Fixed BUG#14233: Crash after tampering with the mysql.proc table

  Post-review version. Some minor review fixes, but also changed the way
  some errors are handled: Don't return specific parse errors; instead
  always use the more general "table corrupt" error (amended accordingly).


mysql-test/r/sp-destruct.result:
  Updated results.
mysql-test/r/sp-error.result:
  Updated for fully qualified name in "no return" error message.
mysql-test/t/sp-destruct.test:
  Adopted the more consistent error handling for a corrupted mysql.proc table.
  (No more "parse error" et al).
sql/share/errmsg.txt:
  Changed ER_SP_PROC_TABLE_CORRUPT to be more explicit.
sql/sp.cc:
  Review fixes.
  Changed the handling of parse errors, and added the routine name to the "table corrupt" error message.
sql/sql_base.cc:
  Review changes: Change error tests and added comments.
sql/sql_parse.cc:
  Mored ER_SP_NORETURN test of functions to sql_yacc.yy for more general error handling.
sql/sql_yacc.yy:
  Mored ER_SP_NORETURN test of functions from sql_parse.cc for more general error handling.

mysql-test/r/sp-destruct.result

@@ -11,11 +11,11 @@ create table t1 (id int);
 create trigger t1_ai after insert on t1 for each row call bug14233();
 alter table mysql.proc drop type;
 call bug14233();
-ERROR HY000: The table mysql.proc is missing, corrupt, or contains bad data (internal code -5)
+ERROR HY000: Failed to load routine test.bug14233. The table mysql.proc is missing, corrupt, or contains bad data (internal code -5)
 create view v1 as select bug14233_f();
-ERROR HY000: The table mysql.proc is missing, corrupt, or contains bad data (internal code -5)
+ERROR HY000: Failed to load routine test.bug14233_f. The table mysql.proc is missing, corrupt, or contains bad data (internal code -5)
 insert into t1 values (0);
-ERROR HY000: The table mysql.proc is missing, corrupt, or contains bad data (internal code -5)
+ERROR HY000: Failed to load routine test.bug14233. The table mysql.proc is missing, corrupt, or contains bad data (internal code -5)
 flush table mysql.proc;
 call bug14233();
 ERROR HY000: Incorrect information in file: './mysql/proc.frm'
@@ -59,21 +59,19 @@ values
 'root@localhost', NOW() , '0000-00-00 00:00:00', '', ''
 );
 select bug14233_1();
-ERROR 0A000: Not allowed to return a result set from a function
+ERROR HY000: Failed to load routine test.bug14233_1. The table mysql.proc is missing, corrupt, or contains bad data (internal code -6)
 create view v1 as select bug14233_1();
-ERROR 0A000: Not allowed to return a result set from a function
+ERROR HY000: Failed to load routine test.bug14233_1. The table mysql.proc is missing, corrupt, or contains bad data (internal code -6)
 select bug14233_2();
-ERROR 2F005: FUNCTION bug14233_2 ended without RETURN
+ERROR HY000: Failed to load routine test.bug14233_2. The table mysql.proc is missing, corrupt, or contains bad data (internal code -6)
 create view v1 as select bug14233_2();
-select * from v1;
-ERROR 2F005: FUNCTION bug14233_2 ended without RETURN
+ERROR HY000: Failed to load routine test.bug14233_2. The table mysql.proc is missing, corrupt, or contains bad data (internal code -6)
 call bug14233_3();
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'wpsj sa ^#!@ ' at line 3
+ERROR HY000: Failed to load routine test.bug14233_3. The table mysql.proc is missing, corrupt, or contains bad data (internal code -6)
 drop trigger t1_ai;
 create trigger t1_ai after insert on t1 for each row call bug14233_3();
 insert into t1 values (0);
-ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'wpsj sa ^#!@ ' at line 3
+ERROR HY000: Failed to load routine test.bug14233_3. The table mysql.proc is missing, corrupt, or contains bad data (internal code -6)
 delete from mysql.proc where name like 'bug14233%';
 drop trigger t1_ai;
 drop table t1;
-drop view v1;

mysql-test/r/sp-error.result

@@ -124,7 +124,7 @@ begin
 declare x int;
 set x = val+3;
 end|
-ERROR 42000: No RETURN found in FUNCTION f
+ERROR 42000: No RETURN found in FUNCTION test.f
 create function f(val int) returns int
 begin
 declare x int;

mysql-test/t/sp-destruct.test

@@ -101,26 +101,24 @@ values
   'root@localhost', NOW() , '0000-00-00 00:00:00', '', ''
 );
 
---error ER_SP_NO_RETSET
+--error ER_SP_PROC_TABLE_CORRUPT
 select bug14233_1();
---error ER_SP_NO_RETSET
+--error ER_SP_PROC_TABLE_CORRUPT
 create view v1 as select bug14233_1();
 
---error ER_SP_NORETURNEND
+--error ER_SP_PROC_TABLE_CORRUPT
 select bug14233_2();
+--error ER_SP_PROC_TABLE_CORRUPT
 create view v1 as select bug14233_2();
---error ER_SP_NORETURNEND
-select * from v1;
 
---error ER_PARSE_ERROR
+--error ER_SP_PROC_TABLE_CORRUPT
 call bug14233_3();
 drop trigger t1_ai;
 create trigger t1_ai after insert on t1 for each row call bug14233_3();
---error ER_PARSE_ERROR
+--error ER_SP_PROC_TABLE_CORRUPT
 insert into t1 values (0);
 
 # Clean-up
 delete from mysql.proc where name like 'bug14233%';
 drop trigger t1_ai;
 drop table t1;
-drop view v1;

sql/share/errmsg.txt

@@ -5422,4 +5422,4 @@ ER_NO_REFERENCED_ROW_2 23000
 ER_SP_BAD_VAR_SHADOW 42000
 	eng "Variable '%-.64s' must be quoted with `...`, or renamed"
 ER_SP_PROC_TABLE_CORRUPT
-	eng "The table mysql.proc is missing, corrupt, or contains bad data (internal code %d)"
+	eng "Failed to load routine %s. The table mysql.proc is missing, corrupt, or contains bad data (internal code %d)"

sql/sp.cc

@@ -1420,8 +1420,8 @@ static void sp_update_stmt_used_routines(THD *thd, LEX *lex, SQL_LIST *src)
     Instead this fact will be discovered during query execution.
 
   RETURN VALUE
-     0 - success
-    -x - failure (error code, like SP_PARSE_ERROR et al)
+     0     - success
+     non-0 - failure
 */
 
 static int
@@ -1430,7 +1430,7 @@ sp_cache_routines_and_add_tables_aux(THD *thd, LEX *lex,
                                      bool first_no_prelock, bool *tabs_changed)
 {
   int ret= 0;
-  bool result= FALSE;
+  int tabschnd= 0;              /* Set if tables changed */
   bool first= TRUE;
   DBUG_ENTER("sp_cache_routines_and_add_tables_aux");
 
@@ -1478,11 +1478,21 @@ sp_cache_routines_and_add_tables_aux(THD *thd, LEX *lex,
         /* Fall through */
       default:
         /*
-          In some cases no error has been set (e.g. get field failed,
-          when the proc table has been tampered with).
-         */
-        if (! thd->net.report_error)
-          my_error(ER_SP_PROC_TABLE_CORRUPT, MYF(0), ret);
+          Any error when loading an existing routine is either some problem
+          with the mysql.proc table, or a parse error because the contents
+          has been tampered with (in which case we clear that error).
+        */
+        if (ret == SP_PARSE_ERROR)
+          thd->clear_error();
+        if (!thd->net.report_error)
+        {
+          char n[NAME_LEN*2+2];
+
+          /* m_qname.str is not always \0 terminated */
+          memcpy(n, name.m_qname.str, name.m_qname.length);
+          n[name.m_qname.length]= '\0';
+          my_error(ER_SP_PROC_TABLE_CORRUPT, MYF(0), n, ret);
+        }
         break;
       }
       delete newlex;
@@ -1493,13 +1503,14 @@ sp_cache_routines_and_add_tables_aux(THD *thd, LEX *lex,
       if (!(first && first_no_prelock))
       {
         sp_update_stmt_used_routines(thd, lex, &sp->m_sroutines);
-        result|= sp->add_used_tables_to_table_list(thd, &lex->query_tables_last);
+        tabschnd|=
+          sp->add_used_tables_to_table_list(thd, &lex->query_tables_last);
       }
     }
     first= FALSE;
   }
-  if (tabs_changed)
-    *tabs_changed= result;
+  if (tabs_changed)             /* it can be NULL  */
+    *tabs_changed= tabschnd;
   DBUG_RETURN(ret);
 }
 
@@ -1518,8 +1529,8 @@ sp_cache_routines_and_add_tables_aux(THD *thd, LEX *lex,
       tabs_changed     - Set to TRUE some tables were added, FALSE otherwise
                          
   RETURN VALUE
-     0 - success
-    -x - failure (error code, like SP_PARSE_ERROR et al)
+     0     - success
+     non-0 - failure
 */
 
 int
@@ -1544,8 +1555,8 @@ sp_cache_routines_and_add_tables(THD *thd, LEX *lex, bool first_no_prelock,
       aux_lex - LEX representing view
                          
   RETURN VALUE
-     0 - success
-    -x - failure (error code, like SP_PARSE_ERROR et al)
+     0     - success
+     non-0 - failure
 */
 
 int
@@ -1572,8 +1583,8 @@ sp_cache_routines_and_add_tables_for_view(THD *thd, LEX *lex, LEX *aux_lex)
       triggers - triggers of the table
 
   RETURN VALUE
-     0 - success
-    -x - failure (error code, like SP_PARSE_ERROR et al)
+     0     - success
+     non-0 - failure
 */
 
 int

sql/sql_base.cc

@@ -1986,9 +1986,14 @@ int open_tables(THD *thd, TABLE_LIST **start, uint *counter, uint flags)
 
     if (sp_cache_routines_and_add_tables(thd, thd->lex,
                                          first_no_prelocking,
-                                         &tabs_changed) < 0)
+                                         &tabs_changed))
     {
-      result= -1;               // Fatal error
+      /*
+        Serious error during reading stored routines from mysql.proc table.
+        Something's wrong with the table or its contents, and an error has
+        been emitted; we must abort.
+      */
+      result= -1;
       goto err;
     }
     else if ((tabs_changed || *start) && need_prelocking)
@@ -2117,9 +2122,14 @@ int open_tables(THD *thd, TABLE_LIST **start, uint *counter, uint flags)
         if (!query_tables_last_own)
           query_tables_last_own= thd->lex->query_tables_last;
         if (sp_cache_routines_and_add_tables_for_triggers(thd, thd->lex,
-                                                   tables->table->triggers) < 0)
+                                                   tables->table->triggers))
         {
-          result= -1;               // Fatal error
+          /*
+            Serious error during reading stored routines from mysql.proc table.
+            Something's wrong with the table or its contents, and an error has
+            been emitted; we must abort.
+          */
+          result= -1;
           goto err;
         }
       }
@@ -2143,9 +2153,14 @@ int open_tables(THD *thd, TABLE_LIST **start, uint *counter, uint flags)
       if (!query_tables_last_own)
         query_tables_last_own= thd->lex->query_tables_last;
       if (sp_cache_routines_and_add_tables_for_view(thd, thd->lex,
-                                                    tables->view) < 0)
+                                                    tables->view))
       {
-        result= -1;               // Fatal error
+        /*
+          Serious error during reading stored routines from mysql.proc table.
+          Something's wrong with the table or its contents, and an error has
+          been emitted; we must abort.
+        */
+        result= -1;
         goto err;
       }
     }

sql/sql_parse.cc

@@ -4111,14 +4111,6 @@ mysql_execute_command(THD *thd)
       }
     }
 #endif
-    if (lex->sphead->m_type == TYPE_ENUM_FUNCTION &&
-	!(lex->sphead->m_flags & sp_head::HAS_RETURN))
-    {
-      my_error(ER_SP_NORETURN, MYF(0), name);
-      delete lex->sphead;
-      lex->sphead= 0;
-      goto error;
-    }
 
     /*
       We need to copy name and db in order to use them for

sql/sql_yacc.yy

@@ -1475,6 +1475,11 @@ create_function_tail:
 	      YYABORT;
 	    lex->sql_command= SQLCOM_CREATE_SPFUNCTION;
 	    sp->init_strings(YYTHD, lex, lex->spname);
+            if (!(sp->m_flags & sp_head::HAS_RETURN))
+            {
+              my_error(ER_SP_NORETURN, MYF(0), sp->m_qname.str);
+              YYABORT;
+            }
 	    /* Restore flag if it was cleared above */
 	    if (sp->m_old_cmq)
 	      YYTHD->client_capabilities |= CLIENT_MULTI_QUERIES;