From ced64f85823c7a9dcd6b9f952c136278567fa9f6 Mon Sep 17 00:00:00 2001
From: "tsmith@ramayana.hindu.god" <>
Date: Wed, 10 Oct 2007 14:00:57 -0600
Subject: [PATCH] Bug #31517: Potential crash due to access of NULL thd in
 mark_transaction_to_rollback()

Introduced in mark_transaction_to_rollback(), part of fix for bug 24989;
fix is to check thd for NULL before using it.
---
 sql/sql_class.cc | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/sql/sql_class.cc b/sql/sql_class.cc
index b67f63778dc..4a98a044e25 100644
--- a/sql/sql_class.cc
+++ b/sql/sql_class.cc
@@ -2241,8 +2241,11 @@ void THD::restore_sub_statement_state(Sub_statement_state *backup)
 
 void mark_transaction_to_rollback(THD *thd, bool all)
 {
-  thd->is_fatal_sub_stmt_error= TRUE;
-  thd->transaction_rollback_request= all;
+  if (thd)
+  {
+    thd->is_fatal_sub_stmt_error= TRUE;
+    thd->transaction_rollback_request= all;
+  }
 }
 /***************************************************************************
   Handling of XA id cacheing