself. This is just another side effect of how jailbreaks make your device more unstable.

dylan604• 3 years ago

Sorry, for those of us that are not mobile devs, how are the white text on black background obviously signaling that it is jailbroken?

saagarjha2• 3 years ago

The console message is from an app for jailbroken devices: https://github.com/NSAntoine/Antoine

shinratdr• 3 years ago

You wouldn’t be able to see that debug information on the phone itself if it wasn’t jailbroken, as the GP mentioned you would need to use console on a Mac. The second screenshot is from a phone, ergo, jailbreak.

Also other commenters have mentioned he’s on 15.4.1. That’s two major iOS versions old. It’s possible they’re just on an iPhone 6S/SE/7 which was capped at that version, but a jailbreak is likely.

whywhywhywhy2• 3 years ago

Isn't something deeply broken if that would cause issues with something as superfluous as ad tracking?

vore2• 3 years ago

I feel like all bets are off if you're modifying your phone away from what the manufacturer explicitly supports. Not saying you shouldn't, but this says nothing about the brokenness of the stock software.

EPWN3D• 3 years ago

No.

slantedview• 3 years ago

Does jailbreaking somehow cause Apple ad tracking to run as a daemon? Maybe you can explain how these things are possibly related.

TheCleric• 3 years ago

My guess? The ad tracking is a daemon regardless, but when you disable it regularly it disables the daemon. However when jailbroken, there may be code within the jailbreak or an assumption within the OS code that has two processes fighting over starting it and stopping it.

For example the jailbroken code might have something that tries to keep all daemons running and the OS sees the ad one running and tries to kill it.

nottorp2• 3 years ago

Apple is pretty good at having daemons that randomly take 100% cpu with no recourse. Last one didn't have access to something I didn't know existed, and it was Apple who should have set it up :)

Narishma• 3 years ago

Microsoft is very good at it too.

ryandrake• 3 years ago

It’s a problem that spans across all modern operating systems. Even if they are not taking up 100% CPU, they are running and that’s still a problem. Just look at Windows Task Manager or Apple’s Activity Monitor (or even Linux ps on some problematic distributions). There are always dozens (hundreds?) of unknown daemons sitting there doing god knows what on a computer that is supposed to be yours. How did we users allow this to happen?

I long for the days when all that was running on your computer were things you commanded it to run, not things that the OS vendor wants running at all times for whatever (nefarious or otherwise) purpose.

musicale4• 3 years ago

Apple is pretty good at having daemons that randomly take 100% cpu with no recourse

Spotlight/mds/mdworker/... has been a monstrosity since forever, but the accursed macOS daemons that earn my unending ire are photoanalysisd and syspolicyd. (The former probably runs on iOS as well but I mitigate it by deleting photos after import.)

Whenever I pull my laptop out of a bag or backpack and it's unreasonably hot, photoanalysisd or syspolicyd are usually to blame, scanning the same files again for the 1000th time. I haven't enabled smart nap, so this must be the "stupid nap" functionality.

There doesn't seem to be any easy way to disable these evil daemons without messing with SIP etc. Even if you disable awful misfeatures of Photos like Memories, photoanalysisd still runs. Syspolicyd doesn't have a UI. At least with spotlight you can disable it on certain volumes, though of course that breaks Mail's search function.

Regarding 100% CPU, I wonder if low-power mode would help? iOS low-power mode seems like a great feature, but unfortunately it turns itself back on after the battery charges.

graphe• 3 years ago

I jailbreak and photoanalysisd always fails or causes high CPU usage on iOS.

seec• 3 years ago

Yeah I wish they would stop the bullshit with their photo software. We had iPhoto, it was fine, it had almost all the features you could want for a nonprofessional photo cataloging software. But they had to overengineer a new one full of unnecessary features and useless daemon.

Funniest thing is that ease of access/availability of photos in other apps hasn't improved much so what's the point of the overkill photo DB. Better use the filesystem at this point...

netsharc• 3 years ago

If I were a conspiracy nutter I'd ponder the daemon name and Apple's plan to scan for child porn.

In the 2000's, Windows Explorer on Windows XP had a feature to preview media files, but when it encounters a large video the system doesn't have a codec for...

grishka• 3 years ago

What makes the daemon start in the first place? If it's a launchd service, which I assume it is, why do they not disable it instead?

j16sdiz• 3 years ago

No, it's unrelated.

https://github.com/WebKit/WebKit/commit/064df1a9f395f8c6e32c...

xcdzvyn• 3 years ago

So this post is about a bug from two years ago that's completely unrelated to the purported cause?

max_• 3 years ago

How did he detect this, what tool is he using to view daemons?

mh-• 3 years ago

He's on a jailbroken device running an older iOS version.

TriangleEdge• 3 years ago

I find these "short term" permanent fixes funny. It's hard for me to conceive of the reasoning that lead to this. My guess is the Ads team at Apple must be super locked down, and an outsider must of had to implement the solution without interaction with that team I suppose.

lern_too_spel• 3 years ago

Nitter: https://nitter.net/whitetailani/status/1727576164284129654

steponlego• 3 years ago

Did everybody who knows about Unix leave Apple like, I don't know, around the 10.5-10.6 days? It certainly seems that way to me.

Disabling iOS Personalized Ads tells kernel to kill daemon every 3 seconds

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