Head patch was 42ec6c2d.

Reported-by: Alexander Law

Discussion: 5785FBE7.7060508@gmail.com

Backpatch-through: 9.1

Per the fgets() specification, it cannot return without reading some data
unless it reports EOF or error.  So the code here assumed that the data
buffer would necessarily be nonempty when we go to check for a newline
having been read.  However, Agostino Sarubbo noticed that this could fail
to be true if the first byte of the data is a NUL (\0).  The fgets() API
doesn't really work for embedded NULs, which is something I don't feel
any great need for us to worry about since we generally don't allow NULs
in SQL strings anyway.  But we should not access off the end of our own
buffer if the case occurs.  Normally this would just be a harmless read,
but if you were unlucky the byte before the buffer would contain '\n'
and we'd overwrite it with '\0', and if you were really unlucky that
might be valuable data and psql would crash.

Agostino reported this to pgsql-security, but after discussion we concluded
that it isn't worth treating as a security bug; if you can control the
input to psql you can do far more interesting things than just maybe-crash
it.  Nonetheless, it is a bug, so back-patch to all supported versions.

Commits 4452000f et al established semantics for NullTest.argisrow that
are a bit different from its initial conception: rather than being merely
a cache of whether we've determined the input to have composite type,
the flag now has the further meaning that we should apply field-by-field
testing as per the standard's definition of IS [NOT] NULL.  If argisrow
is false and yet the input has composite type, the construct instead has
the semantics of IS [NOT] DISTINCT FROM NULL.  Update the comments in
primnodes.h to clarify this, and fix ruleutils.c and deparse.c to print
such cases correctly.  In the case of ruleutils.c, this merely results in
cosmetic changes in EXPLAIN output, since the case can't currently arise
in stored rules.  However, it represents a live bug for deparse.c, which
would formerly have sent a remote query that had semantics different
from the local behavior.  (From the user's standpoint, this means that
testing a remote nested-composite column for null-ness could have had
unexpected recursive behavior much like that fixed in 4452000f.)

In a related but somewhat independent fix, make plancat.c set argisrow
to false in all NullTest expressions constructed to represent "attnotnull"
constructs.  Since attnotnull is actually enforced as a simple null-value
check, this is a more accurate representation of the semantics; we were
previously overpromising what it meant for composite columns, which might
possibly lead to incorrect planner optimizations.  (It seems that what the
SQL spec expects a NOT NULL constraint to mean is an IS NOT NULL test, so
arguably we are violating the spec and should fix attnotnull to do the
other thing.  If we ever do, this part should get reverted.)

Back-patch, same as the previous commit.

Discussion: <10682.1469566308@sss.pgh.pa.us>

The docs failed to explain that LIKE INCLUDING INDEXES would not preserve
the names of indexes and associated constraints.  Also, it wasn't mentioned
that EXCLUDE constraints would be copied by this option.  The latter
oversight seems enough of a documentation bug to justify back-patching.

In passing, do some minor copy-editing in the same area, and add an entry
for LIKE under "Compatibility", since it's not exactly a faithful
implementation of the standard's feature.

Discussion: <20160728151154.AABE64016B@smtp.hushmail.com>

start_postmaster() registered stop_postmaster_atexit as an atexit(3)
callback each time through, although the obvious intention was to do
so only once per program run.  The extra registrations were harmless,
so long as we didn't exceed ATEXIT_MAX, but still it's a bug.

Artur Zakirov, with bikeshedding by Kyotaro Horiguchi and me

Discussion: <d279e817-02b5-caa6-215f-cfb05dce109a@postgrespro.ru>

The description of udt_privileges view contained an incorrect copy-pasted word.

Back-patch to 9.2 where udt_privileges view was added.

Author: Alexander Law

The SQL standard appears to specify that IS [NOT] NULL's tests of field
nullness are non-recursive, ie, we shouldn't consider that a composite
field with value ROW(NULL,NULL) is null for this purpose.
ExecEvalNullTest got this right, but eval_const_expressions did not,
leading to weird inconsistencies depending on whether the expression
was such that the planner could apply constant folding.

Also, adjust the docs to mention that IS [NOT] DISTINCT FROM NULL can be
used as a substitute test if a simple null check is wanted for a rowtype
argument.  That motivated reordering things so that IS [NOT] DISTINCT FROM
is described before IS [NOT] NULL.  In HEAD, I went a bit further and added
a table showing all the comparison-related predicates.

Per bug #14235.  Back-patch to all supported branches, since it's certainly
undesirable that constant-folding should change the semantics.

Report and patch by Andrew Gierth; assorted wordsmithing and revised
regression test cases by me.

Report: <20160708024746.1410.57282@wrigleys.postgresql.org>

Use our typical approach, from src/backend/parser.  Back-patch to 9.1
(all supported versions).

In btree_gin and citext, avoid some not-particularly-interesting
dependencies on the sorting of 'aa'.  In tsearch2, use COLLATE "C" to
remove an uninteresting dependency on locale sort order (and thereby
allow removal of a variant expected-file).

Also, in citext, avoid assuming that lower('I') = 'i'.  This isn't relevant
to Danish but it does fail in Turkish.

Another peculiarity of Danish locale is that it has an unusual idea
of how to sort upper vs. lower case.  One of the pltcl test cases has
an issue with that.  Now that COLLATE works in all supported branches,
we can just change the test to be locale-independent, and get rid of
the variant expected file that used to support non-C locales.

Ooops, I missed back-patching commit f5f15ea6 along with the other stuff.

Back-patch commit 1c1a7cbd, along with subsequent portability
fixes, into all active branches.  Also, back-patch commits 69602772 and
59685704 (addition of zic -P option) into 9.1 and 9.2, just to reduce
differences between the branches.  src/timezone/ is now largely identical
in all active branches, except that in 9.1, pgtz.c retains the
initial-timezone-selection code that was moved over to initdb in 9.2.

Ordinarily we wouldn't risk this much code churn in back branches, but it
seems necessary in this case, because among the changes are two feature
additions in the "zic" zone data file compiler (a larger limit on the
number of allowed DST transitions, and addition of a "%z" escape in zone
abbreviations).  IANA have not yet started to use those features in their
tzdata files, but presumably they will before too long.  If we don't update
then we'll be unable to adopt new timezone data.  Also, installations built
with --with-system-tzdata (which includes most distro-supplied builds, I
believe) might fail even if we don't update our copies of the data files.
There are assorted bug fixes too, mostly affecting obscure timezones or
post-2037 dates.

Discussion: <13601.1468868947@sss.pgh.pa.us>

The old code used SEQ_MINVALUE to get the smallest int64 value.  This
was done as a convenience to avoid having to deal with INT64_IS_BUSTED,
but that is obsolete now.  Also, it is incorrect because the smallest
int64 value is actually SEQ_MINVALUE-1.  Fix by writing out the constant
the long way, as it is done elsewhere in the code.

The Assert() here seems unreasonably optimistic.  Andreas Seltenreich
found that it could fail with NaNs in the input geometries, and it
seems likely to me that it might fail in corner cases due to roundoff
error, even for ordinary input values.  As a band-aid, make the function
return SQL NULL instead of crashing.

Report: <87d1md1xji.fsf@credativ.de>

When heap_update needs to look for a page for the new tuple version,
because the current one doesn't have sufficient free space, or when
columns have to be processed by the tuple toaster, it has to release the
lock on the old page during that. Otherwise there'd be lock ordering and
lock nesting issues.

To avoid concurrent sessions from trying to update / delete / lock the
tuple while the page's content lock is released, the tuple's xmax is set
to the current session's xid.

That unfortunately was done without any WAL logging, thereby violating
the rule that no XIDs may appear on disk, without an according WAL
record.  If the database were to crash / fail over when the page level
lock is released, and some activity lead to the page being written out
to disk, the xid could end up being reused; potentially leading to the
row becoming invisible.

There might be additional risks by not having t_ctid point at the tuple
itself, without having set the appropriate lock infomask fields.

To fix, compute the appropriate xmax/infomask combination for locking
the tuple, and perform WAL logging using the existing XLOG_HEAP_LOCK
record. That allows the fix to be backpatched.

This issue has existed for a long time. There appears to have been
partial attempts at preventing dangers, but these never have fully been
implemented, and were removed a long time ago, in
11919160 (cf. HEAP_XMAX_UNLOGGED).

In master / 9.6, there's an additional issue, namely that the
visibilitymap's freeze bit isn't reset at that point yet. Since that's a
new issue, introduced only in a892234f, that'll be fixed in a
separate commit.

Author: Masahiko Sawada and Andres Freund
Reported-By: Different aspects by Thomas Munro, Noah Misch, and others
Discussion: CAEepm=3fWAbWryVW9swHyLTY4sXVf0xbLvXqOwUoDiNCx9mBjQ@mail.gmail.com
Backpatch: 9.1/all supported versions

From: Alexander Law <exclusion@gmail.com>

GiST index build could go into an infinite loop when presented with boxes
(or points, circles or polygons) containing NaN component values.  This
happened essentially because the code assumed that x == x is true for any
"double" value x; but it's not true for NaNs.  The looping behavior was not
the only problem though: we also attempted to sort the items using simple
double comparisons.  Since NaNs violate the trichotomy law, qsort could
(in principle at least) get arbitrarily confused and mess up the sorting of
ordinary values as well as NaNs.  And we based splitting choices on box size
calculations that could produce NaNs, again resulting in undesirable
behavior.

To fix, replace all comparisons of doubles in this logic with
float8_cmp_internal, which is NaN-aware and is careful to sort NaNs
consistently, higher than any non-NaN.  Also rearrange the box size
calculation to not produce NaNs; instead it should produce an infinity
for a box with NaN on one side and not-NaN on the other.

I don't by any means claim that this solves all problems with NaNs in
geometric values, but it should at least make GiST index insertion work
reliably with such data.  It's likely that the index search side of things
still needs some work, and probably regular geometric operations too.
But with this patch we're laying down a convention for how such cases
ought to behave.

Per bug #14238 from Guang-Dih Lei.  Back-patch to 9.2; the code used before
commit 7f3bd868 is quite different and doesn't lock up on my simple
test case, nor on the submitter's dataset.

Report: <20160708151747.1426.60150@wrigleys.postgresql.org>
Discussion: <28685.1468246504@sss.pgh.pa.us>

Back-patch relevant parts of commit 30b2731b into 9.1-9.3.

Michael Paquier, Kyotaro Horiguchi

Discussion: <20160704.160213.111134711.horiguchi.kyotaro@lab.ntt.co.jp>

Document that index storage is dependent on the operating system's
collation library ordering, and any change in that ordering can create
invalid indexes.

Discussion: 20160617154311.GB19359@momjian.us

Backpatch-through: 9.1

Commit 0b0baf26 et al made this case print "(null)" on the grounds that
that's what happened on platforms that didn't crash.  But neither behavior
was actually intentional.  What we should print is just an empty string,
for compatibility with the behavior of SHOW and other ways of examining
string GUCs.  Those code paths don't distinguish NULL from empty strings,
so we should not here either.  Per gripe from Alain Radix.

Like the previous patch, back-patch to 9.2 where -C option was introduced.

Discussion: <CA+YdpwxPUADrmxSD7+Td=uOshMB1KkDN7G7cf+FGmNjjxMhjbw@mail.gmail.com>

If there's anyplace in our SGML docs that explains this behavior, I can't
find it right at the moment.  Add an explanation in "Dependency Tracking"
which seems like the authoritative place for such a discussion.  Per
gripe from Michelle Schwan.

While at it, update this section's example of a dependency-related
error message: they last looked like that in 8.3.  And remove the
explanation of dependency updates from pre-7.3 installations, which
is probably no longer worth anybody's brain cells to read.

The bogus error message example seems like an actual documentation bug,
so back-patch to all supported branches.

Discussion: <20160620160047.5792.49827@wrigleys.postgresql.org>

Dilian Palauzov pointed out in bug #14201 that the docs failed to mention
the possibility of %R producing '(' due to an unmatched parenthesis.

He proposed just adding that in the same style as the other options were
listed; but it seemed to me that the sentence was already nearly
unintelligible, so I rewrote it a bit more extensively.

Report: <20160619121113.5789.68274@wrigleys.postgresql.org>

The inet/cidr types sometimes failed to reject IPv6 inputs with too many
colon-separated fields, instead translating them to '::/0'.  This is the
result of a thinko in the original ISC code that seems to be as yet
unreported elsewhere.  Per bug #14198 from Stefan Kaltenbrunner.

Report: <20160616182222.5798.959@wrigleys.postgresql.org>

Emit "(null)" instead, which was the behavior all along on platforms
that don't crash, eg OS X.  Per report from Jehan-Guillaume de Rorthais.
Back-patch to 9.2 where -C option was introduced.

Michael Paquier

Report: <20160615204036.2d35d86a@firost>

pg_type_aclmask reported the wrong type's OID when complaining that
it could not find a type's typelem.  It also failed to provide a
suitable errcode when the initially given OID doesn't exist (which
is a user-facing error, since that OID can be user-specified).
pg_foreign_data_wrapper_aclmask and pg_foreign_server_aclmask likewise
lacked errcode specifications.  Trivial cosmetic adjustments too.

The wrong-type-OID problem was reported by Petru-Florin Mihancea in
bug #14186; the other issues noted by me while reading the code.
These errors all seem to be aboriginal in the respective routines, so
back-patch as necessary.

Report: <20160613163159.5798.52928@wrigleys.postgresql.org>

Document these as "nearest integer >= argument" and "nearest integer <=
argument", which will hopefully be less confusing than the old formulation.
New wording is from Matlab via Dean Rasheed.

I changed the pg_description entries as well as the SGML docs.  In the
back branches, this will only affect installations initdb'd in the future,
but it should be harmless otherwise.

Discussion: <CAEZATCW3yzJo-NMSiQs5jXNFbTsCEftZS-Og8=FvFdiU+kYuSA@mail.gmail.com>

In VPATH builds, the build directory was not being searched for files in
GETTEXT_FILES, leading to failure to construct the .pot files.  This has
bit me all along, but never hard enough to get it fixed; I suppose not a
lot of people uses VPATH and NLS-enabled builds, and those that do,
don't do "make update-po" often.

This is a longstanding problem, so backpatch all the way back.

If we ANALYZE only selected columns of a table, we should not postpone
auto-analyze because of that; other columns may well still need stats
updates.  As committed, the counter is left alone if a column list is
given, whether or not it includes all analyzable columns of the table.
Per complaint from Tomasz Ostrowski.

It's been like this a long time, so back-patch to all supported branches.

Report: <ef99c1bd-ff60-5f32-2733-c7b504eb960c@ato.waw.pl>

VACUUM FREEZE generated false cancelations of standby queries on an
otherwise idle master. Caused by an off-by-one error on cutoff_xid
which goes back to original commit.

Analysis and report by Marco Nenciarini

Bug fix by Simon Riggs

This is a correct backpatch of commit 66fbcb0d to branches 9.1 through
9.4.  That commit was backpatched to 9.0 originally, but it was
immediately reverted in 9.0-9.4 because it didn't compile.

Because vac_update_datfrozenxid() updates datfrozenxid and datminmxid
in-place, it's unsafe to assume that successive reads of those values will
give consistent results.  Fetch each one just once to ensure sane behavior
in the minimum calculation.  Noted while reviewing Alexander Korotkov's
patch in the same area.

Discussion: <8564.1464116473@sss.pgh.pa.us>

vac_truncate_clog() uses its own transaction ID as the comparison point in
a sanity check that no database's datfrozenxid has already wrapped around
"into the future".  That was probably fine when written, but in a lazy
vacuum we won't have assigned an XID, so calling GetCurrentTransactionId()
causes an XID to be assigned when otherwise one would not be.  Most of the
time that's not a big problem ... but if we are hard up against the
wraparound limit, consuming XIDs during antiwraparound vacuums is a very
bad thing.

Instead, use ReadNewTransactionId(), which not only avoids this problem
but is in itself a better comparison point to test whether wraparound
has already occurred.

Report and patch by Alexander Korotkov.  Back-patch to all versions.

Report: <CAPpHfdspOkmiQsxh-UZw2chM6dRMwXAJGEmmbmqYR=yvM7-s6A@mail.gmail.com>

do_text_output_multiline() would fail (typically with a null pointer
dereference crash) if its input string did not end with a newline.  Such
cases do not arise in our current sources; but it certainly could happen
in future, or in extension code's usage of the function, so we should fix
it.  To fix, replace "eol += len" with "eol = text + len".

While at it, make two cosmetic improvements: mark the input string const,
and rename the argument from "text" to "txt" to dodge pgindent strangeness
(since "text" is a typedef name).

Even though this problem is only latent at present, it seems like a good
idea to back-patch the fix, since it's a very simple/safe patch and it's
not out of the realm of possibility that we might in future back-patch
something that expects sane behavior from do_text_output_multiline().

Per report from Hao Lee.

Report: <CAGoxFiFPAGyPAJLcFxTB5cGhTW2yOVBDYeqDugYwV4dEd1L_Ag@mail.gmail.com>

Mention it in the Notes section too, per suggestion from David Johnston.

Discussion: <20160520165824.22598.31426@wrigleys.postgresql.org>

Per bug #14152 from Alejandro Martínez.  Back-patch to all supported
branches.

Discussion: <20160520165824.22598.31426@wrigleys.postgresql.org>

From: Alexander Law <exclusion@gmail.com>

Buildfarm member skink failed with symptoms suggesting that an
auto-analyze had happened and changed the plan displayed for a
test query.  Although this is evidently of low probability,
regression tests that sometimes fail are no fun, so add commands
to force a bitmap scan to be chosen.

The table-skipping logic in autovacuum would fail to consider that
multiple workers could be processing the same shared catalog in
different databases.  This normally wouldn't be a problem: firstly
because autovacuum workers not for wraparound would simply ignore tables
in which they cannot acquire lock, and secondly because most of the time
these tables are small enough that even if multiple for-wraparound
workers are stuck in the same catalog, they would be over pretty
quickly.  But in cases where the catalogs are severely bloated it could
become a problem.

Backpatch all the way back, because the problem has been there since the
beginning.

Reported by Ondřej Světlík

Discussion: https://www.postgresql.org/message-id/572B63B1.3030603%40flexibee.eu
	https://www.postgresql.org/message-id/572A1072.5080308%40flexibee.eu

Source-Git-URL: git://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: 32e77ddc0a1641ccc73056a7c2113264ba2942ff