Fix error case for CREATE ROLE ... IN ROLE.

CreateRole() was passing a Value node, not a RoleSpec node, for the
newly-created role name when adding the role as a member of existing
roles for the IN ROLE syntax.

This mistake went unnoticed because the node in question is used only
for error messages and is not accessed on non-error paths.

In older pg versions (such as 9.5 where this was found), this results
in an "unexpected node type" error in place of the real error. That
node type check was removed at some point, after which the code would
accidentally fail to fail on 64-bit platforms (on which accessing the
Value node as if it were a RoleSpec would be mostly harmless) or give
an "unexpected role type" error on 32-bit platforms.

Fix the code to pass the correct node type, and add an lfirst_node
assertion just in case.

Per report on irc from user m1chelangelo.

Backpatch all the way, because this error has been around for a long
time.

diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index 2961ccb8ef3d68561d09ae5968d7a256eb25b1ce..ccacf2d0d1fde841cf44bccc1410b77f46ddb430 100644 (file)
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -421,19 +421,31 @@ CreateRole(CreateRoleStmt *stmt)
    /*
     * Add the new role to the specified existing roles.
     */
-   foreach(item, addroleto)
+   if (addroleto)
    {
-       RoleSpec   *oldrole = lfirst(item);
-       HeapTuple   oldroletup = get_rolespec_tuple((Node *) oldrole);
-       Oid         oldroleid = HeapTupleGetOid(oldroletup);
-       char       *oldrolename = NameStr(((Form_pg_authid) GETSTRUCT(oldroletup))->rolname);
-
-       AddRoleMems(oldrolename, oldroleid,
-                   list_make1(makeString(stmt->role)),
-                   list_make1_oid(roleid),
-                   GetUserId(), false);
+       RoleSpec   *thisrole = makeNode(RoleSpec);
+       List       *thisrole_list = list_make1(thisrole);
+       List       *thisrole_oidlist = list_make1_oid(roleid);
+
+       thisrole->roletype = ROLESPEC_CSTRING;
+       thisrole->rolename = stmt->role;
+       thisrole->location = -1;
 
-       ReleaseSysCache(oldroletup);
+       foreach(item, addroleto)
+       {
+           RoleSpec   *oldrole = lfirst(item);
+           HeapTuple   oldroletup = get_rolespec_tuple((Node *) oldrole);
+           Form_pg_authid oldroleform = (Form_pg_authid) GETSTRUCT(oldroletup);
+           Oid         oldroleid = HeapTupleGetOid(oldroletup);
+           char       *oldrolename = NameStr(oldroleform->rolname);
+
+           AddRoleMems(oldrolename, oldroleid,
+                       thisrole_list,
+                       thisrole_oidlist,
+                       GetUserId(), false);
+
+           ReleaseSysCache(oldroletup);
+       }
    }
 
    /*
@@ -1423,7 +1435,7 @@ AddRoleMems(const char *rolename, Oid roleid,
 
    forboth(specitem, memberSpecs, iditem, memberIds)
    {
-       RoleSpec   *memberRole = lfirst(specitem);
+       RoleSpec   *memberRole = lfirst_node(RoleSpec, specitem);
        Oid         memberid = lfirst_oid(iditem);
        HeapTuple   authmem_tuple;
        HeapTuple   tuple;