iOS 14 CoreFoundation crash with EXC_BREAKPOINT

This really doesn't give us much to go off of other than NSNetServiceBrowser is being removed from the current run loop and is crashing your app for some reason. Is there any more info to go off of here?



Matt Eaton
DTS Engineering, CoreOS
meaton3@apple.com

I could see in firebase keys section it has "Expected typeID 46 (CFRunLoopSource) does not match actual typeID 61 (CFSocket)" for key "crashinfoentry_0"

I am facing a strange issue in my app with iOS 14 there is a
intermittent crash

Please post a full crash report. It’s hard to say what’s code on here based on this snippet. Use the text attachment button (<>) to avoid clogging up the timeline.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@apple.com"

Firebase mentions one of the keys in crash log as
Expected typeID 46 (CFRunLoopSource) does not match actual typeID 61 (CFSocket)

Here is the complete crash log

Code Block 
Crashed: com.apple.main-thread
EXC_BREAKPOINT 0x00000001901fe700
Crashed: com.apple.main-thread
0  CoreFoundation                 0x1901fe700 _CFAssertMismatchedTypeID + 112
1  CoreFoundation                 0x190107f0c CFRunLoopSourceRemoveFromRunLoop + 306
2  CFNetwork                      0x1907d0808 CFNetServiceBrowserStopSearch + 472
3  CoreFoundation                 0x19010b81c CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION + 28
4  CoreFoundation                 0x19010b718 CFRunLoopDoSource0 + 208
5  CoreFoundation                 0x19010aa28 CFRunLoopDoSources0 + 268
6  CoreFoundation                 0x190104d20 CFRunLoopRun + 824
7  CoreFoundation                 0x1901044bc CFRunLoopRunSpecific + 600
8  GraphicsServices               0x1a6b89820 GSEventRunModal + 164
9  UIKitCore                      0x192aa8734 -[UIApplication _run] + 1072
10 UIKitCore                      0x192aade10 UIApplicationMain + 168
11 AppTarget_Qa        		        0x104e73ed4 main + 41 (AppDelegate.swift:41)
12 libdyld.dylib                  0x18fdcbe60 start + 4
Thread 1
0  libsystem_kernel.dylib         0x1bc0b85bc workq_kernreturn + 8
1  libsystem_pthread.dylib        0x1d76e0954 _pthread_wqthread + 352
2  libsystem_pthread.dylib        0x1d76e777c start_wqthread + 8
com.apple.uikit.eventfetch-thread
0  libsystem_kernel.dylib         0x1bc093dd0 mach_msg_trap + 8
1  libsystem_kernel.dylib         0x1bc093184 mach_msg + 76
2  CoreFoundation                 0x19010acf8 CFRunLoopServiceMachPort + 380
3  CoreFoundation                 0x190104ea8 CFRunLoopRun + 1216
4  CoreFoundation                 0x1901044bc CFRunLoopRunSpecific + 600
5  Foundation                     0x191381e30 -[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 232
6  Foundation                     0x191381d08 -[NSRunLoop(NSRunLoop) runUntilDate:] + 92
7  UIKitCore                      0x192b58e94 -[UIEventFetcher threadMain] + 516
8  Foundation                     0x1914ec0f0 NSThreadstart + 864
9  libsystem_pthread.dylib        0x1d76deca8 _pthread_start + 320
10 libsystem_pthread.dylib        0x1d76e7788 thread_start + 8
AVAudioSession Notify Thread
0  libsystem_kernel.dylib         0x1bc093dd0 mach_msg_trap + 8
1  libsystem_kernel.dylib         0x1bc093184 mach_msg + 76
2  CoreFoundation                 0x19010acf8 CFRunLoopServiceMachPort + 380
3  CoreFoundation                 0x190104ea8 CFRunLoopRun + 1216
4  CoreFoundation                 0x1901044bc CFRunLoopRunSpecific + 600
5  AudioSession                   0x1979a62ac GenericRunLoopThread::Entry(void*) + 164
6  AudioSession                   0x1979a8390 CAPThread::Entry(CAPThread*) + 92
7  libsystem_pthread.dylib        0x1d76deca8 _pthread_start + 320
8  libsystem_pthread.dylib        0x1d76e7788 thread_start + 8
com.google.firebase.crashlytics.MachExceptionServer
0  AppTarget_Qa        		        0x10510a9b4 FIRCLSProcessRecordAllThreads + 392 (FIRCLSProcess.c:392)
1  AppTarget_Qa		                0x10510ad98 FIRCLSProcessRecordAllThreads + 423 (FIRCLSProcess.c:423)
2  AppTarget_Qa 	                0x105101624 FIRCLSHandler + 34 (FIRCLSHandler.m:34)
3  AppTarget_Qa		                0x105104054 FIRCLSMachExceptionServer + 524 (FIRCLSMachException.c:524)
4  libsystem_pthread.dylib        0x1d76deca8 _pthread_start + 320
5  libsystem_pthread.dylib        0x1d76e7788 thread_start + 8
Thread 2
0  libsystem_kernel.dylib         0x1bc0b85bc workq_kernreturn + 8
1  libsystem_pthread.dylib        0x1d76e0954 _pthread_wqthread + 352
2  libsystem_pthread.dylib        0x1d76e777c start_wqthread + 8
com.apple.NSURLConnectionLoader
0  libsystem_kernel.dylib         0x1bc093dd0 mach_msg_trap + 8
1  libsystem_kernel.dylib         0x1bc093184 mach_msg + 76
2  CoreFoundation                 0x19010acf8 CFRunLoopServiceMachPort + 380
3  CoreFoundation                 0x190104ea8 CFRunLoopRun + 1216
4  CoreFoundation                 0x1901044bc CFRunLoopRunSpecific + 600
5  CFNetwork                      0x1909bd050 _CFURLStorageSessionCopyCache + 63240
6  Foundation                     0x1914ec0f0 NSThreadstart + 864
7  libsystem_pthread.dylib        0x1d76deca8 _pthread_start + 320
8  libsystem_pthread.dylib        0x1d76e7788 thread_start + 8
com.apple.CFSocket.private
0  libsystem_kernel.dylib         0x1bc0b7c40 select + 8
1  libsystem_kernel.dylib         0x1bc0b7c40 select$DARWIN_EXTSN + 8
2  CoreFoundation                 0x190117688 CFSocketManager + 636
3  libsystem_pthread.dylib        0x1d76deca8 _pthread_start + 320
4  libsystem_pthread.dylib        0x1d76e7788 thread_start + 8
Thread 3
0  libsystem_kernel.dylib         0x1bc0b85bc workq_kernreturn + 8
1  libsystem_pthread.dylib        0x1d76e0954 _pthread_wqthread + 352
2  libsystem_pthread.dylib        0x1d76e777c start_wqthread + 8
Thread 4
0  libsystem_kernel.dylib         0x1bc0b85bc workq_kernreturn + 8
1  libsystem_pthread.dylib        0x1d76e0954 _pthread_wqthread + 352
2  libsystem_pthread.dylib        0x1d76e777c start_wqthread + 8
Thread 5
0  libsystem_kernel.dylib         0x1bc0b85bc __workq_kernreturn + 8
1  libsystem_pthread.dylib        0x1d76e0954 _pthread_wqthread + 352
2  libsystem_pthread.dylib        0x1d76e777c start_wqthread + 8

Here is the complete crash log

OK, sorry, I was looking for a complete Apple crash report. I presume this is from a third-party crash reporter? If so, there’s not much I can do with it )-:

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@apple.com"

We are facing a similar, intermittent crash, observed in both simulator and real devices. The app is running NISession over MCSession based on the NIPeekaboo sample from WWDC. The crash occurs when the peer exits the session. We've observed it when the peer exits gracefully, using NISession.invalidate(), and when it exits abruptly due to the app being closed.

Simulator crash report attached. I can provide a device crash report with similar signature if that would help.

I can provide a device crash report with similar signature if that
would help.

Yes please!

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@apple.com"

Here it is!

This is a bit tricky because something (probably some serious inlining) is messing up the symbolication. Consider the top few frames of the crashing thread

Code Block  
0 CoreFoundation … _CFAssertMismatchedTypeID + 112 (CFRuntime.c:934)
1 CoreFoundation … _CFAssertMismatchedTypeID + 104 (CFRuntime.c:933)
2 CoreFoundation … CFRunLoopSourceInvalidate + 308 (CFRuntime_Internal.h:118)
3 CFNetwork      … _BrowserCancel(__CFNetServiceBrowser*) + 80 (CFNetServiceBrowser.c:178)

It makes sense that _BrowserCancel(…) (frame 3) would call CFRunLoopSourceInvalidate (frame 2) but the source line for that frame is kinda bogus. In reality, CFRuntime_Internal.h:118 points to a CF type checking macro. So, while we know you’ve crashed due to a runtime type check, it’s not clear exactly which type that is.

Having said that, the Application Specific Information section in the simulator crash report is helpful:

Code Block  
Expected typeID 46 (CFRunLoopSource) does not match actual typeID 61 (CFSocket)
CoreSimulator 732.18 - Device: iPhone 12 Pro Max (D40711DE-CECD-41C7-BE1B-4222E3CF24BD) - Runtime: iOS 14.1 (18A8394) - DeviceType: iPhone 12 Pro Max

This suggests that the type check you’re hitting is the one early in the CFRunLoopSourceInvalidate, where it checks that the parameter you pass in is action a run loop source.

Of course it’s a complete mystery why the browser would be calling CFRunLoopSourceInvalidate with a socket. Looking at the code it’s hard to imagine how that’d could ever happen. My best guess is that you have some sort of memory management problem. I recommend that you run with the standard memory debugging tools to see if that causes the problem to become more reproducible.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@apple.com"

I've checked all the memory debugging boxes. At the Xcode breakpoint, I see references to NSCalendar and locale operations, which don't appear in the crash reports.

Good news?! I've reproduced the crash using the NIPeekaboo sample from WWDC. Running on two NI capable devices:

• Accept the permission on both devices so NISession can be established

• Restart the app on device A (e.g. by relaunching from Xcode)

• The app will reliably crash on device B

Crash signature is the same as we've seen with our own app.

Good news?! I've reproduced the crash using the NIPeekaboo sample from
WWDC.

That is indeed good news. As this point we know it’s not your code because you’re not running any of your code. I’d appreciate you filing a bug about this. Please post your bug number, just for the record.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@apple.com"

FB8891415 (Application crash on peer reconnect using MultiPeer Connectivity to facilitate a Nearby Interaction session)

FB8891415

Thanks for that.

There’s some suggestion that this was fixed in one of the 14.x software updates. Please re-run your steps to reproduce on the latest 14.3 beta and let us know how you get along.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@apple.com"

We've been seeing a number of crashes with a similar assertion, but related to the EAAccessory Framework. I'm attaching one of these crash logs in hopes someone has suggestions for how I'd debug this further. Unfortunately, much of the EAAccessory related code in our app comes from a number of closed-source third party SDKs.

We've been seeing a number of crashes with a similar assertion, but
related to the EAAccessory Framework.

These errors are unlikely to be related. You’re crashing for the same reason (CF has detected a type mismatch at runtime) but the cause of that type mismatch is very different.

Consider this snippet from the crashing thread’s backtrace:

Code Block  
1   CoreFoundation    … _CFAssertMismatchedTypeID + 100
2   CoreFoundation    … CFRunLoopSourceSignal + 312
3   ExternalAccessory … -[EAInputStream _scheduleCallback] + 72
4   ExternalAccessory … -[EAInputStream _performAtEndOfStreamValidation] + 116

Frame 1 is the type mismatch, but note how frames 2 is different (in the other cases it was removing a run loop source) as are frames 3 and 4.

I recommend that you open a new thread for this and tag it with ExternalAccessory to see if anyone with EA experience (which I do not have, btw) chimes in.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@apple.com"

Hello there,

Has anyone figured out the cause of this crash?
We are facing the same issue since iOS 14 (14.3 and 14.4) when using multipeer connectivity and MCNearbyServiceBrowser.

Thanks!

Our app uses Multipeer Connectivity and we've been experiencing this issue since iOS 14 was released.

One common theme is that the app is running in the background when the issue arrises and we get the crash.

Expected typeID 46 (CFRunLoopSource) does not match actual typeID 61 (CFSocket)

We've been trying to diagnose what is happening through our remote logging, but so far the cause of the issue has escaped us.

One common theme is that the app is running in the background when the
issue arrises and we get the crash.

You use Multipeer Connectivity in the background? Is that just because you don’t shut it down when you move to the background? Or because you actually need to use it in the background?

Multipeer Connectivity isn’t rated for use the background. Some parts of it will likely work as long as you guarantee that your process never gets suspended (as is generally true for out networking APIs). Other parts simply don’t make sense in the background.

Having said that, it shouldn’t crash )-:

Do you have an Apple crash report for this? If so, please post it here. Use the text attachment feature (the paperclip icon) to avoid clogging up the timeline.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Hi,

Would this Apple crash report help?

Thanks,

Would this Apple crash report help?

Yes, and no.

It’s clearly the same issue and it helped me track down the bug we’re using to track this (r. 60399638). However, that bug doesn’t offer any suggestions for how you might work around it.

Two factoids of note:

• We’re seeing this reported by a number of different apps, suggesting that this is a bug in the system rather than a bug in the apps.

• It’s likely that immediate cause of this crash was a change we made in iOS 14 to harden CF-level APIs against type mismatches (r. 14049993). So, this problem may have been occurring previously but iOS 14 is now detecting it reliably.

Oh, one other thing: It’s clear that this bug is triggered by a CF-level problem. That means it affects CFNetServiceBrowser and all the things layered on top of that, including NSNetServiceBrowser and Multipeer Connectivity. If you move to a different Bonjour API, one not based on CFNetServiceBrowser, it’s likely that you wouldn’t see this problem. That includes NWBrowser and the very low-level DNS-SD API (<dns_sd.h>). Of those, I’m going to recommend NWBrowser; Network framework is the future of (non-HTTP) networking on our platforms.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

So has this bug been fixed?

Our current thinking is that the bug mentioned above (r. 60399638) is specific to Multipeer Connectivity. Are you using that API? Or some other Bonjour API?

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Is there any update to the status of this bug (r. 60399638)?

No.

Are there any workarounds

As I said in my previous post, our current thinking is that this is specific to Multipeer Connectivity, and thus the ‘obvious’ workaround is to use a different API for your networking. My general recommendation is Network framework but if you want to talk specifics I encourage you to start a new thread with details about your network architecture.

an estimated timeline for a fix?

I can’t predict the future, alas. I will, however, note this problem started in iOS 14 and hasn’t been fixed in iOS 15, and let you draw your own conclusions.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

We are facing a similar, intermittent crash, observed in iPad Pro (12.9-inch, 3rd generation) Version:17.2.0 real devices

Fatal Exception: NSInternalInconsistencyException 0 CoreFoundation 0xf2564 (Missing UUID 47e4ec098f6e30a899d034024d4f8122) 1 libobjc.A.dylib 0x19eb4 (Missing UUID 9bab95567a2a30a8acde010ba8e2367d) 2 Foundation 0x82940 (Missing UUID 9558b1ebdda33fda88a5e785ecdfcd30) 3 Foundation 0xe0ee0 (Missing UUID 9558b1ebdda33fda88a5e785ecdfcd30) 4 Foundation 0x75af30 (Missing UUID 9558b1ebdda33fda88a5e785ecdfcd30) 5 AppKit 0x7cbf8 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 6 AppKit 0xad154c (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 7 AppKit 0x31e5b4 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 8 AppKit 0x33e1c0 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 9 AppKit 0xde1a74 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 10 AppKit 0x347e4 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 11 AppKit 0xde159c (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 12 AppKit 0xde0f54 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 13 AppKit 0xde112c (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 14 AppKit 0x7a695c (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 15 AppKit 0x7a6ce4 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 16 SkyLight 0xb134 (Missing UUID 67c718b452dc3b258e7a12ea2b414369) 17 SkyLight 0x3a0230 (Missing UUID 67c718b452dc3b258e7a12ea2b414369) 18 SkyLight 0x3a012c (Missing UUID 67c718b452dc3b258e7a12ea2b414369) 19 libdispatch.dylib 0x1cb8 (Missing UUID a53d555df748301083fe385c660a81bd) 20 libdispatch.dylib 0x3910 (Missing UUID a53d555df748301083fe385c660a81bd) 21 libdispatch.dylib 0x11fa8 (Missing UUID a53d555df748301083fe385c660a81bd) 22 libdispatch.dylib 0x11bc0 (Missing UUID a53d555df748301083fe385c660a81bd) 23 CoreFoundation 0xbeecc (Missing UUID 47e4ec098f6e30a899d034024d4f8122) 24 CoreFoundation 0x7c7d0 (Missing UUID 47e4ec098f6e30a899d034024d4f8122) 25 CoreFoundation 0x7b9ac (Missing UUID 47e4ec098f6e30a899d034024d4f8122) 26 HIToolbox 0x30448 (Missing UUID e2187dfe1fb43b47874ea0a6291e51b2) 27 HIToolbox 0x30284 (Missing UUID e2187dfe1fb43b47874ea0a6291e51b2) 28 HIToolbox 0x2ffdc (Missing UUID e2187dfe1fb43b47874ea0a6291e51b2) 29 AppKit 0x398a4 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 30 AppKit 0x813980 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 31 AppKit 0x2cd50 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 32 AppKit 0x4014 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 33 AppKit 0x2573a4 (Missing UUID f3527312e4263f7cb77b2bf49d1b7c04) 34 UIKitMacHelper 0x46a8 (Missing UUID f03f3f95a13739e2b894c76dc6e8a1e5) 35 UIKitCore 0x3cfc (Missing UUID 2aebcc42a1aa3535be531da03d4d2ce3) 36 Enlighten 0x70e8 main + 32 (main.m:32) 37 ??? 0x183ef50e0 (Missing)

Any updates on this crash / fix / rdar? We are also seeing this crash. Even when the app is in foreground. It happens randomly. Hard to reproduce.