Repair rule permissions-checking bug reported by Tim Burgess 10-Feb-02:

the table(s) modified by the original query would get checked for the
type of write permission needed by a rule query.

diff --git a/src/backend/rewrite/rewriteHandler.c b/src/backend/rewrite/rewriteHandler.c
index 5ddee1ab194da0485ef5903db4ff415095843170..916c4d4c3f3bf812286355d04f4f7f77d12d0495 100644 (file)
--- a/src/backend/rewrite/rewriteHandler.c
+++ b/src/backend/rewrite/rewriteHandler.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.116 2003/01/17 02:01:16 tgl Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.117 2003/02/13 21:39:50 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -62,9 +62,11 @@ rewriteRuleAction(Query *parsetree,
 {
    int         current_varno,
                new_varno;
+   List       *main_rtable;
    int         rt_length;
    Query      *sub_action;
    Query     **sub_action_ptr;
+   List       *rt;
 
    /*
     * Make modifiable copies of rule action and qual (what we're passed
@@ -99,16 +101,31 @@ rewriteRuleAction(Query *parsetree,
     * Generate expanded rtable consisting of main parsetree's rtable plus
     * rule action's rtable; this becomes the complete rtable for the rule
     * action.  Some of the entries may be unused after we finish
-    * rewriting, but if we tried to clean those out we'd have a much
+    * rewriting, but if we tried to remove them we'd have a much
     * harder job to adjust RT indexes in the query's Vars.  It's OK to
     * have unused RT entries, since planner will ignore them.
     *
     * NOTE: because planner will destructively alter rtable, we must ensure
     * that rule action's rtable is separate and shares no substructure
     * with the main rtable.  Hence do a deep copy here.
+    *
+    * Also, we must disable write-access checking in all the RT entries
+    * copied from the main query.  This is safe since in fact the rule action
+    * won't write on them, and it's necessary because the rule action may
+    * have a different commandType than the main query, causing
+    * ExecCheckRTEPerms() to make an inappropriate check.  The read-access
+    * checks can be left enabled, although they're probably redundant.
     */
-   sub_action->rtable = nconc((List *) copyObject(parsetree->rtable),
-                              sub_action->rtable);
+   main_rtable = (List *) copyObject(parsetree->rtable);
+
+   foreach(rt, main_rtable)
+   {
+       RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt);
+
+       rte->checkForWrite = false;
+   }
+
+   sub_action->rtable = nconc(main_rtable, sub_action->rtable);
 
    /*
     * Each rule action's jointree should be the main parsetree's jointree