Port ComWrappers 5.0 diagnostic changes back to master and add stowed exception array to minidumps (#43164)

Author: davmason

src/coreclr/src/debug/daccess/dacimpl.h

@@ -1482,6 +1482,7 @@ class ClrDataAccess
 #endif
 
 #ifdef FEATURE_COMWRAPPERS
+    BOOL DACGetComWrappersCCWVTableQIAddress(CLRDATA_ADDRESS ccwPtr, TADDR *vTableAddress, TADDR *qiAddress);
     BOOL DACIsComWrappersCCW(CLRDATA_ADDRESS ccwPtr);
     TADDR DACGetManagedObjectWrapperFromCCW(CLRDATA_ADDRESS ccwPtr);
     HRESULT DACTryGetComWrappersObjectFromCCW(CLRDATA_ADDRESS ccwPtr, OBJECTREF* objRef);
@@ -4036,4 +4037,36 @@ extern unsigned __int64 g_nFindStackTotalTime;
 
 #endif // #if defined(DAC_MEASURE_PERF)
 
+#ifdef FEATURE_COMWRAPPERS
+
+// Public contract for ExternalObjectContext, keep in sync with definition in
+// interoplibinterface.cpp
+struct ExternalObjectContextDACnterface
+{
+    PTR_VOID identity;
+    INT_PTR _padding1;
+    DWORD SyncBlockIndex;
+    INT64 _padding3;
+};
+
+typedef DPTR(ExternalObjectContextDACnterface) PTR_ExternalObjectContext;
+
+// Public contract for ManagedObjectWrapper, keep in sync with definition in
+// comwrappers.hpp
+struct ManagedObjectWrapperDACInterface
+{
+    PTR_VOID managedObject;
+    INT32 _padding1;
+    INT32 _padding2;
+    INT_PTR _padding3;
+    INT_PTR _padding4;
+    INT_PTR _padding6;
+    LONGLONG _refCount;
+    INT32 _padding7;
+};
+
+typedef DPTR(ManagedObjectWrapperDACInterface) PTR_ManagedObjectWrapper;
+
+#endif // FEATURE_COMWRAPPERS
+
 #endif // #ifndef __DACIMPL_H__

src/coreclr/src/debug/daccess/enummem.cpp

@@ -20,6 +20,11 @@
 #include "binder.h"
 #include "win32threadpool.h"
 
+#ifdef FEATURE_COMWRAPPERS
+#include <interoplibinterface.h>
+#include <interoplibabi.h>
+#endif // FEATURE_COMWRAPPERS
+
 extern HRESULT GetDacTableAddress(ICorDebugDataTarget* dataTarget, ULONG64 baseAddress, PULONG64 dacTableAddress);
 
 #if defined(DAC_MEASURE_PERF)
@@ -1056,10 +1061,10 @@ HRESULT ClrDataAccess::EnumMemDumpAllThreadsStack(CLRDataEnumMemoryFlags flags)
 {
     SUPPORTS_DAC;
 
-#ifdef FEATURE_COMINTEROP
+#if defined(FEATURE_COMINTEROP) || defined(FEATURE_COMWRAPPERS)
     // Dump the exception object stored in the WinRT stowed exception
     EnumMemStowedException(flags);
-#endif
+#endif // defined(FEATURE_COMINTEROP) || defined(FEATURE_COMWRAPPERS)
 
     HRESULT     status = S_OK;
     TSIZE_T     cbMemoryReported = m_cbMemoryReported;
@@ -1377,6 +1382,10 @@ HRESULT ClrDataAccess::EnumMemStowedException(CLRDataEnumMemoryFlags flags)
         return S_OK;
     }
 
+    // Make sure we include the whole stowed exception array so we can debug a stowed exception
+    // in a minidump
+    ReportMem(remoteStowedExceptionArray, stowedExceptionCount * sizeof(TADDR));
+
     for (ULONG i = 0; i < stowedExceptionCount; ++i)
     {
         // Read the i-th stowed exception
@@ -1389,6 +1398,8 @@ HRESULT ClrDataAccess::EnumMemStowedException(CLRDataEnumMemoryFlags flags)
             continue;
         }
 
+        ReportMem(remoteStowedException, sizeof(STOWED_EXCEPTION_INFORMATION_HEADER));
+
         // check if this is a v2 stowed exception
         STOWED_EXCEPTION_INFORMATION_V2 stowedException = { 0 };
         if (FAILED(m_pTarget->ReadVirtual(TO_CDADDR(remoteStowedException),
@@ -1399,6 +1410,8 @@ HRESULT ClrDataAccess::EnumMemStowedException(CLRDataEnumMemoryFlags flags)
             continue;
         }
 
+        ReportMem(remoteStowedException, sizeof(STOWED_EXCEPTION_INFORMATION_V2));
+
         // Read the full v2 stowed exception and get the CCW pointer out of it
         if (FAILED(m_pTarget->ReadVirtual(TO_CDADDR(remoteStowedException),
             (PBYTE)&stowedException, sizeof(STOWED_EXCEPTION_INFORMATION_V2), &bytesRead))
@@ -1429,6 +1442,21 @@ HRESULT ClrDataAccess::DumpStowedExceptionObject(CLRDataEnumMemoryFlags flags, C
     if (DACTryGetComWrappersObjectFromCCW(ccwPtr, &wrappedObjAddress) == S_OK)
     {
         managedExceptionObject = wrappedObjAddress;
+        // Now report the CCW itself
+        ReportMem(TO_TADDR(ccwPtr), sizeof(TADDR));
+        TADDR managedObjectWrapperPtrPtr = ccwPtr & InteropLib::ABI::DispatchThisPtrMask;
+        ReportMem(managedObjectWrapperPtrPtr, sizeof(TADDR));
+
+        // Plus its QI and VTable that we query to determine if it is a ComWrappers CCW
+        TADDR vTableAddress = NULL;
+        TADDR qiAddress = NULL;
+        DACGetComWrappersCCWVTableQIAddress(ccwPtr, &vTableAddress, &qiAddress);
+        ReportMem(vTableAddress, sizeof(TADDR));
+        ReportMem(qiAddress, sizeof(TADDR));
+
+        // And the MOW it points to
+        TADDR mow = DACGetManagedObjectWrapperFromCCW(ccwPtr);
+        ReportMem(mow, sizeof(ManagedObjectWrapperDACInterface));
     }
 #endif
 #ifdef FEATURE_COMINTEROP

src/coreclr/src/debug/daccess/request.cpp

@@ -23,36 +23,6 @@
 #ifdef FEATURE_COMWRAPPERS
 #include <interoplibinterface.h>
 #include <interoplibabi.h>
-
-// Public contract for ExternalObjectContext, keep in sync with definition in
-// interoplibinterface.cpp
-struct ExternalObjectContextDACnterface
-{
-    INT_PTR sentinel;
-    PTR_VOID identity;
-    INT_PTR _padding1;
-    DWORD _padding2;
-    INT64 _padding3;
-};
-
-typedef DPTR(ExternalObjectContextDACnterface) PTR_ExternalObjectContext;
-
-// Public contract for ManagedObjectWrapper, keep in sync with definition in
-// comwrappers.hpp
-struct ManagedObjectWrapperDACInterface
-{
-    PTR_VOID managedObject;
-    INT32 _padding1;
-    INT32 _padding2;
-    INT_PTR _padding3;
-    INT_PTR _padding4;
-    INT_PTR _padding6;
-    LONGLONG _refCount;
-    INT32 _padding7;
-};
-
-typedef DPTR(ManagedObjectWrapperDACInterface) PTR_ManagedObjectWrapper;
-
 #endif // FEATURE_COMWRAPPERS
 
 #ifndef TARGET_UNIX
@@ -4105,22 +4075,23 @@ PTR_IUnknown ClrDataAccess::DACGetCOMIPFromCCW(PTR_ComCallWrapper pCCW, int vtab
 #endif
 
 #ifdef FEATURE_COMWRAPPERS
-BOOL ClrDataAccess::DACIsComWrappersCCW(CLRDATA_ADDRESS ccwPtr)
+BOOL ClrDataAccess::DACGetComWrappersCCWVTableQIAddress(CLRDATA_ADDRESS ccwPtr, TADDR *vTableAddress, TADDR *qiAddress)
 {
-    // Read CCWs QI address and compare it to the managed object wrapper's implementation.
+    _ASSERTE(vTableAddress != NULL && qiAddress != NULL);
+
     HRESULT hr = S_OK;
     ULONG32 bytesRead = 0;
     TADDR ccw = CLRDATA_ADDRESS_TO_TADDR(ccwPtr);
-    TADDR vTableAddress = NULL;
-    if (FAILED(m_pTarget->ReadVirtual(ccw, (PBYTE)&vTableAddress, sizeof(TADDR), &bytesRead))
+    *vTableAddress = NULL;
+    if (FAILED(m_pTarget->ReadVirtual(ccw, (PBYTE)vTableAddress, sizeof(TADDR), &bytesRead))
         || bytesRead != sizeof(TADDR)
         || vTableAddress == NULL)
     {
         return FALSE;
     }
 
-    TADDR qiAddress = NULL;
-    if (FAILED(m_pTarget->ReadVirtual(vTableAddress, (PBYTE)&qiAddress, sizeof(TADDR), &bytesRead))
+    *qiAddress = NULL;
+    if (FAILED(m_pTarget->ReadVirtual(*vTableAddress, (PBYTE)qiAddress, sizeof(TADDR), &bytesRead))
         || bytesRead != sizeof(TADDR)
         || qiAddress == NULL)
     {
@@ -4130,15 +4101,22 @@ BOOL ClrDataAccess::DACIsComWrappersCCW(CLRDATA_ADDRESS ccwPtr)
 
 #ifdef TARGET_ARM
     // clear the THUMB bit on qiAddress before comparing with known vtable entry
-    qiAddress &= ~THUMB_CODE;
+    *qiAddress &= ~THUMB_CODE;
 #endif
 
-    if (qiAddress != GetEEFuncEntryPoint(ManagedObjectWrapper_QueryInterface))
+    return TRUE;
+}
+
+BOOL ClrDataAccess::DACIsComWrappersCCW(CLRDATA_ADDRESS ccwPtr)
+{
+    TADDR vTableAddress = NULL;
+    TADDR qiAddress = NULL;
+    if (!DACGetComWrappersCCWVTableQIAddress(ccwPtr, &vTableAddress, &qiAddress))
     {
         return FALSE;
     }
 
-    return TRUE;
+    return qiAddress == GetEEFuncEntryPoint(ManagedObjectWrapper_QueryInterface);
 }
 
 TADDR ClrDataAccess::DACGetManagedObjectWrapperFromCCW(CLRDATA_ADDRESS ccwPtr)
@@ -4174,8 +4152,6 @@ HRESULT ClrDataAccess::DACTryGetComWrappersObjectFromCCW(CLRDATA_ADDRESS ccwPtr,
     }
 
     TADDR ccw = CLRDATA_ADDRESS_TO_TADDR(ccwPtr);
-    // Mask the "dispatch pointer" to get a double pointer to the ManagedObjectWrapper
-    TADDR managedObjectWrapperPtrPtr = ccw & InteropLib::ABI::DispatchThisPtrMask;
 
     // Return ManagedObjectWrapper as an OBJECTHANDLE. (The OBJECTHANDLE is guaranteed to live at offset 0).
     TADDR managedObjectWrapperPtr = DACGetManagedObjectWrapperFromCCW(ccwPtr);
@@ -4819,14 +4795,6 @@ HRESULT ClrDataAccess::GetObjectComWrappersData(CLRDATA_ADDRESS objAddr, CLRDATA
     }
 
     SOSDacEnter();
-    auto ComWrapperCallback = [](void *mocw, void *additionalData)
-    {
-        CQuickArrayList<CLRDATA_ADDRESS> *comWrappers = (CQuickArrayList<CLRDATA_ADDRESS>*)additionalData;
-
-        comWrappers->Push(TO_CDADDR(mocw));
-
-    };
-
     if (pNeeded != NULL)
     {
         *pNeeded = 0;
@@ -4845,11 +4813,24 @@ HRESULT ClrDataAccess::GetObjectComWrappersData(CLRDATA_ADDRESS objAddr, CLRDATA
         {
             if (rcw != NULL)
             {
-                *rcw = PTR_CDADDR(pInfo->m_externalComObjectContext);
+                *rcw = TO_TADDR(pInfo->m_externalComObjectContext);
             }
 
+            DPTR(NewHolder<ManagedObjectComWrapperByIdMap>) mapHolder(PTR_TO_MEMBER_TADDR(InteropSyncBlockInfo, pInfo, m_managedObjectComWrapperMap));
+            DPTR(ManagedObjectComWrapperByIdMap *)ppMap(PTR_TO_MEMBER_TADDR(NewHolder<ManagedObjectComWrapperByIdMap>, mapHolder, m_value));
+            DPTR(ManagedObjectComWrapperByIdMap) pMap(TO_TADDR(*ppMap));
+
             CQuickArrayList<CLRDATA_ADDRESS> comWrappers;
-            pInfo->IterateComWrappers(ComWrapperCallback, (void *)&comWrappers);
+            if (pMap != NULL)
+            {
+                ManagedObjectComWrapperByIdMap::Iterator iter = pMap->Begin();
+                while (iter != pMap->End())
+                {
+                    comWrappers.Push(TO_CDADDR(iter->Value()));
+                    ++iter;
+                
+                }
+            }
 
             if (pNeeded != NULL)
             {
@@ -4963,16 +4944,48 @@ HRESULT ClrDataAccess::IsComWrappersRCW(CLRDATA_ADDRESS rcw, BOOL *isComWrappers
     }
 
     SOSDacEnter();
-
-    PTR_ExternalObjectContext pEOC(TO_TADDR(rcw));
+    
     if (isComWrappersRCW != NULL)
     {
-        *isComWrappersRCW = pEOC->sentinel == ExternalObjectContextSentinelValue;
+        PTR_ExternalObjectContext pRCW(TO_TADDR(rcw));
+        BOOL stillValid = TRUE;
+        if(pRCW->SyncBlockIndex >= SyncBlockCache::s_pSyncBlockCache->m_SyncTableSize)
+        {
+            stillValid = FALSE;
+        }
+
+        PTR_SyncBlock pSyncBlk = NULL;
+        if (stillValid)
+        {
+            PTR_SyncTableEntry ste = PTR_SyncTableEntry(dac_cast<TADDR>(g_pSyncTable) + (sizeof(SyncTableEntry) * pRCW->SyncBlockIndex));
+            pSyncBlk = ste->m_SyncBlock;
+            if(pSyncBlk == NULL)
+            {
+                stillValid = FALSE;
+            }
+        }
+
+        PTR_InteropSyncBlockInfo pInfo = NULL;
+        if (stillValid)
+        {   
+            pInfo = pSyncBlk->GetInteropInfoNoCreate();
+            if(pInfo == NULL)
+            {
+                stillValid = FALSE;
+            }
+        }
+
+        if (stillValid)
+        {
+            stillValid = TO_TADDR(pInfo->m_externalComObjectContext) == PTR_HOST_TO_TADDR(pRCW);
+        }
+
+        *isComWrappersRCW = stillValid;
         hr = *isComWrappersRCW ? S_OK : S_FALSE; 
     }
 
     SOSDacLeave();
-    return hr;
+    return hr;    
 #else // FEATURE_COMWRAPPERS
     return E_NOTIMPL;
 #endif // FEATURE_COMWRAPPERS
@@ -4989,12 +5002,6 @@ HRESULT ClrDataAccess::GetComWrappersRCWData(CLRDATA_ADDRESS rcw, CLRDATA_ADDRES
     SOSDacEnter();
 
     PTR_ExternalObjectContext pEOC(TO_TADDR(rcw));
-    if (pEOC->sentinel != ExternalObjectContextSentinelValue)
-    {
-        // Not a ComWrappers RCW
-        hr = E_INVALIDARG;
-    }
-    
     if (identity != NULL)
     {
         *identity = PTR_CDADDR(pEOC->identity);

src/coreclr/src/inc/holder.h

@@ -115,6 +115,8 @@ struct AutoExpVisibleValue
 template <typename TYPE>
 class HolderBase
 {
+    friend class ClrDataAccess;
+
   protected:
     TYPE    m_value;
 
@@ -227,6 +229,7 @@ template
     >
 class BaseHolder : protected BASE
 {
+    friend class ClrDataAccess;
   protected:
     BOOL    m_acquired;      // Have we acquired the resource?
 
@@ -695,6 +698,7 @@ FORCEINLINE void SafeArrayDoNothing(SAFEARRAY* p)
 template <typename TYPE, void (*ACQUIREF)(TYPE), void (*RELEASEF)(TYPE)>
 class FunctionBase : protected HolderBase<TYPE>
 {
+    friend class ClrDataAccess;
   protected:
 
     FORCEINLINE FunctionBase(TYPE value)

src/coreclr/src/interop/comwrappers.hpp

@@ -117,10 +117,9 @@ class ManagedObjectWrapper
         /* [iid_is][out] */ _COM_Outptr_ void __RPC_FAR * __RPC_FAR * ppvObject);
     ULONG AddRef(void);
     ULONG Release(void);
-
 };
 
-// These Sentinel and Identity are used by the DAC, any changes to the layout must be updated on the DAC side (request.cpp)
+// The Target and _refCount fields are used by the DAC, any changes to the layout must be updated on the DAC side (request.cpp)
 static constexpr size_t DACTargetOffset = 0;
 static_assert(offsetof(ManagedObjectWrapper, Target) == DACTargetOffset, "Keep in sync with DAC interfaces");
 static constexpr size_t DACRefCountOffset = (4 * sizeof(intptr_t)) + (2 * sizeof(int32_t));