Fixed bug #7860 : Crash potentially caused by BETWEEN Operator

Author: hvlad

src/jrd/recsrc/ConditionalStream.cpp

@@ -53,9 +53,9 @@ void ConditionalStream::open(thread_db* tdbb) const
 	jrd_req* const request = tdbb->getRequest();
 	Impure* const impure = request->getImpure<Impure>(m_impure);
 
-	impure->irsb_flags = irsb_open;
-
 	impure->irsb_next = m_boolean->execute(tdbb, request) ? m_first : m_second;
+
+	impure->irsb_flags = irsb_open;
 	impure->irsb_next->open(tdbb);
 }
 
@@ -71,7 +71,8 @@ void ConditionalStream::close(thread_db* tdbb) const
 	{
 		impure->irsb_flags &= ~irsb_open;
 
-		impure->irsb_next->close(tdbb);
+		if (impure->irsb_next)
+			impure->irsb_next->close(tdbb);
 	}
 }