Add EntryPointFilter option (#23054)

* Add EntryPointFilter

diff --git a/src/vm/clrex.h b/src/vm/clrex.h
index a38f3a3..c1cd80d 100644 (file)
--- a/src/vm/clrex.h
+++ b/src/vm/clrex.h
@@ -844,7 +844,7 @@ LONG CLRNoCatchHandler(EXCEPTION_POINTERS* pExceptionInfo, PVOID pv);
         }                               \
         PAL_ENDTRY                      \
     }                                   \
-    PAL_EXCEPT_FILTER(CLRNoCatchHandler) \
+    PAL_EXCEPT_FILTER(EntryPointFilter) \
     {                                   \
     }                                   \
     PAL_ENDTRY

diff --git a/src/vm/corhost.cpp b/src/vm/corhost.cpp
index 1a376f0..e02b514 100644 (file)
--- a/src/vm/corhost.cpp
+++ b/src/vm/corhost.cpp
@@ -740,6 +740,12 @@ HRESULT CorHost2::_CreateAppDomain(
         {
             pwzAppNiPaths = pPropertyValues[i];
         }
+        else
+        if (wcscmp(pPropertyNames[i], W("USE_ENTRYPOINT_FILTER")) == 0)
+        {
+            extern void ParseUseEntryPointFilter(LPCWSTR value);
+            ParseUseEntryPointFilter(pPropertyValues[i]);
+        }
 #ifdef FEATURE_COMINTEROP
         else
         if (wcscmp(pPropertyNames[i], W("APP_LOCAL_WINMETADATA")) == 0)

diff --git a/src/vm/excep.cpp b/src/vm/excep.cpp
index 8f5cc08..26003f0 100644 (file)
--- a/src/vm/excep.cpp
+++ b/src/vm/excep.cpp
@@ -4822,20 +4822,6 @@ LONG InternalUnhandledExceptionFilter_Worker(
     //
     if (pThread && pThread->HasThreadStateNC(Thread::TSNC_ProcessedUnhandledException))
     {
-        // This assert shouldnt be hit in CoreCLR since:
-        //
-        // 1) It has no concept of managed entry point that is invoked by the shim. You can
-        //    only run managed code via hosting APIs that will run code in non-default domains.
-        //
-        // 2) Managed threads cannot be created in DefaultDomain since no user code executes
-        //    in default domain.
-        //
-        // So, if this is hit, something is not right!
-        if (pThread->HasThreadStateNC(Thread::TSNC_ProcessedUnhandledException))
-        {
-            _ASSERTE(!"How come a thread with TSNC_ProcessedUnhandledException state entered the UEF on CoreCLR?");
-        }
-
         LOG((LF_EH, LL_INFO100, "InternalUnhandledExceptionFilter_Worker: have already processed unhandled exception for this thread.\n"));
         return EXCEPTION_CONTINUE_SEARCH;
     }
@@ -5152,10 +5138,20 @@ LONG InternalUnhandledExceptionFilter(
 
 } // LONG InternalUnhandledExceptionFilter()
 
+static bool s_useEntryPointFilter = false;
+
+void ParseUseEntryPointFilter(LPCWSTR value)
+{
+#ifdef PLATFORM_WINDOWS // This feature has only been tested on Windows, keep it disabled on other platforms
+    // set s_useEntryPointFilter true if value != "0"
+    if (value && (_wcsicmp(value, W("0")) != 0))
+    {
+        s_useEntryPointFilter = true;
+    }
+#endif
+}
+
 // This filter is used to trigger unhandled exception processing for the entrypoint thread
-// incase an exception goes unhandled from it. This makes us independent of the OS
-// UEF mechanism to invoke our registered UEF to trigger CLR specific unhandled exception 
-// processing since that can be skipped if another UEF registered over ours and not chain back.
 LONG EntryPointFilter(PEXCEPTION_POINTERS pExceptionInfo, PVOID _pData)
 {
     CONTRACTL
@@ -5168,20 +5164,38 @@ LONG EntryPointFilter(PEXCEPTION_POINTERS pExceptionInfo, PVOID _pData)
 
     LONG ret = -1;
 
-    // Invoke the UEF worker to perform unhandled exception processing
-    ret = InternalUnhandledExceptionFilter_Worker (pExceptionInfo);
+    ret = CLRNoCatchHandler(pExceptionInfo, _pData);
+
+    if (ret != EXCEPTION_CONTINUE_SEARCH)
+    {
+        return ret;
+    }
+
+    if (!s_useEntryPointFilter)
+    {
+        return EXCEPTION_CONTINUE_SEARCH;
+    }
 
     Thread* pThread = GetThread();
-    if (pThread)
+    if (pThread && !GetThread()->HasThreadStateNC(Thread::TSNC_ProcessedUnhandledException))
     {
+        // Invoke the UEF worker to perform unhandled exception processing
+        ret = InternalUnhandledExceptionFilter_Worker (pExceptionInfo);
+
         // Set the flag that we have done unhandled exception processing for this thread
         // so that we dont duplicate the effort in the UEF.
         //
         // For details on this flag, refer to threads.h.
         LOG((LF_EH, LL_INFO100, "EntryPointFilter: setting TSNC_ProcessedUnhandledException\n"));
         pThread->SetThreadStateNC(Thread::TSNC_ProcessedUnhandledException);
+
+        if (ret == EXCEPTION_EXECUTE_HANDLER)
+        {
+            // Do not swallow the exception, we just want to log it
+            return EXCEPTION_CONTINUE_SEARCH;
+        }
     }
-    
+
     return ret;
 }