bk commit into 5.0 tree (evgen:1.1984) BUG#15538

[eugene]

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ChangeSet
  1.1984 05/12/21 23:31:50 evgen@stripped +1 -0
  Fix bug#15538 unchecked table absense caused server crash.
  
  Absense of table in left part of LEFT/RIGHT join wasn't checked before
  namespace processing. Which leads to NULL dereferencing and server crash.
  
  Modified rules: 
  "table_ref LEFT opt_outer JOIN_SYM table_ref" and "table_ref RIGHT opt_outer 
  JOIN_SYM table_ref"
  NULL check moved just before any rule handling is performed.

  sql/sql_yacc.yy
    1.446 05/12/21 23:27:57 evgen@stripped +2 -2
    Fix bug#15538 unchecked table absense caused server crash.
    Modified rules: 
    "table_ref LEFT opt_outer JOIN_SYM table_ref" and "table_ref RIGHT opt_outer 
    JOIN_SYM table_ref"
    NULL check moved just before any rule handling is performed.

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	evgen
# Host:	moonbone.local
# Root:	/work/15538-bug-5.0-mysql

--- 1.445/sql/sql_yacc.yy	2005-12-11 10:30:53 +03:00
+++ 1.446/sql/sql_yacc.yy	2005-12-21 23:27:57 +03:00
@@ -5248,13 +5248,13 @@
 	| table_ref LEFT opt_outer JOIN_SYM table_ref
           ON
           {
+            YYERROR_UNLESS($1 && $5);
             /* Change the current name resolution context to a local context. */
             if (push_new_name_resolution_context(YYTHD, $1, $5))
               YYABORT;
           }
           expr
 	  {
-            YYERROR_UNLESS($1 && $5);
             add_join_on($5,$8);
             Lex->pop_context();
             $5->outer_join|=JOIN_TYPE_LEFT;
@@ -5279,6 +5279,7 @@
 	| table_ref RIGHT opt_outer JOIN_SYM table_ref
           ON
           {
+            YYERROR_UNLESS($1 && $5);
             /* Change the current name resolution context to a local context. */
             if (push_new_name_resolution_context(YYTHD, $1, $5))
               YYABORT;
@@ -5286,7 +5287,6 @@
           expr
           {
 	    LEX *lex= Lex;
-            YYERROR_UNLESS($1 && $5);
             if (!($$= lex->current_select->convert_right_join()))
               YYABORT;
             add_join_on($$, $8);