Disconnects and crashes with Could not create epoll instance: Too many open files

[sersorrel]

Since updating to Android 13, DNS66 has sometimes started randomly disconnecting, with the notification saying "Reconnecting error". If I open the app while in this state, it crashes, with the following in logcat:

08-31 12:23:04.578 17247 17247 D wpa_supplicant: nl80211: Ignore unsupported QCA vendor event 13
08-31 12:23:04.842 28695 28695 F DEBUG   : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
08-31 12:23:04.842 28695 28695 F DEBUG   : Build fingerprint: 'google/sunfish/sunfish:13/TP1A.220624.014/8819323:user/release-keys'
08-31 12:23:04.842 28695 28695 F DEBUG   : Revision: 'MP1.0'
08-31 12:23:04.842 28695 28695 F DEBUG   : ABI: 'arm64'
08-31 12:23:04.842 28695 28695 F DEBUG   : Timestamp: 2022-08-31 12:23:04.359280848+0100
08-31 12:23:04.842 28695 28695 F DEBUG   : Process uptime: 1483s
08-31 12:23:04.842 28695 28695 F DEBUG   : Cmdline: org.jak_linux.dns66
08-31 12:23:04.842 28695 28695 F DEBUG   : pid: 24804, tid: 24804, name: jak_linux.dns66  >>> org.jak_linux.dns66 <<<
08-31 12:23:04.842 28695 28695 F DEBUG   : uid: 10266
08-31 12:23:04.842 28695 28695 F DEBUG   : signal 6 (SIGABRT), code -1 (SI_QUEUE), fault addr --------
08-31 12:23:04.842 28695 28695 F DEBUG   : Abort message: 'Could not create epoll instance: Too many open files'
08-31 12:23:04.842 28695 28695 F DEBUG   :     x0  0000000000000000  x1  00000000000060e4  x2  0000000000000006  x3  0000007fd77cced0
08-31 12:23:04.842 28695 28695 F DEBUG   :     x4  6e42721f21213c6f  x5  6e42721f21213c6f  x6  6e42721f21213c6f  x7  7f7f7f7f7f7f7f7f
08-31 12:23:04.842 28695 28695 F DEBUG   :     x8  00000000000000f0  x9  00000075718e7a00  x10 0000000000000001  x11 0000007571925ce4
08-31 12:23:04.842 28695 28695 F DEBUG   :     x12 0000000000001401  x13 000000000000065c  x14 0000007fd77cbcf0  x15 0000000004ce108a
08-31 12:23:04.842 28695 28695 F DEBUG   :     x16 000000757198ad60  x17 0000007571967b70  x18 0000007584686000  x19 00000000000060e4
08-31 12:23:04.842 28695 28695 F DEBUG   :     x20 00000000000060e4  x21 00000000ffffffff  x22 00000072c6a15000  x23 00000072c6a16000
08-31 12:23:04.842 28695 28695 F DEBUG   :     x24 0000007583a8e000  x25 0000000012c86dd0  x26 0000000014b03d50  x27 00000000141c0000
08-31 12:23:04.842 28695 28695 F DEBUG   :     x28 0000000000000000  x29 0000007fd77ccf50
08-31 12:23:04.842 28695 28695 F DEBUG   :     lr  0000007571917868  sp  0000007fd77cceb0  pc  0000007571917894  pst 0000000000000000
08-31 12:23:04.842 28695 28695 F DEBUG   : backtrace:
08-31 12:23:04.842 28695 28695 F DEBUG   :       #00 pc 0000000000051894  /apex/com.android.runtime/lib64/bionic/libc.so (abort+164) (BuildId: 058e3ec96fa600fb840a6a6956c6b64e)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #01 pc 00000000006d29ec  /apex/com.android.art/lib64/libart.so (art::Runtime::Abort(char const*)+704) (BuildId: 56e704c544e6c624201be2ab4933e853)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #02 pc 0000000000016ea8  /apex/com.android.art/lib64/libbase.so (android::base::SetAborter(std::__1::function<void (char const*)>&&)::$_3::__invoke(char const*)+80) (BuildId: b77c57f68a484ed93d5a7eda59d83bf9)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #03 pc 0000000000009de0  /system/lib64/liblog.so (__android_log_assert+292) (BuildId: 1f951eeceedbbe038f287e24d36cbd34)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #04 pc 0000000000014340  /system/lib64/libutils.so (android::Looper::rebuildEpollLocked()+628) (BuildId: 5a0d720732600c94ad8354a1188e9f52)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #05 pc 0000000000014060  /system/lib64/libutils.so (android::Looper::Looper(bool)+284) (BuildId: 5a0d720732600c94ad8354a1188e9f52)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #06 pc 000000000023b6a4  /system/lib64/libhwui.so (android::uirenderer::ThreadBase::ThreadBase()+72) (BuildId: 835cbecd6a5144b64a65f846b2b85d67)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #07 pc 0000000000504a74  /system/lib64/libhwui.so (android::uirenderer::renderthread::RenderThread::getInstance()+120) (BuildId: 835cbecd6a5144b64a65f846b2b85d67)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #08 pc 0000000000511e24  /system/lib64/libhwui.so (android::uirenderer::renderthread::RenderProxy::preload()+28) (BuildId: 835cbecd6a5144b64a65f846b2b85d67)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #09 pc 00000000002cba80  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (art_jni_trampoline+112)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #10 pc 00000000007bf08c  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.app.ActivityThread.handleLaunchActivity+1148)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #11 pc 00000000009a76f4  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.app.servertransaction.LaunchActivityItem.execute+484)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #12 pc 00000000006e953c  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.app.servertransaction.TransactionExecutor.executeCallbacks+588)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #13 pc 00000000006e9268  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.app.servertransaction.TransactionExecutor.execute+808)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #14 pc 000000000079af44  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.app.ActivityThread$H.handleMessage+1204)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #15 pc 0000000000a17920  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.os.Handler.dispatchMessage+192)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #16 pc 0000000000a1b968  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.os.Looper.loopOnce+1032)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #17 pc 0000000000a1b42c  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.os.Looper.loop+1148)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #18 pc 00000000007b4814  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (android.app.ActivityThread.main+1364)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #19 pc 0000000000436e00  /apex/com.android.art/lib64/libart.so (art_quick_invoke_static_stub+576) (BuildId: 56e704c544e6c624201be2ab4933e853)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #20 pc 0000000000469534  /apex/com.android.art/lib64/libart.so (_jobject* art::InvokeMethod<(art::PointerSize)8>(art::ScopedObjectAccessAlreadyRunnable const&, _jobject*, _jobject*, _jobject*, unsigned long)+1960) (BuildId:56e704c544e6c624201be2ab4933e853)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #21 pc 0000000000468d64  /apex/com.android.art/lib64/libart.so (art::Method_invoke(_JNIEnv*, _jobject*, _jobject*, _jobjectArray*) (.__uniq.165753521025965369065708152063621506277)+48) (BuildId: 56e704c544e6c624201be2ab4933e853)
08-31 12:23:04.842 28695 28695 F DEBUG   :       #22 pc 00000000002d1148  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (art_jni_trampoline+120)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #23 pc 0000000000d3fd60  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run+144)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #24 pc 0000000000d4ab08  /data/misc/apexdata/com.android.art/dalvik-cache/arm64/boot.oat (com.android.internal.os.ZygoteInit.main+3464)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #25 pc 0000000000436e00  /apex/com.android.art/lib64/libart.so (art_quick_invoke_static_stub+576) (BuildId: 56e704c544e6c624201be2ab4933e853)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #26 pc 0000000000582e28  /apex/com.android.art/lib64/libart.so (art::JValue art::InvokeWithVarArgs<_jmethodID*>(art::ScopedObjectAccessAlreadyRunnable const&, _jobject*, _jmethodID*, std::__va_list)+900) (BuildId: 56e704c544e6c624201be2ab4933e853)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #27 pc 00000000005f5f48  /apex/com.android.art/lib64/libart.so (art::JNI<true>::CallStaticVoidMethodV(_JNIEnv*, _jclass*, _jmethodID*, std::__va_list)+160) (BuildId: 56e704c544e6c624201be2ab4933e853)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #28 pc 00000000000bcad0  /system/lib64/libandroid_runtime.so (_JNIEnv::CallStaticVoidMethod(_jclass*, _jmethodID*, ...)+120) (BuildId: 652257cd0faef901accde2659193d1c3)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #29 pc 00000000000c85c4  /system/lib64/libandroid_runtime.so (android::AndroidRuntime::start(char const*, android::Vector<android::String8> const&, bool)+840) (BuildId: 652257cd0faef901accde2659193d1c3)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #30 pc 0000000000002554  /system/bin/app_process64 (main+1280) (BuildId: a1ab812b262121cb66f7cbe228dc9674)
08-31 12:23:04.843 28695 28695 F DEBUG   :       #31 pc 000000000004a0f4  /apex/com.android.runtime/lib64/bionic/libc.so (__libc_init+96) (BuildId: 058e3ec96fa600fb840a6a6956c6b64e)
08-31 12:23:04.917  1096  1217 D CHRE    : @ 341771.183: [ActivityPlatform] type 6, confidence 41
08-31 12:23:04.917  1096  1217 I CHRE    : @ 341771.183: [cc] onArResult activity=5, conf=421
08-31 12:23:04.926  1793 28699 I DropBoxManagerService: add tag=data_app_native_crash isTagEnabled=true flags=0x2
08-31 12:23:04.926   890   890 E tombstoned: Tombstone written to: tombstone_14
08-31 12:23:04.927  1793 28698 W ActivityTaskManager:   Force finishing activity org.jak_linux.dns66/.MainActivity
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: failed to open /data/tombstones/tombstone_14.pb
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: java.io.FileNotFoundException: open failed: ENOENT (No such file or directory)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at android.os.ParcelFileDescriptor.openInternal(ParcelFileDescriptor.java:342)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at android.os.ParcelFileDescriptor.open(ParcelFileDescriptor.java:229)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at com.android.server.os.NativeTombstoneManager.handleProtoTombstone(NativeTombstoneManager.java:151)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at com.android.server.os.NativeTombstoneManager.handleTombstone(NativeTombstoneManager.java:120)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at com.android.server.os.NativeTombstoneManager.-$$Nest$mhandleTombstone(Unknown Source:0)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at com.android.server.os.NativeTombstoneManager$TombstoneWatcher.lambda$onEvent$0(NativeTombstoneManager.java:564)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at com.android.server.os.NativeTombstoneManager$TombstoneWatcher.$r8$lambda$brzM_6e7cyhhJeR_ISUCuvFg3_s(Unknown Source:0)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at com.android.server.os.NativeTombstoneManager$TombstoneWatcher$$ExternalSyntheticLambda0.run(Unknown Source:4)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at android.os.Handler.handleCallback(Handler.java:942)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at android.os.Handler.dispatchMessage(Handler.java:99)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at android.os.Looper.loopOnce(Looper.java:201)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at android.os.Looper.loop(Looper.java:288)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at android.os.HandlerThread.run(HandlerThread.java:67)
08-31 12:23:04.928  1793  2330 W NativeTombstoneManager: 	at com.android.server.ServiceThread.run(ServiceThread.java:44)
08-31 12:23:04.938  1793  2330 I BootReceiver: Copying /data/tombstones/tombstone_14 to DropBox (SYSTEM_TOMBSTONE)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: Exception thrown during pause
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: android.os.DeadObjectException
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at android.os.BinderProxy.transactNative(Native Method)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at android.os.BinderProxy.transact(BinderProxy.java:584)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at android.app.IApplicationThread$Stub$Proxy.scheduleTransaction(IApplicationThread.java:1900)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at android.app.servertransaction.ClientTransaction.schedule(ClientTransaction.java:136)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.ClientLifecycleManager.scheduleTransaction(ClientLifecycleManager.java:47)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.ClientLifecycleManager.scheduleTransaction(ClientLifecycleManager.java:69)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.TaskFragment.schedulePauseActivity(TaskFragment.java:1665)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.TaskFragment.startPausing(TaskFragment.java:1608)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.ActivityRecord.finishIfPossible(ActivityRecord.java:3431)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.ActivityRecord.finishIfPossible(ActivityRecord.java:3321)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.Task.finishTopCrashedActivityLocked(Task.java:5270)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.RootWindowContainer.lambda$finishTopCrashedActivities$17(RootWindowContainer.java:2232)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.RootWindowContainer.$r8$lambda$tU3uq54E6s47P2cFrn4v86Si-94(Unknown Source:0)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.RootWindowContainer$$ExternalSyntheticLambda43.accept(Unknown Source:10)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.Task.forAllTasks(Task.java:3166)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.WindowContainer.forAllTasks(WindowContainer.java:1944)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.WindowContainer.forAllTasks(WindowContainer.java:1944)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.WindowContainer.forAllTasks(WindowContainer.java:1944)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.WindowContainer.forAllTasks(WindowContainer.java:1944)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.WindowContainer.forAllTasks(WindowContainer.java:1944)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.WindowContainer.forAllTasks(WindowContainer.java:1944)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.WindowContainer.forAllTasks(WindowContainer.java:1944)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.WindowContainer.forAllTasks(WindowContainer.java:1937)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.RootWindowContainer.finishTopCrashedActivities(RootWindowContainer.java:2231)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.wm.ActivityTaskManagerService$LocalService.finishTopCrashedActivities(ActivityTaskManagerService.java:6414)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.am.AppErrors.handleAppCrashLSPB(AppErrors.java:934)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.am.AppErrors.makeAppCrashingLocked(AppErrors.java:766)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.am.AppErrors.crashApplicationInner(AppErrors.java:641)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.am.AppErrors.crashApplication(AppErrors.java:569)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.am.ActivityManagerService.handleApplicationCrashInner(ActivityManagerService.java:8483)
08-31 12:23:04.941  1793 28698 W ActivityTaskManager: 	at com.android.server.am.NativeCrashListener$NativeCrashReporter.run(NativeCrashListener.java:88)
08-31 12:23:04.951 30122 30146 D QuickstepModelDelegate: notifyAppTargetEvent action=1 launchLocation=
08-31 12:23:04.952  1793  2043 I ActivityManager: Showing crash dialog for package org.jak_linux.dns66 u0
08-31 12:23:04.953  1793  2330 I DropBoxManagerService: add tag=SYSTEM_TOMBSTONE isTagEnabled=true flags=0x6
08-31 12:23:04.962  1793  2069 W BroadcastQueue: Background execution not allowed: receiving Intent { act=android.intent.action.DROPBOX_ENTRY_ADDED flg=0x10 (has extras) } to com.google.android.gms/.stats.service.DropBoxEntryAddedReceiver
08-31 12:23:04.968  3955  4378 I AiAiEcho: Predicting[1]: { Feature:1, creation:2022-08-31T10:56:31.550Z, expiry:2022-08-31T16:56:31.550Z, isExpired: false}
08-31 12:23:04.969  3955  4378 I AiAiEcho: Ranked targets strategy: WEIGHTED, count: 1, ranking metadata: { cardId: WEATHER-569377243, card type: 1, update time: 2022-08-31T10:56:31.550Z, expiration time: 2022-08-31T16:56:31.550Z, ranking metadata: RankingMetaData(urgency=0.653, priority=0.3, recency=1.0, rankScore=0.19590001, importantTimePoints=# kor@7bca4) }
08-31 12:23:04.970  1793  4140 I ActivityManager: Process org.jak_linux.dns66 (pid 24804) has died: fg  TOP
08-31 12:23:04.971  1793  2091 I libprocessgroup: Successfully killed process cgroup uid 10266 pid 24804 in 0ms
08-31 12:23:04.971  1793  4140 W ActivityManager: Scheduling restart of crashed service org.jak_linux.dns66/.vpn.AdVpnService in 1000ms for start-requested

After that, it starts up again automatically, but it's irritating to have to provoke the restart by opening (and hence crashing) the app.