Software Diagnostics Library

15th Anniversary

Dmitry Vostokov — Thu, 17 Jun 2021 19:55:23 +0000

To celebrate 15 (0xF) years of Software Diagnostics Library (former Crash Dump Analysis blog) this August, Software Diagnostics Services opens a Summer sale of Memory Dump Analysis Anthology Volume Set in PDF format with a 50% discount. It also includes Volume 14 once it is published on the anniversary date. The sale end date is undefined and equals to min(salesTarget.dateAchieved(), Date(“14-August-2021”)). https://www.patterndiagnostics.com/mdaa-volumes

Trace Analysis Patterns (Part 208)

Dmitry Vostokov — Sat, 29 May 2021 17:01:10 +0000

Most of the time tracing and logging is done sequentially, for example, when a service or application is restarted after the crash or bug fix, or the host is rebooted. Then we can glue all resulted traces together (similar to Glued Stack Trace) into one large Serial Trace. Here we assume the same Trace Schema for all individual traces and logs. It can also be considered as flattening a 2-dimensional Trace Tensor:

This allows us to apply various trace and log analysis patterns to the unified Serial Trace instead of doing Inter-Correlation (vs. Intra-Correlation).

Serial Trace is different from Meta Trace which is a trace about trace and Master Trace which is a trace we compare all other traces to. It is similar to Trace Mask when there is no overlap in time. Also, Serial Trace is not a reverse of Split Trace in a general case due to Visibility Limits between individual traces.

When gluing traces together, Ornament messages may be added to serve as a boundary between fragments.

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Trace Analysis Patterns (Part 207)

Dmitry Vostokov — Mon, 26 Apr 2021 21:41:27 +0000

Trace Schema can be represented as Schema Trace or, avoiding naming confusion, Definition Trace. The resulting trace looses ordering (similar to unordered Message Set) but allows application of trace and log analysis patterns, especially if some order is fixed, for example, alphabetical for names or original presentation column arrangement. Schema definition Trace Schema can be represented as another Definition Trace as illustrated in the following diagram:

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Trace Analysis Patterns (Part 206)

Dmitry Vostokov — Sun, 11 Apr 2021 22:21:39 +0000

Most of trace and log analysis pattern illustrations using Dia|gram language are of these two general forms:

Although the first form represents typical ETW trace attributes, the analysis pattern descriptions are usually independent of attribute name semantics. It, therefore, makes sense to generalize such forms into the following Trace Schema forms, with ATIDs for Adjoint Threads of Activity for the first form, and with FIDs for Features of Activity for the second form:

Such Trace Schemas are useful for various trace and log joins other than Trace Mask.

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Crash Dump Analysis Patterns (Part 213b)

Dmitry Vostokov — Fri, 09 Apr 2021 21:10:44 +0000

Previously we introduced Rough Stack Trace analysis pattern for unmanaged space. However, similar collection of symbolic references is possible for managed space (without included unmanaged references we see in Caller-n-Callee). Although the output is noisy, it can be filtered by external tools. The simple WinDbg script outputs managed method descriptors from a stack segment where boundaries were taken from the output of !teb command (this works even for complete memory dumps with .NET Core SOS extension after switching to the appropriate process context):

1: kd> .for (r $t0=000000a7d4d9c000; @$t0 < 000000a7d4db0000; r $t0=@$t0+@$ptrsize) {.if (poi(@$t0) > 7ff000000000) { .printf "---\n"; !IP2MD poi(@$t0) }} [...] Failed to request MethodData, not in JIT code range --- MethodDesc: 00007ff8f7da4fd8 Method Name: System.Windows.Forms.Application.Run(System.Windows.Forms.Form) Class: 00007ff8f7d9c1f0 MethodTable: 00007ff8f7da50b0 mdToken: 0000000006000AB8 Module: 00007ff8f7c599a0 IsJitted: yes Current CodeAddr: 00007ff953059310 Version History: ILCodeVersion: 0000000000000000 ReJIT ID: 0 IL Addr: 00007ff952a055d7 CodeAddr: 00007ff953059310 (ReadyToRun) NativeCodeVersion: 0000000000000000 — MethodDesc: 00007ff8f7c26d98 Method Name: LINQPad.UIProgram.Run() Class: 00007ff8f7c32d30 MethodTable: 00007ff8f7c28280 mdToken: 00000000060001AF Module: 00007ff8f7bc2780 IsJitted: yes Current CodeAddr: 00007ff8f8328c50 Version History: ILCodeVersion: 0000000000000000 ReJIT ID: 0 IL Addr: 000002316969a53c CodeAddr: 00007ff8f8328c50 (MinOptJitted) NativeCodeVersion: 0000000000000000 — MethodDesc: 00007ff8f7c26c60 Method Name: LINQPad.UIProgram.Go(System.String[]) Class: 00007ff8f7c32d30 MethodTable: 00007ff8f7c28280 mdToken: 00000000060001A4 Module: 00007ff8f7bc2780 IsJitted: yes Current CodeAddr: 00007ff8f7f23890 Version History: ILCodeVersion: 0000000000000000 ReJIT ID: IL Addr: 0000023169699840 CodeAddr: 00007ff8f7f23890 (MinOptJitted) NativeCodeVersion: 0000000000000000 — Failed to request MethodData, not in JIT code range — MethodDesc: 00007ff8f7c26c00 Method Name: LINQPad.UIProgram.Start(System.String[]) Class: 00007ff8f7c32d30 MethodTable: 00007ff8f7c28280 mdToken: 00000000060001A0 Module: 00007ff8f7bc2780 IsJitted: yes Current CodeAddr: 00007ff8f7b2fce0 Version History: ILCodeVersion: 0000000000000000 ReJIT ID: 0 IL Addr: 00000231696996fc CodeAddr: 00007ff8f7b2fce0 (MinOptJitted) NativeCodeVersion: 0000000000000000 — MethodDesc: 00007ff8f7bc64d8 Method Name: LINQPad.UI.Loader.Main(System.String[]) Class: 00007ff8f7c09508 MethodTable: 00007ff8f7bc64f0 mdToken: 0000000006000346 Module: 00007ff8f7bc2780 IsJitted: yes Current CodeAddr: 00007ff8f7b26400 Version History: ILCodeVersion: 0000000000000000 ReJIT ID: 0 IL Addr: 00000231696ab048 CodeAddr: 00007ff8f7b26400 (MinOptJitted) NativeCodeVersion: 0000000000000000 — Failed to request MethodData, not in JIT code range — Failed to request MethodData, not in JIT code range — Failed to request MethodData, not in JIT code range — Failed to request MethodData, not in JIT code range — […]

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Trace Analysis Patterns (Part 205)

Dmitry Vostokov — Sun, 04 Apr 2021 17:23:52 +0000

When looking at trace and log messages we are usually interested in some features (for example, when doing feature engineering, but not limited to) which can be labelled via Feature IDs (FID). Messages that have the same FID value constitute Feature of Activity, similar to Thread of Activity (or Adjoint Thread of Activity).

Such Features of Activity can span several (A)TIDs in contrast to Fibers of Activity which are confined to the same (A)TID and may have different FID values. Therefore, inside (A)TID there can be several Features of Activity having different FID values.

This analysis pattern serves as a base for other data science analysis patterns we add next.

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Crash Dump Analysis Patterns (Part 276)

Dmitry Vostokov — Sat, 03 Apr 2021 22:21:35 +0000

In simple exception cases, we have exception record, for example from Stored Exception corresponding to exception context, for example:

0:000> .exr -1 ExceptionAddress: 00000001400247ae (TestWER64!CTestDefaultDebuggerDlg::OnBnClickedButton1+0×000000000000007e) ExceptionCode: c0000005 (Access violation) ExceptionFlags: 00000000 NumberParameters: 2 Parameter[0]: 0000000000000001 Parameter[1]: 0000000000000000 Attempt to write to address 0000000000000000

0:000> .ecxr rax=0000000000000000 rbx=0000000000000001 rcx=000000000014fd20 rdx=00000000000003e8 rsi=000000000014fd20 rdi=000000014002daa0 rip=00000001400247ae rsp=000000000014efd0 rbp=0000000000000111 r8=0000000000000000 r9=0000000140024730 r10=0000000140024730 r11=000000000014f0d0 r12=0000000000000000 r13=00000000000003e8 r14=0000000000000110 r15=0000000000000001 iopl=0 nv up ei pl zr na po nc cs=0033 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010246 TestWER64!CTestDefaultDebuggerDlg::OnBnClickedButton1+0×7e: 00000001`400247ae c704250000000000000000 mov dword ptr [0],0 ds:00000000`00000000=????????

In other cases, we may have missing context:

0:000> .excr Minidump doesn't have an exception context Unable to get exception context, HRESULT 0x80004002

invalid context (see also Invalid Exception Information) in the output of !analyze -v command:

CONTEXT: 00007ffb54bd1e60 -- (.cxr 0x7ffb54bd1e60) rax=15ff480001191885 rbx=ff48c88b48000000 rcx=00441f0f00044c3c rdx=08ba3824448d4c00 rsi=4838244c8b480001 rdi=0058b9413024448d rip=00441f0f00044a04 rsp=441f0f00044bd315 rbp=18e4840fc0850000 r8=4c20244489480000 r9=244c89444024448d r10=15ff48a9518d4130 r11=00441f0f00044ebc r12=0118c1840fc08500 r13=8b4840244c8b4800 r14=d88b0000003ee8d7 r15=15ff4838244c8b48 iopl=0 vip vif ov dn ei pl nz na pe nc cs=2183 ss=044c ds=4800 es=f98b fs=ff48 gs=5315 efl=441f0f00 00441f0f`00044a04 ?? ??? Resetting default scope

and valid context but not corresponding to stored exception record:

0:000> .ecxr rax=00007ffe0a6a9618 rbx=0000024a3aa44020 rcx=0000000100000001 rdx=0000000000000001 rsi=0000024a3abff3e8 rdi=0000024a3abfb5c8 rip=00007ffe9768d759 rsp=000000dc0fd7caf0 rbp=000000dc0fd7d160 r8=0000024a00000007 r9=0000024a5ce8bc80 r10=0000000000000000 r11=0000000000000000 r12=0000024a3abfad90 r13=0000024a3aa44020 r14=0000000000000000 r15=0000024a3abfb5e0 iopl=0 nv up ei pl nz na pe nc cs=0033 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00000202 KERNELBASE!RaiseException+0x69: 00007ffe`9768d759 0f1f440000 nop dword ptr [rax+rax]

0:000> .exr -1 ExceptionAddress: 00007ffe0a6a9609 ExceptionCode: c0000005 (Access violation) ExceptionFlags: 00000000 NumberParameters: 2 Parameter[0]: 0000000000000001 Parameter[1]: 0000000000000000 Attempt to write to address 0000000000000000

However, Exception Stack Trace may be available with JIT Code address :

0:000> kL # Child-SP RetAddr Call Site 00 000000dc`0fd7b558 00007ffe`976b0d40 ntdll!NtWaitForMultipleObjects+0x14 01 000000dc`0fd7b560 00007ffe`976b0c3e KERNELBASE!WaitForMultipleObjectsEx+0xf0 02 000000dc`0fd7b850 00007ffe`994cf6aa KERNELBASE!WaitForMultipleObjects+0xe 03 000000dc`0fd7b890 00007ffe`994cf0e6 kernel32!WerpReportFaultInternal+0x58a 04 000000dc`0fd7b9b0 00007ffe`9776c439 kernel32!WerpReportFault+0xbe 05 000000dc`0fd7b9f0 00007ffe`99cd4b63 KERNELBASE!UnhandledExceptionFilter+0x3d9 06 000000dc`0fd7bb10 00007ffe`99cbbb16 ntdll!RtlUserThreadStart$filt$0+0xa2 07 000000dc`0fd7bb50 00007ffe`99cd130f ntdll!_C_specific_handler+0x96 08 000000dc`0fd7bbc0 00007ffe`99c7b5e4 ntdll!RtlpExecuteHandlerForException+0xf 09 000000dc`0fd7bbf0 00007ffe`99c7b335 ntdll!RtlDispatchException+0x244 0a 000000dc`0fd7c300 00007ffe`9768d759 ntdll!RtlRaiseException+0x185 0b 000000dc`0fd7caf0 00007ffe`6986b259 KERNELBASE!RaiseException+0x69 0c 000000dc`0fd7cbd0 00007ffe`6986b28b coreclr!NakedThrowHelper2+0x9 0d 000000dc`0fd7cc00 00007ffe`6986b295 coreclr!NakedThrowHelper_RspAligned+0x1e 0e 000000dc`0fd7d128 00007ffe`0a6a9609 coreclr!NakedThrowHelper_FixRsp+0×5 0f 000000dc`0fd7d130 00007ffe`0a548023 0×00007ffe`0a6a9609 10 000000dc`0fd7d170 00007ffe`0a547734 0×00007ffe`0a548023 11 000000dc`0fd7d230 00000000`627311e5 0×00007ffe`0a547734 12 000000dc`0fd7d290 00007ffe`62b50fe7 PresentationCore+0×4011e5 13 000000dc`0fd7d2d0 00007ffe`62a35840 PresentationFramework+0xbb0fe7 14 000000dc`0fd7d310 00007ffe`62b51a60 PresentationFramework+0xa95840 15 000000dc`0fd7d350 00000000`62732e22 PresentationFramework+0xbb1a60 16 000000dc`0fd7d390 00000000`62757c42 PresentationCore+0×402e22 17 000000dc`0fd7d3d0 00007ffe`0a5448f3 PresentationCore+0×427c42 18 000000dc`0fd7d410 00007ffe`0a548023 0×00007ffe`0a5448f3 19 000000dc`0fd7d450 00000000`62740e19 0×00007ffe`0a548023 1a 000000dc`0fd7d510 00000000`62732b6a PresentationCore+0×410e19 1b 000000dc`0fd7d580 00000000`62757c42 PresentationCore+0×402b6a 1c 000000dc`0fd7d5c0 00007ffe`0a5448f3 PresentationCore+0×427c42 1d 000000dc`0fd7d600 00007ffe`0a548023 0×00007ffe`0a5448f3 1e 000000dc`0fd7d640 00007ffe`0a547734 0×00007ffe`0a548023 1f 000000dc`0fd7d700 00007ffe`0a550211 0×00007ffe`0a547734 20 000000dc`0fd7d760 00007ffe`0a558efd 0×00007ffe`0a550211 21 000000dc`0fd7d7a0 00007ffe`0a55ebb1 0×00007ffe`0a558efd 22 000000dc`0fd7d860 00007ffe`0a564474 0×00007ffe`0a55ebb1 23 000000dc`0fd7d8b0 00007ffe`0a550eff 0×00007ffe`0a564474 24 000000dc`0fd7d9e0 00007ffe`0a550692 0×00007ffe`0a550eff 25 000000dc`0fd7da70 00007ffe`0a54967d 0×00007ffe`0a550692 26 000000dc`0fd7dae0 00007ffe`0a549596 0×00007ffe`0a54967d 27 000000dc`0fd7db70 00007ffe`0a548ac7 0×00007ffe`0a549596 28 000000dc`0fd7dbc0 00007ffe`0a5488f5 0×00007ffe`0a548ac7 29 000000dc`0fd7dc20 00007ffe`0a54920c 0×00007ffe`0a5488f5 2a 000000dc`0fd7dc70 00007ffe`0a548f07 0×00007ffe`0a54920c 2b 000000dc`0fd7dd00 00007ffe`09d2d772 0×00007ffe`0a548f07 2c 000000dc`0fd7de00 00007ffe`995ae858 0×00007ffe`09d2d772 2d 000000dc`0fd7de80 00007ffe`995ae299 user32!UserCallWinProcCheckWow+0×2f8 2e 000000dc`0fd7e010 00007ffe`0a18011b user32!DispatchMessageWorker+0×249 2f 000000dc`0fd7e090 00007ffe`69557ec3 0×00007ffe`0a18011b 30 000000dc`0fd7e150 00007ffe`695553a1 WindowsBase+0×197ec3 31 000000dc`0fd7e1e0 00007ffe`6955534e WindowsBase+0×1953a1 32 000000dc`0fd7e210 00007ffe`6276966c WindowsBase+0×19534e 33 000000dc`0fd7e240 00007ffe`62767ccd PresentationFramework+0×7c966c 34 000000dc`0fd7e270 00007ffe`62764c5c PresentationFramework+0×7c7ccd 35 000000dc`0fd7e2c0 00007ffe`09d1618e PresentationFramework+0×7c4c5c 36 000000dc`0fd7e2f0 00007ffe`6986a2f3 0×00007ffe`09d1618e 37 000000dc`0fd7e340 00007ffe`697a2fcc coreclr!CallDescrWorkerInternal+0×83 38 000000dc`0fd7e380 00007ffe`697c22b3 coreclr!MethodDescCallSite::CallTargetWorker+0×268 39 (Inline Function) ——–`——– coreclr!MethodDescCallSite::Call+0xb 3a 000000dc`0fd7e4c0 00007ffe`697c207e coreclr!RunMainInternal+0×11f 3b 000000dc`0fd7e5f0 00007ffe`697c1be1 coreclr!RunMain+0xd2 3c 000000dc`0fd7e6a0 00007ffe`697c1908 coreclr!Assembly::ExecuteMainMethod+0×1cd 3d 000000dc`0fd7ea30 00007ffe`69789ad2 coreclr!CorHost2::ExecuteAssembly+0×1c8 3e 000000dc`0fd7eba0 00007ffe`7d502c72 coreclr!coreclr_execute_assembly+0xe2 3f (Inline Function) ——–`——– hostpolicy!coreclr_t::execute_assembly+0×2b 40 000000dc`0fd7ec40 00007ffe`7d502ed7 hostpolicy!run_app_for_context+0×3be 41 000000dc`0fd7edd0 00007ffe`7d503b6b hostpolicy!run_app+0×37 42 000000dc`0fd7ee10 00007ffe`7d5839ea hostpolicy!corehost_main+0xfb 43 000000dc`0fd7efd0 00007ffe`7d587358 hostfxr!execute_app+0×206 44 (Inline Function) ——–`——– hostfxr!?A0×83a23e19::read_config_and_execute+0×10a 45 000000dc`0fd7f0c0 00007ffe`7d585b5f hostfxr!fx_muxer_t::handle_exec_host_command+0×214 46 000000dc`0fd7f1b0 00007ffe`7d582029 hostfxr!fx_muxer_t::execute+0×39b 47 000000dc`0fd7f2f0 00007ff6`3aede0b0 hostfxr!hostfxr_main_startupinfo+0×89 48 000000dc`0fd7f3f0 00007ff6`3aede418 ApplicationA_exe!exe_start+0×620 49 000000dc`0fd7f5d0 00007ff6`3aedfef8 ApplicationA_exe!wmain+0×124 4a (Inline Function) ——–`——– ApplicationA_exe!invoke_main+0×22 4b 000000dc`0fd7f740 00007ffe`99477034 ApplicationA_exe!__scrt_common_main_seh+0×10c 4c 000000dc`0fd7f780 00007ffe`99c7d0d1 kernel32!BaseThreadInitThunk+0×14 4d 000000dc`0fd7f7b0 00000000`00000000 ntdll!RtlUserThreadStart+0×21

0:000> u 00007ffe`0a6a9609 00007ffe`0a6a9609 c70001000000 mov dword ptr [rax],1 00007ffe`0a6a960f 90 nop 00007ffe`0a6a9610 90 nop 00007ffe`0a6a9611 488d6500 lea rsp,[rbp] 00007ffe`0a6a9615 5d pop rbp 00007ffe`0a6a9616 c3 ret 00007ffe`0a6a9617 0019 add byte ptr [rcx],bl 00007ffe`0a6a9619 0502000552 add eax,52050002h

In the case of .NET Core dump, we can use Saved Exception Context to get the original exception:

0:000> dp coreclr!g_SavedExceptionInfo 00007ffe`69bd57f0 00000000`c0000005 00000000`00000000 00007ffe`69bd5800 00007ffe`0a6a9609 00000000`00000002 00007ffe`69bd5810 00000000`00000001 00000000`00000000 00007ffe`69bd5820 00000000`00000000 00000000`00000000 00007ffe`69bd5830 00000000`00000000 00000000`00000000 00007ffe`69bd5840 00000000`00000000 00000000`00000000 00007ffe`69bd5850 00000000`00000000 00000000`00000000 00007ffe`69bd5860 00000000`00000000 00000000`00000000

0:000> dt coreclr!g_SavedExceptionInfo +0x000 m_ExceptionRecord : _EXCEPTION_RECORD +0x0a0 m_ExceptionContext : _CONTEXT +0x570 m_Crst : CrstStatic

0:000> .cxr coreclr!g_SavedExceptionInfo+a0 rax=0000000000000000 rbx=0000024a3aa44020 rcx=0000024a3aa1d210 rdx=0000024a3aa44020 rsi=0000024a3abff3e8 rdi=0000024a3abfb5c8 rip=00007ffe0a6a9609 rsp=000000dc0fd7d130 rbp=000000dc0fd7d160 r8=0000024a3abff3e8 r9=0000000000000000 r10=0000000000000000 r11=000000dc0fd7d090 r12=0000024a3abfad90 r13=0000024a3aa44020 r14=0000000000000000 r15=0000024a3abfb5e0 iopl=0 nv up ei pl zr na po nc cs=0033 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010246 00007ffe`0a6a9609 c70001000000 mov dword ptr [rax],1 ds:00000000`00000000=????????

This may also work in the case of invalid or missing exception information in .NET Core dumps:

0:000> .exr -1 ExceptionAddress: 0000000000000000 ExceptionCode: 80000003 (Break instruction exception) ExceptionFlags: 00000000 NumberParameters: 0

0:000> .excr Minidump doesn't have an exception context Unable to get exception context, HRESULT 0x80004002

In some other unmanaged cases, we can use probe Execution Residue values around some exception processing symbols as in the case of Hidden Exceptions, but this may not work if such values are overwritten or no longer available.

A similar approach is available for .NET Framework despite the type not available:

0:000> x clr!g_SavedExceptionInfo 00007ffc`efc01f40 clr!g_SavedExceptionInfo =

0:000> dt clr!g_SavedExceptionInfo Symbol clr!g_SavedExceptionInfo not found.

0:000> .cxr clr!g_SavedExceptionInfo+a0 rax=0000000000000000 rbx=0000000002f8b8a0 rcx=0000000002f27ee8 rdx=0000000002f8a598 rsi=0000000002f8a598 rdi=0000000002fa1028 rip=00007ffc8fcb0829 rsp=000000000113e5b0 rbp=000000000113e5e0 r8=0000000002fa1028 r9=0000000000000000 r10=00007ff480140018 r11=00007ffc8fba8ae8 r12=0000000000000002 r13=0000000000000202 r14=0000000000000001 r15=0000000000000000 iopl=0 nv up ei pl zr na po nc cs=0033 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010246 00007ffc`8fcb0829 c70001000000 mov dword ptr [rax],1 ds:00000000`00000000=????????

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Trace Analysis Patterns (Part 204)

Dmitry Vostokov — Sun, 07 Mar 2021 11:34:38 +0000

Trace Intra-Correlation may be quite elaborate and include analysis of 2-dimensional Weaves of Activity. A similar 2-dimensional metaphor can be applied to Inter-Correlation between several artefacts such as traces and logs, configuration information including infrastructure as code (Small DA+TA), telemetry and event streams, memory dumps (Adjoint Spaces, Trace Presheaf, Memory Fibration, State Dump). All these memory patches, layers, and Trace Fabrics are “sewn” together by Braids, Threads, Adjoint Threads, Strands, Cords, and Weaves of Activities. We call this pattern Trace Quilt but analogy with quilting and quilts.

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Crash Dump Analysis Patterns (Part 275)

Dmitry Vostokov — Wed, 03 Mar 2021 20:55:39 +0000

If we have Step Dumps or Evental Dumps or simply some different memory dumps, for example, from Fiber Bundle and Orbifold memory spaces, we may run debugger commands across them. Then we can track changes in their output like we did in Stack Trace Change analysis pattern. We call the generalization of the latter pattern Structure Sheaf by analogy with structure sheaves of ringed spaces in mathematics. Here we metaphorically treat sequences of debugger commands applied to memory areas (memory structures) as rings of functions on open subsets. We originally wanted to call this analysis pattern Stack Trace (command) for one command and Stack Trace Collection (commands) for a set of commands but realized that the stack trace analogy here makes sense only for sequential memory dumps ordered in time and not for memory dumps taken from different sources.

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Crash Dump Analysis Patterns (Part 274)

Dmitry Vostokov — Sun, 31 Jan 2021 23:55:28 +0000

COM Exceptions are Software Exceptions and their information can be extracted from C++ Exception record as shown in this post. Here we show the case of Nested and Hidden Exceptions.

We see a COM exception raising function on Exception Stack Trace:

0:008> .exr -1 ExceptionAddress: 00007ff97800cadf (ntdll!LdrpICallHandler+0x000000000000000f) ExceptionCode: c0000409 (Security check failure or stack buffer overrun) ExceptionFlags: 00000001 NumberParameters: 1 Parameter[0]: 000000000000000a Subcode: 0xa FAST_FAIL_GUARD_ICALL_CHECK_FAILURE

0:008> kL *** Stack trace for last set context - .thread/.cxr resets it # Child-SP RetAddr Call Site 00 0000009e`393f9e78 00007ff9`7802184f ntdll!LdrpICallHandler+0xf 01 0000009e`393f9e80 00007ff9`77fea889 ntdll!RtlpExecuteHandlerForException+0xf 02 0000009e`393f9eb0 00007ff9`780204be ntdll!RtlDispatchException+0x219 03 0000009e`393fa5c0 00007ff9`7800cb9e ntdll!KiUserExceptionDispatch+0x2e 04 0000009e`393fad78 00007ff9`72591030 ntdll!LdrpDispatchUserCallTarget+0xe 05 0000009e`393fad80 00007ff9`72594a52 VCRUNTIME140_APP!_CallSettingFrame+0x20 06 0000009e`393fadb0 00007ff9`7259e514 VCRUNTIME140_APP!__FrameHandler3::FrameUnwindToState+0x112 07 0000009e`393fae20 00007ff9`72593cc8 VCRUNTIME140_APP!__FrameHandler3::FrameUnwindToEmptyState+0x54 08 0000009e`393fae50 00007ff9`7259ee51 VCRUNTIME140_APP!__InternalCxxFrameHandler<__FrameHandler3>+0x10c 09 0000009e`393faeb0 00007ff8`f83ea850 VCRUNTIME140_APP!__CxxFrameHandler3+0x71 0a 0000009e`393faf00 00007ff9`780218cf PaintStudio_ViewModel!DllGetActivationFactory+0x100 0b 0000009e`393faf30 00007ff9`77f9d9b2 ntdll!RtlpExecuteHandlerForUnwind+0xf 0c 0000009e`393faf60 00007ff9`7259e9de ntdll!RtlUnwindEx+0x522 0d 0000009e`393fb670 00007ff9`72592955 VCRUNTIME140_APP!__FrameHandler3::UnwindNestedFrames+0xee 0e 0000009e`393fb760 00007ff9`72592d81 VCRUNTIME140_APP!CatchIt<__FrameHandler3>+0xb9 0f 0000009e`393fb800 00007ff9`72593dc4 VCRUNTIME140_APP!FindHandler<__FrameHandler3>+0x33d 10 0000009e`393fb970 00007ff9`7259ee51 VCRUNTIME140_APP!__InternalCxxFrameHandler<__FrameHandler3>+0x208 11 0000009e`393fb9d0 00007ff9`7802184f VCRUNTIME140_APP!__CxxFrameHandler3+0x71 12 0000009e`393fba20 00007ff9`77fea889 ntdll!RtlpExecuteHandlerForException+0xf 13 0000009e`393fba50 00007ff9`77fea643 ntdll!RtlDispatchException+0x219 14 0000009e`393fc160 00007ff9`759d3b29 ntdll!RtlRaiseException+0×153 15 0000009e`393fc9d0 00007ff9`72596220 KERNELBASE!RaiseException+0×69 16 0000009e`393fcab0 00007ff9`4919a58c VCRUNTIME140_APP!_CxxThrowException+0×90 17 0000009e`393fcb10 00007ff8`f8057628 vccorlib140_app!__abi_WinRTraiseCOMException+0×2c 18 0000009e`393fcb40 00007ff8`f8093e81 PaintStudio_ViewModel+0×7628 19 0000009e`393fcb70 00007ff8`f818f27f PaintStudio_ViewModel+0×43e81 1a 0000009e`393fcbc0 00007ff8`f818c26f PaintStudio_ViewModel+0×13f27f 1b 0000009e`393fcc90 00007ff8`f811935a PaintStudio_ViewModel+0×13c26f 1c 0000009e`393fcd40 00007ff8`f827ce8e PaintStudio_ViewModel+0xc935a 1d 0000009e`393fd110 00007ff8`f82723ab PaintStudio_ViewModel+0×22ce8e 1e 0000009e`393fd5c0 00007ff8`f83bf09d PaintStudio_ViewModel+0×2223ab 1f 0000009e`393fd7b0 00007ff8`f83c16bd PaintStudio_ViewModel+0×36f09d 20 0000009e`393fdc60 00007ff8`f80e1331 PaintStudio_ViewModel+0×3716bd 21 0000009e`393fdd10 00007ff7`2030d3b9 PaintStudio_ViewModel+0×91331 22 0000009e`393fdd50 00007ff7`202f772f PaintStudio_View+0×2d3b9 23 0000009e`393fddb0 00007ff7`202f702b PaintStudio_View+0×1772f 24 0000009e`393fdee0 00007ff7`202f520e PaintStudio_View+0×1702b 25 0000009e`393fe010 00007ff7`203266d6 PaintStudio_View+0×1520e 26 0000009e`393fe100 00007ff9`4af9d25b PaintStudio_View+0×466d6 27 0000009e`393fe140 00007ff9`4af9d1ce Windows_UI_Xaml!DirectUI::FrameworkApplicationGenerated:: OnActivatedProtected+0×4b 28 0000009e`393fe170 00007ff9`4af9ebe6 Windows_UI_Xaml!DirectUI::FrameworkApplication::DispatchGenericActivation+0×4a 29 0000009e`393fe1a0 00007ff9`4aeb39eb Windows_UI_Xaml!DirectUI::FrameworkView::OnActivated+0×186 2a (Inline Function) ——–`——– Windows_UI_Xaml!Microsoft::WRL::Callback::__l2::::operator()+0×15 2b 0000009e`393fe220 00007ff9`72cd55cf Windows_UI_Xaml!Microsoft::WRL::Details::DelegateArgTraits,IInspectable *>::*)(Windows::UI::Core::ICoreWindow *,IInspectable *)>::DelegateInvokeHelper,,-1,Windows::UI::Core::ICoreWindow *,IInspectable *>::Invoke+0×1b 2c 0000009e`393fe250 00007ff9`72cd8a22 twinapi_appcore!Microsoft::WRL::InvokeTraits<-2>:: InvokeDelegates<,Windows::Foundation:: ITypedEventHandler >+0×67 2d 0000009e`393fe2c0 00007ff9`76cb6a63 twinapi_appcore!Windows::ApplicationModel::Core:: CoreApplicationView::Activate+0×3d2 2e 0000009e`393fe430 00007ff9`76d1a036 rpcrt4!Invoke+0×73 2f 0000009e`393fe490 00007ff9`76c783b9 rpcrt4!Ndr64StubWorker+0xb56 30 0000009e`393feb30 00007ff9`76fd5d13 rpcrt4!NdrStubCall3+0xc9 31 0000009e`393feb90 00007ff9`76c99bab combase!CStdStubBuffer_Invoke+0×73 32 0000009e`393febd0 00007ff9`76fbd0e3 rpcrt4!CStdStubBuffer_Invoke+0×3b 33 (Inline Function) ——–`——– combase!InvokeStubWithExceptionPolicyAndTracing::__l6:: ::operator()+0×18 34 0000009e`393fec00 00007ff9`76fbced3 combase!ObjectMethodExceptionHandlingAction< >+0×43 35 (Inline Function) ——–`——– combase!InvokeStubWithExceptionPolicyAndTracing+0xa8 36 0000009e`393fec60 00007ff9`76fd9556 combase!DefaultStubInvoke+0×1c3 37 (Inline Function) ——–`——– combase!SyncStubCall::Invoke+0×22 38 0000009e`393fedb0 00007ff9`76fba4fa combase!SyncServerCall::StubInvoke+0×26 39 (Inline Function) ——–`——– combase!StubInvoke+0×259 3a 0000009e`393fedf0 00007ff9`76fda81b combase!ServerCall::ContextInvoke+0×42a 3b (Inline Function) ——–`——– combase!CServerChannel::ContextInvoke+0xc0 3c (Inline Function) ——–`——– combase!DefaultInvokeInApartment+0xc0 3d 0000009e`393ff1f0 00007ff9`76f701ac combase!ASTAInvokeInApartment+0×15b 3e 0000009e`393ff400 00007ff9`76f70a11 combase!AppInvoke+0×1ec 3f 0000009e`393ff490 00007ff9`76f918c2 combase!ComInvokeWithLockAndIPID+0×681 40 (Inline Function) ——–`——– combase!ComInvoke+0×1c1 41 0000009e`393ff7c0 00007ff9`76f90a99 combase!ThreadDispatch+0×272 42 0000009e`393ff890 00007ff9`76f947ba combase!ModernSTAState::HandleMessage+0×51 43 0000009e`393ff8e0 00007ff9`4eac92f5 combase!ModernSTAWaitContext::HandlePriorityEventsFromMessagePump+0×66 44 0000009e`393ff910 00007ff9`4eac8fee Windows_UI!Windows::UI::Core::CDispatcher::ProcessMessage+0×1b5 45 0000009e`393ff9c0 00007ff9`4eac8f21 Windows_UI!Windows::UI::Core::CDispatcher::WaitAndProcessMessagesInternal+0xae 46 0000009e`393ffad0 00007ff9`72cea89f Windows_UI!Windows::UI::Core::CDispatcher::WaitAndProcessMessages+0×31 47 0000009e`393ffb00 00007ff9`76eac235 twinapi_appcore!::operator()+0xff 48 0000009e`393ffbf0 00007ff9`77aa7c24 SHCore!_WrapperThreadProc+0xf5 49 0000009e`393ffcd0 00007ff9`77fed4d1 kernel32!BaseThreadInitThunk+0×14 4a 0000009e`393ffd00 00000000`00000000 ntdll!RtlUserThreadStart+0×21

We dump doubly dereferenced raw stack region around such exception processing calls:

0:008> dpp 0000009e`393fc160 0000009e`393fcb70 […] 0000009e`393fcb38 00007ff8`f8057628 cc003f4c`6115ffcc 0000009e`393fcb40 0000009e`393fcb88 0000009e`393fcb98 0000009e`393fcb48 000001e8`69af9450 00007ff9`491c6170 vccorlib140_app!Platform::COMException::`vftable’ 0000009e`393fcb50 000001e8`69af9450 00007ff9`491c6170 vccorlib140_app!Platform::COMException::`vftable’ […]

We see C++ Object references and apply object structure to them:

0:008> dt vccorlib140_app!Platform::COMException 000001e8`69af9450 +0×000 __VFN_table : 0×00007ff9`491c6170 +0×008 __VFN_table : 0×00007ff9`491c5bf8 +0×010 __VFN_table : 0×00007ff9`491c5e20 +0×018 __VFN_table : 0×00007ff9`491c5ec0 +0×020 __description : 0×000001e8`5e1e30a8 Void +0×028 __restrictedErrorString : 0×000001e8`5ba83728 Void +0×030 __restrictedErrorReference : (null) +0×038 __capabilitySid : (null) +0×040 __hresult : 0n-2147024894 +0×048 __restrictedInfo : 0×000001e8`699f4308 Void +0×050 __throwInfo : 0×00007ff9`491baf60 Void +0×058 __size : 0×40 +0×060 __prepare : Platform::IntPtr +0×068 __abi_reference_count : __abi_FTMWeakRefData +0×078 __abi_disposed : 0 +0×080 __abi_disposed : 0

0:008> du 0x000001e8`5e1e30a8 000001e8`5e1e30a8 "The system cannot find the file " 000001e8`5e1e30e8 "specified..."

0:008> du 0x000001e8`5ba83728 000001e8`5ba83728 "Error trying to initialize appli" 000001e8`5ba83768 "cation data storage folder"

0:008> !error 0n-2147024894 Error code: (HRESULT) 0x80070002 (2147942402) - The system cannot find the file specified.

- Dmitry Vostokov @ DumpAnalysis.org + TraceAnalysis.org -