Andres Freund

With the GIN "fast scan" feature, GIN can skip items without fetching all
the keys for them, if it can prove that they don't match regardless of
those keys. So far, it has done the proving by calling the boolean
consistent function with all combinations of TRUE/FALSE for the unfetched
keys, but since that's O(n^2), it becomes unfeasible with more than a few
keys. We can avoid calling consistent with all the combinations, if we can
tell the operator class implementation directly which keys are unknown.

This commit includes a triConsistent function for the built-in array and
tsvector opclasses.

Alexander Korotkov, with some changes by me.

In order for this to work, walsenders need the optional ability to
connect to a database, so the "replication" keyword now allows true
or false, for backward-compatibility, and the new value "database"
(which causes the "dbname" parameter to be respected).

walsender needs to loop not only when idle but also when sending
decoded data to the user and when waiting for more xlog data to decode.
This means that there are now three separate loops inside walsender.c;
although some refactoring has been done here, this is still a bit ugly.

Andres Freund, with contributions from Álvaro Herrera, and further
review by me.

Return '4' and report a meaningful error message when a non-existent or
invalid data directory is passed.  Previously, pg_ctl would just report
the server was not running.

Patch by me and Amit Kapila
Report from Peter Eisentraut

Per report by Marc Mamin

Use superior libpq keepalive description for the server-level
parameters.

Per report by Tatsuo Ishii and Marko Tiikkaja

Initial patch by Colin 't Hart

Item is "Prevent errors in WAL replay due to references to uninitialized
empty pages".

Report and text by Andres Freund

Backpatch through 9.2.

Michael Paquier

Initial patch from Steve Crawford

This forces an input field containing the quoted null string to be
returned as a NULL. Without this option, only unquoted null strings
behave this way. This helps where some CSV producers insist on quoting
every field, whether or not it is needed. The option takes a list of
fields, and only applies to those columns. There is an equivalent
column-level option added to file_fdw.

Ian Barwick, with some tweaking by Andrew Dunstan, reviewed by Payal
Singh.

Author: Kyotaro HORIGUCHI
Reviewed-by: Jaime Casanova

Author: Pavel Stěhule, editorialized somewhat by Álvaro Herrera
Reviewed-by: Tomáš Vondra, Marko Tiikkaja
With input from Fabrízio de Royes Mello, Jim Nasby

This feature, building on previous commits, allows the write-ahead log
stream to be decoded into a series of logical changes; that is,
inserts, updates, and deletes and the transactions which contain them.
It is capable of handling decoding even across changes to the schema
of the effected tables.  The output format is controlled by a
so-called "output plugin"; an example is included.  To make use of
this in a real replication system, the output plugin will need to be
modified to produce output in the format appropriate to that system,
and to perform filtering.

Currently, information can be extracted from the logical decoding
system only via SQL; future commits will add the ability to stream
changes via walsender.

Andres Freund, with review and other contributions from many other
people, including Álvaro Herrera, Abhijit Menon-Sen, Peter Gheogegan,
Kevin Grittner, Robert Haas, Heikki Linnakangas, Fujii Masao, Abhijit
Menon-Sen, Michael Paquier, Simon Riggs, Craig Ringer, and Steve
Singer.

Christian Kruse

This option makes pg_dump, pg_dumpall and pg_restore inject an IF EXISTS
clause to each DROP command they emit.  (In pg_dumpall, the clause is
not added to individual objects drops, but rather to the CREATE DATABASE
commands, as well as CREATE ROLE and CREATE TABLESPACE.)

This allows for a better user dump experience when using --clean in case
some objects do not already exist.  Per bug #7873 by Dave Rolsky.

Author: Pavel Stěhule
Reviewed-by: Jeevan Chalke, Álvaro Herrera, Josh Kupershmidt

Andres Freund, per a report from Vik Faering

A new MAX_RATE option allows imposing a limit to the network transfer
rate from the server side.  This is useful to limit the stress that
taking a base backup has on the server.

pg_basebackup is now able to specify a value to the server, too.

Author: Antonin Houska

Patch reviewed by Stefan Radomski, Andres Freund, Zoltán Böszörményi,
Fujii Masao, and Álvaro Herrera.

Per report from James Harper.

Christian Kruse, reviewed by Andres Freund and myself, with further
minor adjustments by me.

- Write HIGH:MEDIUM instead of DEFAULT:!LOW:!EXP for clarity.
- Order 3DES last to work around inappropriate OpenSSL default.
- Remove !MD5 and @STRENGTH, because they are irrelevant.
- Add clarifying documentation.

Effectively, the new default is almost the same as the old one, but it
is arguably easier to understand and modify.

Author: Marko Kreen <markokr@gmail.com>

New defaults are 4MB and 64MB.

Space trimming rather than space-padding causes unusual behavior, which
might not be standards-compliant.

Also remove recently-added now-redundant C comment.

Michael Paquier, per a suggestion from Andres Freund

DocBook XML is superficially compatible with DocBook SGML but has a
slightly stricter DTD that we have been violating in a few cases.
Although XSLT doesn't care whether the document is valid, the style
sheets don't necessarily process invalid documents correctly, so we need
to work toward fixing this.

This first commit moves the indexterms in refentry elements to an
allowed position.  It has no impact on the output.

Tablespaces can be relocated in plain backup mode by specifying one or
more -T olddir=newdir options.

Author: Steeve Lennmark <steevel@handeldsbanken.se>
Reviewed-by: Peter Eisentraut <peter_e@gmx.net>

The customization overrode the fast-forward code with its custom Up
link.  So this is no longer really the fast-forward feature, so we might
as well turn that off and override the non-ff template instead, thus
removing one mental indirection.

Fix the wrong column span declaration.

Clarify and update the documentation.

Per an observation from Amit Kapila.

The functions in slotfuncs.c don't exist in any released version,
but the changes to xlogfuncs.c represent backward-incompatibilities.
Per discussion, we're hoping that the queries using these functions
are few enough and simple enough that this won't cause too much
breakage for users.

Michael Paquier, reviewed by Andres Freund and further modified
by me.

Robert Haas and Michael Paquier

Add entries for security issues.

Security: CVE-2014-0060 through CVE-2014-0067

Per gripe from Josh Berkus.

Since the temporary server started by "make check" uses "trust"
authentication, another user on the same machine could connect to it
as database superuser, and then potentially exploit the privileges of
the operating-system user who started the tests.  We should change
the testing procedures to prevent this risk; but discussion is required
about the best way to do that, as well as more testing than is practical
for an undisclosed security problem.  Besides, the same issue probably
affects some user-written test harnesses.  So for the moment, we'll just
warn people against using "make check" when there are untrusted users on
the same machine.

In passing, remove some ancient advice that suggested making the
regression testing subtree world-writable if you'd built as root.
That looks dangerously insecure in modern contexts, and anyway we
should not be encouraging people to build Postgres as root.

Security: CVE-2014-0067

Back-patch to 8.4 (all supported versions).

The primary role of PL validators is to be called implicitly during
CREATE FUNCTION, but they are also normal functions that a user can call
explicitly.  Add a permissions check to each validator to ensure that a
user cannot use explicit validator calls to achieve things he could not
otherwise achieve.  Back-patch to 8.4 (all supported versions).
Non-core procedural language extensions ought to make the same two-line
change to their own validators.

Andres Freund, reviewed by Tom Lane and Noah Misch.

Security: CVE-2014-0061

Granting a role without ADMIN OPTION is supposed to prevent the grantee
from adding or removing members from the granted role.  Issuing SET ROLE
before the GRANT bypassed that, because the role itself had an implicit
right to add or remove members.  Plug that hole by recognizing that
implicit right only when the session user matches the current role.
Additionally, do not recognize it during a security-restricted operation
or during execution of a SECURITY DEFINER function.  The restriction on
SECURITY DEFINER is not security-critical.  However, it seems best for a
user testing his own SECURITY DEFINER function to see the same behavior
others will see.  Back-patch to 8.4 (all supported versions).

The SQL standards do not conflate roles and users as PostgreSQL does;
only SQL roles have members, and only SQL users initiate sessions.  An
application using PostgreSQL users and roles as SQL users and roles will
never attempt to grant membership in the role that is the session user,
so the implicit right to add or remove members will never arise.

The security impact was mostly that a role member could revoke access
from others, contrary to the wishes of his own grantor.  Unapproved role
member additions are less notable, because the member can still largely
achieve that by creating a view or a SECURITY DEFINER function.

Reviewed by Andres Freund and Tom Lane.  Reported, independently, by
Jonas Sundman and Noah Misch.

Security: CVE-2014-0060