db69e58a06
In the plancache, we check if the environment we planned the query under has changed in a way which requires us to re-plan, such as when the user for whom the plan was prepared changes and RLS is being used (and, therefore, there may be different policies to apply). Unfortunately, while those values were set and checked, they were not being reset when the query was re-planned and therefore, in cases where we change role, re-plan, and then change role again, we weren't re-planning again. This leads to potentially incorrect policies being applied in cases where role-specific policies are used and a given query is planned under one role and then executed under other roles, which could happen under security definer functions or when a common user and query is planned initially and then re-used across multiple SET ROLEs. Further, extensions which made use of CopyCachedPlan() may suffer from similar issues as the RLS-related fields were not properly copied as part of the plan and therefore RevalidateCachedQuery() would copy in the current settings without invalidating the query. Fix by using the same approach used for 'search_path', where we set the correct values in CompleteCachedPlan(), check them early on in RevalidateCachedQuery() and then properly reset them if re-planning. Also, copy through the values during CopyCachedPlan(). Pointed out by Ashutosh Bapat. Reviewed by Michael Paquier. Back-patch to 9.5 where RLS was introduced. Security: CVE-2016-2193
PostgreSQL Database Management System ===================================== This directory contains the source code distribution of the PostgreSQL database management system. PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings. PostgreSQL has many language interfaces, many of which are listed here: http://www.postgresql.org/download See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at http://www.postgresql.org/download/. For more information look at our web site located at http://www.postgresql.org/.