MDEV-14857: problem with 10.2.11 server crashing when executing stored procedure

Counter for select numbering made stored with the statement (before was global)
So now it does have always accurate value which does not depend on
interruption of statement prepare by errors like lack of table in
a view definition.

1 files changed, 7 insertions, 28 deletions

diff --git a/sql/sp_head.cc b/sql/sp_head.cc
index eceebd1d13f..8bf78d97670 100644
--- a/sql/sp_head.cc
+++ b/sql/sp_head.cc
@@ -597,7 +597,7 @@ sp_head::sp_head()
    m_flags(0),
    m_sp_cache_version(0),
    m_creation_ctx(0),
-   unsafe_flags(0), m_select_number(1),
+   unsafe_flags(0),
    m_recursion_level(0),
    m_next_cached_sp(0),
    m_cont_level(0)
@@ -840,7 +840,7 @@ sp_head::~sp_head()
     thd->lex->sphead= NULL;
     lex_end(thd->lex);
     delete thd->lex;
-    thd->lex= lex;
+    thd->lex= thd->stmt_lex= lex;
   }
 
   my_hash_free(&m_sptabs);
@@ -1121,7 +1121,7 @@ sp_head::execute(THD *thd, bool merge_da_on_success)
               backup_arena;
   query_id_t old_query_id;
   TABLE *old_derived_tables;
-  LEX *old_lex;
+  LEX *old_lex, *old_stmt_lex;
   Item_change_list old_change_list;
   String old_packet;
   uint old_server_status;
@@ -1136,19 +1136,6 @@ sp_head::execute(THD *thd, bool merge_da_on_success)
   if (check_stack_overrun(thd, 7 * STACK_MIN_SIZE, (uchar*)&old_packet))
     DBUG_RETURN(TRUE);
 
-  /*
-     Normally the counter is not reset between parsing and first execution,
-     but it is possible in case of error to have parsing on one CALL and
-     first execution (where VIEW will be parsed and added). So we store the
-     counter after parsing and restore it before execution just to avoid
-     repeating SELECT numbers.
-
-     Other problem is that it can be more SELECTs parsed in case of fixing
-     error causes previous interruption of the SP. So it is save not just
-     assign old value but add it.
-   */
-  thd->select_number+= m_select_number;
-
   /* init per-instruction memroot */
   init_sql_alloc(&execute_mem_root, MEM_ROOT_BLOCK_SIZE, 0, MYF(0));
 
@@ -1237,6 +1224,7 @@ sp_head::execute(THD *thd, bool merge_da_on_success)
     do it in each instruction
   */
   old_lex= thd->lex;
+  old_stmt_lex= thd->stmt_lex;
   /*
     We should also save Item tree change list to avoid rollback something
     too early in the calling query.
@@ -1384,6 +1372,7 @@ sp_head::execute(THD *thd, bool merge_da_on_success)
   DBUG_ASSERT(thd->change_list.is_empty());
   old_change_list.move_elements_to(&thd->change_list);
   thd->lex= old_lex;
+  thd->stmt_lex= old_stmt_lex;
   thd->set_query_id(old_query_id);
   DBUG_ASSERT(!thd->derived_tables);
   thd->derived_tables= old_derived_tables;
@@ -1482,16 +1471,6 @@ sp_head::execute(THD *thd, bool merge_da_on_success)
                m_recursion_level + 1));
   m_first_instance->m_first_free_instance= this;
 
-  /*
-     This execution of the SP was aborted with an error (e.g. "Table not
-     found").  However it might still have consumed some numbers from the
-     thd->select_number counter.  The next sp->exec() call must not use the
-     consumed numbers, so we remember the first free number (We know that
-     nobody will use it as this execution has stopped with an error).
-   */
-  if (err_status)
-    set_select_number(thd->select_number);
-
   DBUG_RETURN(err_status);
 }
 
@@ -2228,7 +2207,7 @@ sp_head::reset_lex(THD *thd)
   if (sublex == 0)
     DBUG_RETURN(TRUE);
 
-  thd->lex= sublex;
+  thd->lex= thd->stmt_lex= sublex;
   (void)m_lex.push_front(oldlex);
 
   /* Reset most stuff. */
@@ -2974,7 +2953,7 @@ sp_lex_keeper::reset_lex_and_exec_core(THD *thd, uint *nextp,
     We should not save old value since it is saved/restored in
     sp_head::execute() when we are entering/leaving routine.
   */
-  thd->lex= m_lex;
+  thd->lex= thd->stmt_lex= m_lex;
 
   thd->set_query_id(next_query_id());