Avoid infinite loop in case of heap corruption (#70759)

Co-authored-by: NJuan Hoyos <juan.hoyos@microsoft.com>
Co-authored-by: NNoah Falk <noahfalk@users.noreply.github.com>

src/coreclr/debug/daccess/dacdbiimpl.cpp

@@ -6450,7 +6450,7 @@ HRESULT DacHeapWalker::MoveToNextObject()
 
 bool DacHeapWalker::GetSize(TADDR tMT, size_t &size)
 {
-    // With heap corruption, it's entierly possible that the MethodTable
+    // With heap corruption, it's entirely possible that the MethodTable
     // we get is bad.  This could cause exceptions, which we will catch
     // and return false.  This causes the heapwalker to move to the next
     // segment.
@@ -6478,6 +6478,12 @@ bool DacHeapWalker::GetSize(TADDR tMT, size_t &size)
             size = AlignLarge(size);
         else
             size = Align(size);
+
+        // If size == 0, it means we have a heap corruption and
+        // we will stuck in an infinite loop, so better fail the call now.
+        ret &= (0 < size);
+        // Also guard for cases where the size reported is too large and exceeds the high allocation mark.
+        ret &= ((tMT + size) <= mHeaps[mCurrHeap].Segments[mCurrSeg].End);
     }
     EX_CATCH
     {