AV debugging a console app on OSX

[jeffschwMSFT]

Repo:
• Dotnet new (console app)
• Load in VS Code
• Set breakpoint on Console.WriteLine
• Start debugging
o Adjust launch.json

The crash is immediate before the break point is hit. I hit it 6 times in a row, and then it is hit and miss happening about 1 out of 4 times. I believe this is today’s dotnet-cli, so there is not a newer one.

Process: dotnet [1135]
Path: /usr/local/share/dotnet/dotnet
Identifier: dotnet
Version: 0
Code Type: X86-64 (Native)
Parent Process: clrdbg [1134]
Responsible: Electron [1058]
User ID: 501

Date/Time: 2016-03-24 08:40:51.490 -0700
OS Version: Mac OS X 10.11.3 (15D21)
Report Version: 11
Anonymous UUID: C338F9E8-014F-0911-4231-3B3EA16021B4

Sleep/Wake UUID: 5E4DE1D4-C3FC-4757-9165-216FE084E771

Time Awake Since Boot: 6600 seconds
Time Since Wake: 920 seconds

System Integrity Protection: enabled

Crashed Thread: 3

Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: EXC_I386_GPFLT

Thread 3 Crashed:
0 libsystem_platform.dylib 0x00007fff8f1fdfbd platform_memmove$VARIANT$Haswell + 157
1 libcoreclr.dylib 0x000000010159836e DbgTransportSession::SendMessage(DbgTransportSession::Message, bool) + 302
2 libcoreclr.dylib 0x000000010159a29f DbgTransportSession::TransportWorker() + 3967
3 libcoreclr.dylib 0x0000000101598109 DbgTransportSession::TransportWorkerStatic(void_) + 9
4 libcoreclr.dylib 0x000000010152f178 CorUnix::CPalThread::ThreadEntry(void*) + 328
5 libsystem_pthread.dylib 0x00007fff8a2e3c13 _pthread_body + 131
6 libsystem_pthread.dylib 0x00007fff8a2e3b90 _pthread_start + 168
7 libsystem_pthread.dylib 0x00007fff8a2e1375 thread_start + 13

[sergiy-k]

cc @tzwlai Should this be fixed in RC2?

[gregg-miskelly]

I am not sure if this will turn out to be useful or not, but I caught this race once with PAL process logging enabled for both debugger and target processes. This starts from the CreateProcess of the target.

{0xf1fdb-0x101950550} TRACE [PROCESS] at PROCAddThread.2988: Thread 0x00007FE80E001E00 (id 0) added to the process thread list
{0xf1fdb-0x101950550} TRACE [PROCESS] at getPath.4162: file /Users/greggm/clicon/run/clicon exists
{0xf1fdb-0x101950550} TRACE [PROCESS] at InternalCreateProcess.1016: New process created: id=0xabf1
{0xf1fdb-0x101e9c880} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80C005A00 (id 0xf1fdb) added to the process thread list
{0xf1fdb-0x101950550} TRACE [PROCESS] at PROCAddThread.2988: Thread 0x00007FE80B806000 (id 0) added to the process thread list
{0xf2032-0x101e9c880} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80B80E400 (id 0xf2032) added to the process thread list
=telemetry,event-name="VS/Diagnostics/Debugger/clrdbg/ProcessCreate",properties={VS.Diagnostics.Debugger.clrdbg.Version="14.0.25005.0 built by: LAUNCHCMDSUPPORT(GREGGM5-GREGGM)",VS.Diagnostics.Debugger.clrdbg.OSFamily="Darwin",VS.Diagnostics.Debugger.clrdbg.KernelRelease="14.5.0"}
{0xf1fdb-0x101e9c880} TRACE [PROCESS] at Register.1503: PAL_RuntimeStartupHelper.Register startup '/clrst0000abf10000000056f973d2' continue '/clrco0000abf10000000056f973d2'
{0xf1fdb-0x101e9c880} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80B80F000 (id 0) added to the process thread list
{0xf2033-0x101e9c880} TRACE [PROCESS] at StartupHelperThread.1675: PAL's StartupHelperThread starting
{0xf1fdb-0x101950550} TRACE [PROCESS] at PROCAddThread.2988: Thread 0x00007FE80D001A00 (id 0) added to the process thread list
{0xf2035-0x101e9c880} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80D002600 (id 0xf2035) added to the process thread list
^running
(gdb)
~"{0xf1ffd-0x10d622b40} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FC07900B400 (id 0xf1ffd) added to the process thread list\n"
~"{0xf1ffd-0x10d622b40} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FC07900C000 (id 0) added to the process thread list\n"
~"{0xf1ffd-0x10d622b40} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FC07904F400 (id 0) added to the process thread list\n"
~"{0xf1ffd-0x10d622b40} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FC079800000 (id 0) added to the process thread list\n"
~"{0xf1ffd-0x10d622b40} TRACE [PROCESS] at PAL_NotifyRuntimeStarted.1785: PAL_NotifyRuntimeStarted opening startup '/clrst0000abf10000000056f973d2' continue '/clrco0000abf10000000056f973d2'\n"
{0xf2033-0x101e9c880} TRACE [PROCESS] at InvokeStartupCallback.1602: InvokeStartupCallback executing callback /Users/greggm/clicon/run/libcoreclr.dylib
{0xf2033-0x102d3c360} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80E002A00 (id 0xf2033) added to the process thread list
{0xf2033-0x101950550} TRACE [PROCESS] at PROCAddThread.2988: Thread 0x00007FE80C004E00 (id 0xf2033) added to the process thread list
{0xf2033-0x102d3c360} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80E009000 (id 0) added to the process thread list
{0xf2033-0x102d3c360} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80D00C400 (id 0) added to the process thread list
{0xf2050-0x102d3c360} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80B80FC00 (id 0) added to the process thread list
{0xf2035-0x101950550} TRACE [PROCESS] at PROCRemoveThread.3046: Thread 00007FE80D001A00 removed from the process thread list
{0xf2033-0x101950550} TRACE [PROCESS] at PROCRemoveThread.3032: Thread 0x00007FE80C004E00 (id 0xf2033) removed from the process thread list
{0xf2035-0x102d3c360} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80B826000 (id 0xf2035) added to the process thread list
{0xf2035-0x101e9c880} TRACE [PROCESS] at PROCRemoveThread.3159: Thread 0x00007FE80D002600 (id 0xf2035) removed from the process thread list
{0xf2033-0x101e9c880} TRACE [PROCESS] at PROCRemoveThread.3159: Thread 0x00007FE80B80F000 (id 0xf2033) removed from the process thread list
{0xf2035-0x102d3c360} TRACE [PROCESS] at PROCRemoveThread.3159: Thread 0x00007FE80B826000 (id 0xf2035) removed from the process thread list
~"{0xf203f-0x10d622b40} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FC07C000000 (id 0) added to the process thread list\n"
{0xf2033-0x102d3c360} TRACE [PROCESS] at PROCRemoveThread.3173: Thread 00007FE80E002A00 removed from the process thread list
{0xf204f-0x101950550} TRACE [PROCESS] at PROCAddThread.2988: Thread 0x00007FE80C004E00 (id 0xf204f) added to the process thread list
=thread-created,id="991229"
~"{0xf1ffd-0x10d622b40} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FC07B021E00 (id 0) added to the process thread list\n"
=message,text="The target process is running .NET Core build dotnet/coreclr#1. In this build, launch may not be reliable. Please upgrade to targeting NETStandard 1.0.0-rc2-23901 or newer.",send-to="message-box",severity="warning"
=telemetry,event-name="VS/Diagnostics/Debugger/clrdbg/TargetRuntimeLoaded",properties={VS.Diagnostics.Debugger.clrdbg.TargetRuntimeVersion.MS="0x00040006",VS.Diagnostics.Debugger.clrdbg.TargetRuntimeVersion.LS="0x00010000",VS.Diagnostics.Debugger.clrdbg.Version="14.0.25005.0 built by: LAUNCHCMDSUPPORT(GREGGM5-GREGGM)",VS.Diagnostics.Debugger.clrdbg.OSFamily="Darwin",VS.Diagnostics.Debugger.clrdbg.KernelRelease="14.5.0"}
=library-loaded,id="{5d134f95-2970-4d83-8cec-e269b96e23ae}",target-name="/Users/greggm/clicon/run/mscorlib.dll",host-name="/Users/greggm/clicon/run/mscorlib.dll",symbols-loaded="0",base-address="0x10f55d000",size="2367488"
=library-loaded,id="{5d134f95-2970-4d83-8cec-e269b96e23b0}",target-name="/Users/greggm/clicon/run/clicon.dll",host-name="/Users/greggm/clicon/run/clicon.dll",symbols-loaded="1",base-address="0x10f54a000",size="32768"
=library-loaded,id="{5d134f95-2970-4d83-8cec-e269b96e23b4}",target-name="/Users/greggm/clicon/run/System.Runtime.dll",host-name="/Users/greggm/clicon/run/System.Runtime.dll",symbols-loaded="0",base-address="0x110eee000",size="49152"
=library-loaded,id="{5d134f95-2970-4d83-8cec-e269b96e23b6}",target-name="/Users/greggm/clicon/run/System.Console.dll",host-name="/Users/greggm/clicon/run/System.Console.dll",symbols-loaded="0",base-address="0x110f11000",size="106496"
~"{0xf203b-0x10d622b40} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FC07B02E400 (id 0xf203b) added to the process thread list\n"
{0xf2032-0x102d3c360} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80E002A00 (id 0xf2032) added to the process thread list
-ASSERT FAILED: "\"Failed to get active frame?\""
    Expression: 0
    Location:   line 240 in /Users/greggm/clrdbg/src/debugger/concord/impl/ManagedDM/V2/V2InstrBreakpoint.cpp
    Function:   Fire
{0xf204f-0x101950550} TRACE [PROCESS] at PROCGetProcessStatus.3295: Looking for status of process; trying wait(){0xf204f-0x101950550} TRACE [PROCESS] at PROCGetProcessStatus.3341: waitpid() failed with ECHILD; calling kill instead{0xf204f-0x101950550} TRACE [PROCESS] at PROCGetProcessStatus.3394: State of process 0x0000abf1 : 3 (exit code 0)
{0xf2050-0x102d3c360} TRACE [PROCESS] at PROCRemoveThread.3173: Thread 00007FE80D00C400 removed from the process thread list
ASSERT FAILED: "Failed to continue the process"
    Expression: hr == S_OK
    Location:   line 966 in /Users/greggm/clrdbg/src/debugger/concord/impl/ManagedDM/V2/V2DbiCallback.cpp
    Function:   ContinueExecution
{0xf1ffc-0x101950550} TRACE [PROCESS] at PROCRemoveThread.3046: Thread 00007FE80E001E00 removed from the process thread list
*stopped,reason="exited",exit-code="0"
(gdb)
{0xf204f-0x101950550} TRACE [PROCESS] at PROCRemoveThread.3032: Thread 0x00007FE80C004E00 (id 0xf204f) removed from the process thread list
{0xf2342-0x101950550} TRACE [PROCESS] at PROCAddThread.2988: Thread 0x00007FE80D001A00 (id 0xf2342) added to the process thread list
{0xf204f-0x102d3c360} TRACE [PROCESS] at PROCRemoveThread.3173: Thread 00007FE80E009000 removed from the process thread list
{0xf2342-0x101950550} TRACE [PROCESS] at PROCAddThread.2988: Thread 0x00007FE80C004E00 (id 0) added to the process thread list
{0xf2343-0x101e9c880} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80D002600 (id 0xf2343) added to the process thread list
{0xf2032-0x101950550} TRACE [PROCESS] at PROCRemoveThread.3046: Thread 00007FE80B806000 removed from the process thread list
{0xf2032-0x101e9c880} TRACE [PROCESS] at PROCRemoveThread.3173: Thread 00007FE80B80E400 removed from the process thread list
{0xf2032-0x102d3c360} TRACE [PROCESS] at PROCRemoveThread.3159: Thread 0x00007FE80E002A00 (id 0xf2032) removed from the process thread list
{0xf2343-0x102d3c360} TRACE [PROCESS] at PROCAddThread.3115: Thread 0x00007FE80E002A00 (id 0xf2343) added to the process thread list
^R
{0xf2342-0x101950550} TRACE [PROCESS] at PROCRemoveThread.3046: Thread 00007FE80D001A00 removed from the process thread list

[gregg-miskelly]

I have a core dump of the issue. The crash is while processing a MT_ReadMemory message. Issue appears to be that pMessage->m_pbDataBlock points to junk.

[mikem8361]

Fix with PR dotnet/coreclr#3976

[gregg-miskelly]

This is related to dotnet/coreclr#3987