Revert to using --enable-auto-import in Cygwin builds.

Disabling auto-import requires that all libraries we use be careful about
declspecs for exported variables; and it seems they aren't.  This means
that Cygwin will not give us useful info about missing PGDLLIMPORT markers;
but it's probably sufficient that MSVC and Mingw builds do.
Fix unportable coding in tarCreateHeader().

uid_t and gid_t might be wider than int on some platforms.
Per buildfarm member brolga.
PGDLLIMPORT-ify MainLWLockArray, ProcDiePending, proc_exit_inprogress.

These are needed in HEAD to make assorted contrib modules build on Windows.
Now that all the MSVC and Mingw buildfarm members seem to be on the same
page about the need for them, we can have some confidence that future
problems of this ilk will be detected promptly; there seems nothing more
to be learned by delaying this fix further.

I chose to mark QueryCancelPending as well, since it's easy to imagine code
that wants to touch ProcDiePending also caring about QueryCancelPending.
Release notes for 9.3.3, 9.2.7, 9.1.12, 9.0.16, 8.4.20.
Shore up ADMIN OPTION restrictions.

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
Prevent privilege escalation in explicit calls to PL validators.

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
Document security implications of check_function_bodies.

Back-patch to 8.4 (all supported versions).
Avoid repeated name lookups during table and index DDL.

If the name lookups come to different conclusions due to concurrent
activity, we might perform some parts of the DDL on a different table
than other parts.  At least in the case of CREATE INDEX, this can be
used to cause the permissions checks to be performed against a
different table than the index creation, allowing for a privilege
escalation attack.

This changes the calling convention for DefineIndex, CreateTrigger,
transformIndexStmt, transformAlterTableStmt, CheckIndexCompatible
(in 9.2 and newer), and AlterTable (in 9.1 and older).  In addition,
CheckRelationOwnership is removed in 9.2 and newer and the calling
convention is changed in older branches.  A field has also been added
to the Constraint node (FkConstraint in 8.4).  Third-party code calling
these functions or using the Constraint node will require updating.

Report by Andres Freund.  Patch by Robert Haas and Andres Freund,
reviewed by Tom Lane.

Security: CVE-2014-0062
Fix handling of wide datetime input/output.

Many server functions use the MAXDATELEN constant to size a buffer for
parsing or displaying a datetime value.  It was much too small for the
longest possible interval output and slightly too small for certain
valid timestamp input, particularly input with a long timezone name.
The long input was rejected needlessly; the long output caused
interval_out() to overrun its buffer.  ECPG's pgtypes library has a copy
of the vulnerable functions, which bore the same vulnerabilities along
with some of its own.  In contrast to the server, certain long inputs
caused stack overflow rather than failing cleanly.  Back-patch to 8.4
(all supported versions).

Reported by Daniel Schüssler, reviewed by Tom Lane.

Security: CVE-2014-0063
Predict integer overflow to avoid buffer overruns.

Several functions, mostly type input functions, calculated an allocation
size such that the calculation wrapped to a small positive value when
arguments implied a sufficiently-large requirement.  Writes past the end
of the inadvertent small allocation followed shortly thereafter.
Coverity identified the path_in() vulnerability; code inspection led to
the rest.  In passing, add check_stack_depth() to prevent stack overflow
in related functions.

Back-patch to 8.4 (all supported versions).  The non-comment hstore
changes touch code that did not exist in 8.4, so that part stops at 9.0.

Noah Misch and Heikki Linnakangas, reviewed by Tom Lane.

Security: CVE-2014-0064
Prevent potential overruns of fixed-size buffers.

Coverity identified a number of places in which it couldn't prove that a
string being copied into a fixed-size buffer would fit.  We believe that
most, perhaps all of these are in fact safe, or are copying data that is
coming from a trusted source so that any overrun is not really a security
issue.  Nonetheless it seems prudent to forestall any risk by using
strlcpy() and similar functions.

Fixes by Peter Eisentraut and Jozef Mlich based on Coverity reports.

In addition, fix a potential null-pointer-dereference crash in
contrib/chkpass.  The crypt(3) function is defined to return NULL on
failure, but chkpass.c didn't check for that before using the result.
The main practical case in which this could be an issue is if libc is
configured to refuse to execute unapproved hashing algorithms (e.g.,
"FIPS mode").  This ideally should've been a separate commit, but
since it touches code adjacent to one of the buffer overrun changes,
I included it in this commit to avoid last-minute merge issues.
This issue was reported by Honza Horak.

Security: CVE-2014-0065 for buffer overruns, CVE-2014-0066 for crypt()
Document risks of "make check" in the regression testing instructions.

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
Improve documentation about multixact IDs.

Per gripe from Josh Berkus.
Fix capitalization in README.

Vik Fearing
Last-minute updates for release notes.

Add entries for security issues.

Security: CVE-2014-0060 through CVE-2014-0067
Fix comment; checkpointer, not bgwriter, performs checkpoints since 9.2.

Amit Langote
Disable RandomizedBaseAddress on MSVC builds

The ASLR in Windows 8/Windows 2012 can break PostgreSQL's shared memory. It
doesn't fail every time (which is explained by the Random part in ASLR), but
can fail with errors abut failing to reserve shared memory region.

MauMau, reviewed by Craig Ringer
Remove broken code that tried to handle OVERLAPS with a single argument.

The SQL standard says that OVERLAPS should have a two-element row
constructor on each side.  The original coding of OVERLAPS support in
our grammar attempted to extend that by allowing a single-element row
constructor, which it internally duplicated ... or tried to, anyway.
But that code has certainly not worked since our List infrastructure was
rewritten in 2004, and I'm none too sure it worked before that.  As it
stands, it ends up building a List that includes itself, leading to
assorted undesirable behaviors later in the parser.

Even if it worked as intended, it'd be a bit evil because of the
possibility of duplicate evaluation of a volatile function that the user
had written only once.  Given the lack of documentation, test cases, or
complaints, let's just get rid of the idea and only support the standard
syntax.

While we're at it, improve the error cursor positioning for the
wrong-number-of-arguments errors, and inline the makeOverlaps() function
since it's only called in one place anyway.

Per bug #9227 from Joshua Yanovski.  Initial patch by Joshua Yanovski,
extended a bit by me.
Add a pg_lsn data type, to represent an LSN.

Robert Haas and Michael Paquier
pg_lsn macro naming and type behavior revisions.

Change pg_lsn_mi so that it can return negative values when subtracting
LSNs, and clean up some perhaps ill-considered macro names.