Security Issues
---------------
Two security holes have been closed by this release:
CVE-2016-5423: certain nested CASE expressions can cause the server to crash.
CVE-2016-5424: database and role names with embedded special characters can allow code injection during administrative operations like pg_dumpall.
The fix for the second issue also adds an option, -reuse-previous, to psql's \connect command. pg_dumpall will also refuse to handle database and role names containing line breaks after the update. For more information on these issues and how they affect backwards-compatibility, see the Release Notes.
Bug Fixes and Improvements
--------------------------
This update also fixes a number of bugs reported in the last few months. Some of these issues affect only version 9.5, but many affect all supported versions:
Fix misbehaviors of IS NULL/IS NOT NULL with composite values
Fix three areas where INSERT ... ON CONFLICT failed to work properly with other SQL features.
Make INET and CIDR data types properly reject bad IPv6 values
Prevent crash in "point ## lseg" operator for NaN input
Avoid possible crash in pg_get_expr()
Fix several one-byte buffer over-reads in to_number()
Don't needlessly plan query if WITH NO DATA is specified
Avoid crash-unsafe state in expensive heap_update() paths
Fix hint bit update during WAL replay of row locking operations
Avoid unnecessary "could not serialize access" with FOR KEY SHARE
Avoid crash in postgres -C when the specified variable is a null string
Fix two issues with logical decoding and subtransactions
Ensure that backends see up-to-date statistics for shared catalogs
Prevent possible failure when vacuuming multixact IDs in an upgraded database
When a manual ANALYZE specifies columns, don't reset changes_since_analyze
Fix ANALYZE's overestimation of n_distinct for columns with nulls
Fix bug in b-tree mark/restore processing
Fix building of large (bigger than shared_buffers) hash indexes
Prevent infinite loop in GiST index build with NaN values
Fix possible crash during a nearest-neighbor indexscan
Fix "PANIC: failed to add BRIN tuple" error
Prevent possible crash during background worker shutdown
Many fixes for issues in parallel pg_dump and pg_restore
Make pg_basebackup accept -Z 0 as no compression
Make regression tests safe for Danish and Welsh locales
This release closes security hole CVE-2016-2193, where a query plan might get reused for more than one ROLE in the same session. This could cause the wrong set of Row Level Security (RLS) policies to be used for the query.
The update also fixes CVE-2016-3065, a server crash bug triggered by using pageinspect with BRIN index pages. Since an attacker might be able to expose a few bytes of server memory, this crash is being treated as a security issue.
This release primarily fixes issues not successfully fixed in prior releases. It should be applied as soon as possible all users of major versions 9.3 and 9.4. Other users should apply at the next available downtime.
Crash Recovery Fixes:
Earlier update releases attempted to fix an issue in PostgreSQL 9.3 and 9.4 with "multixact wraparound", but failed to account for issues doing multixact cleanup during crash recovery. This could cause servers to be unable to restart after a crash. As such, all users of 9.3 and 9.4 should apply this update as soon as possible.
Do it for all packages that
* mention perl, or
* have a directory name starting with p5-*, or
* depend on a package starting with p5-
like last time, for 5.18, where this didn't lead to complaints.
Let me know if you have any this time.
This update fixes CVE-2014-0060, in which PostgreSQL did not properly enforce the WITH ADMIN OPTION permission for ROLE management.
This update also fixes some issues which affect binary replication and row locking, and can cause recoverable data corruption in some cases.
In addition to the above, the following issues are fixed in this release:
Fix WAL logging of visibility map change
Make sure that GIN indexes log all insertions
Get pause_at_recovery_target to pause at correct time
Ensure walreceiver sends hot-standby feedback messages on time
Prevent timeout interrupts from taking control away from mainline code
Eliminate several race conditions
Fix some broken HINTs in error messages
Prevent server lockup on SSL connection loss
Fix two Unicode handling issues
Prevent crash on certain subselect syntax
Prevent crash on select from zero column table
Fix two bugs with LATERAL
Fix issue with UNION ALL, partitioning, and updates
Ensure that ANALYZE understands domains over ranges
Eliminate permissions check when using default tablespace
Fix memory leakage in JSON functions
Allow extensions with event triggers
Distinguish numbers correctly in JSON output
Fix permissions for pg_start_backup() and pg_stop_backup()
Accept SHIFT_JIS as locale name
Fix .* expansion for SQL function variables
Prevent infinite loop on some COPY connection failures
Several fixes for client issues on Windows
Enable building PostgreSQL with Visual Studio 2013
Update time zone files for recent changes
a) refer 'perl' in their Makefile, or
b) have a directory name of p5-*, or
c) have any dependency on any p5-* package
Like last time, where this caused no complaints.
The security issue fixed in this release, CVE-2013-0255, allows a previously authenticated user to crash the server by calling an internal function with invalid arguments. This issue was discovered by independent security researcher Sumit Soni this week and reported via Secunia SVCRP, and we are grateful for their efforts in making PostgreSQL more secure.
Today's update also fixes a performance regression which caused a decrease in throughput when using dynamic queries in stored procedures in version 9.2. Applications which use PL/pgSQL's EXECUTE are strongly affected by this regression and should be updated. Additionally, we have fixed intermittent crashes caused by CREATE/DROP INDEX CONCURRENTLY, and multiple minor issues with replication.
This release is expected to be the final update for version 8.3, which is now End-of-Life (EOL). Users of version 8.3 should plan to upgrade to a later version of PostgreSQL immediately. For more information, see our Versioning Policy.
This update release also contains fixes for many minor issues discovered and patched by the PostgreSQL community in the last two months, including:
* Prevent unnecessary table scans during vacuuming
* Prevent spurious cached plan error in PL/pgSQL
* Allow sub-SELECTs to be subscripted
* Prevent DROP OWNED from dropping databases or tablespaces
* Make ECPG use translated messages
* Allow PL/Python to use multi-table trigger functions (again) in 9.1 and 9.2
* Fix several activity log management issues on Windows
* Prevent autovacuum file truncation from being cancelled by deadlock_timeout
* Make extensions build with the .exe suffix automatically on Windows
* Fix concurrency issues with CREATE/DROP DATABASE
* Reject out-of-range values in to_date() conversion function
* Revert cost estimation for large indexes back to pre-9.2 behavior
* Make pg_basebackup tolerate timeline switches
* Cleanup leftover temp table entries during crash recovery
* Prevent infinite loop when COPY inserts a large tuple into a table with a large fillfactor
* Prevent integer overflow in dynahash creation
* Make pg_upgrade work with INVALID indexes
* Fix bugs in TYPE privileges
* Allow Contrib installchecks to run in their own databases
* Many documentation updates
* Add new timezone "FET".
PostgreSQL 9.2 will ship with native JSON support, covering indexes, replication and performance improvements, and many more features. We are eagerly awaiting this release and will make it available in Early Access as soon as it’s released by the PostgreSQL community," said Ines Sombra, Lead Data Engineer, Engine Yard.
