Fix contract violation in debugger func eval (#56933)

`DebuggerEval::DebuggerEval` is called from `Debugger::FuncEvalSetup` which is a NOTHROW function. As the `GetInteropSafeExecutableHeap` and associated `Alloc` functions can fail with an OOM, move the allocation out of the constructor to the caller where we can safely return `E_OUTOFMEMORY`.

This contract violation prevents debugging on chk and debug builds of the runtime.

Fixes #54504

diff --git a/src/coreclr/debug/ee/debugger.cpp b/src/coreclr/debug/ee/debugger.cpp
index 81965f1..23d0c12 100644 (file)
--- a/src/coreclr/debug/ee/debugger.cpp
+++ b/src/coreclr/debug/ee/debugger.cpp
@@ -1314,22 +1314,22 @@ ULONG DebuggerMethodInfoTable::CheckDmiTable(void)
 //      pContext - The context to return to when done with this eval.
 //      pEvalInfo - Contains all the important information, such as parameters, type args, method.
 //      fInException - TRUE if the thread for the eval is currently in an exception notification.
+//      bpInfoSegmentRX - bpInfoSegmentRX is an InteropSafe allocation allocated by the caller.
+//                        (Caller allocated as there is no way to fail the allocation without
+//                        throwing, and this function is called in a NOTHROW region)
 //
-DebuggerEval::DebuggerEval(CONTEXT * pContext, DebuggerIPCE_FuncEvalInfo * pEvalInfo, bool fInException)
+DebuggerEval::DebuggerEval(CONTEXT * pContext, DebuggerIPCE_FuncEvalInfo * pEvalInfo, bool fInException, DebuggerEvalBreakpointInfoSegment* bpInfoSegmentRX)
 {
     WRAPPER_NO_CONTRACT;
 
-    // Allocate the breakpoint instruction info in executable memory.
-    void *bpInfoSegmentRX = g_pDebugger->GetInteropSafeExecutableHeap()->Alloc(sizeof(DebuggerEvalBreakpointInfoSegment));
-
 #if !defined(DBI_COMPILE) && !defined(DACCESS_COMPILE) && defined(HOST_OSX) && defined(HOST_ARM64)
-    ExecutableWriterHolder<DebuggerEvalBreakpointInfoSegment> bpInfoSegmentWriterHolder((DebuggerEvalBreakpointInfoSegment*)bpInfoSegmentRX, sizeof(DebuggerEvalBreakpointInfoSegment));
+    ExecutableWriterHolder<DebuggerEvalBreakpointInfoSegment> bpInfoSegmentWriterHolder(bpInfoSegmentRX, sizeof(DebuggerEvalBreakpointInfoSegment));
     DebuggerEvalBreakpointInfoSegment *bpInfoSegmentRW = bpInfoSegmentWriterHolder.GetRW();
 #else // !DBI_COMPILE && !DACCESS_COMPILE && HOST_OSX && HOST_ARM64
-    DebuggerEvalBreakpointInfoSegment *bpInfoSegmentRW = (DebuggerEvalBreakpointInfoSegment*)bpInfoSegmentRX;
+    DebuggerEvalBreakpointInfoSegment *bpInfoSegmentRW = bpInfoSegmentRX;
 #endif // !DBI_COMPILE && !DACCESS_COMPILE && HOST_OSX && HOST_ARM64
     new (bpInfoSegmentRW) DebuggerEvalBreakpointInfoSegment(this);
-    m_bpInfoSegment = (DebuggerEvalBreakpointInfoSegment*)bpInfoSegmentRX;
+    m_bpInfoSegment = bpInfoSegmentRX;
 
     // This must be non-zero so that the saved opcode is non-zero, and on IA64 we want it to be 0x16
     // so that we can have a breakpoint instruction in any slot in the bundle.
@@ -15139,9 +15139,22 @@ HRESULT Debugger::FuncEvalSetup(DebuggerIPCE_FuncEvalInfo *pEvalInfo,
         return CORDBG_E_FUNC_EVAL_BAD_START_POINT;
     }
 
+    // Allocate the breakpoint instruction info for the debugger info in in executable memory.
+    DebuggerHeap *pHeap = g_pDebugger->GetInteropSafeExecutableHeap_NoThrow();
+    if (pHeap == NULL)
+    {
+        return E_OUTOFMEMORY;
+    }
+
+    DebuggerEvalBreakpointInfoSegment *bpInfoSegmentRX = (DebuggerEvalBreakpointInfoSegment*)pHeap->Alloc(sizeof(DebuggerEvalBreakpointInfoSegment));
+    if (bpInfoSegmentRX == NULL)
+    {
+        return E_OUTOFMEMORY;
+    }
+
     // Create a DebuggerEval to hold info about this eval while its in progress. Constructor copies the thread's
     // CONTEXT.
-    DebuggerEval *pDE = new (interopsafe, nothrow) DebuggerEval(filterContext, pEvalInfo, fInException);
+    DebuggerEval *pDE = new (interopsafe, nothrow) DebuggerEval(filterContext, pEvalInfo, fInException, bpInfoSegmentRX);
 
     if (pDE == NULL)
     {

diff --git a/src/coreclr/debug/ee/debugger.h b/src/coreclr/debug/ee/debugger.h
index 4f8b13c..8ac2aef 100644 (file)
--- a/src/coreclr/debug/ee/debugger.h
+++ b/src/coreclr/debug/ee/debugger.h
@@ -3452,7 +3452,7 @@ public:
     TypeHandle                         m_ownerTypeHandle;
     DebuggerEvalBreakpointInfoSegment* m_bpInfoSegment;
 
-    DebuggerEval(T_CONTEXT * pContext, DebuggerIPCE_FuncEvalInfo * pEvalInfo, bool fInException);
+    DebuggerEval(T_CONTEXT * pContext, DebuggerIPCE_FuncEvalInfo * pEvalInfo, bool fInException, DebuggerEvalBreakpointInfoSegment* bpInfoSegmentRX);
 
     bool Init()
     {