Restore 4-byte designation for docs. Fix 9.3 doc query to properly pad
to four digits.
Backpatch to all active branches
Per suggestions from Ian Lawrence Barwick
WAL segment means a 16 MB physical WAL file; this comment meant a logical
4 GB log file.
Amit Langote. Apply to backbranches only, as the comment is gone in master.
A view defined as "select <something> where false" had the curious property
that the system wouldn't check whether users had the privileges necessary
to select from it. More generally, permissions checks could be skipped
for tables referenced in sub-selects or views that were proven empty by
constraint exclusion (although some quick testing suggests this seldom
happens in cases of practical interest). This happened because the planner
failed to include rangetable entries for such tables in the finished plan.
This was noticed in connection with erroneous handling of materialized
views, but actually the issue is quite unrelated to matviews. Therefore,
revert commit 200ba1667b3a8d7a9d559d2f05f83d209c9d8267 in favor of a more
direct test for the real problem.
Back-patch to 9.2 where the bug was introduced (by commit
7741dd6590073719688891898e85f0cb73453159).
This is a follow-up to the earlier fix, which changed the recycling logic
to recycle WAL segments under the current recovery target timeline. That
turns out to be a bad idea, because installing a recycled segment with
a TLI higher than what we're recovering at the moment means that the recovery
logic will find the recycled WAL segment and try to replay it. It will fail,
but but the mere presence of such a WAL segment will mask any other, real,
file with the same log/seg, but smaller TLI.
Per report from Mitsumasa Kondo. Apply to 9.1 and 9.2, like the previous
fix. Master was already doing this differently; this patch makes 9.1 and
9.2 to do the same thing as master.
This patch gets rid of the concept of, and infrastructure for,
non-canonical PathKeys; we now only ever create canonical pathkey lists.
The need for non-canonical pathkeys came from the desire to have
grouping_planner initialize query_pathkeys and related pathkey lists before
calling query_planner. However, since query_planner didn't actually *do*
anything with those lists before they'd been made canonical, we can get rid
of the whole mess by just not creating the lists at all until the point
where we formerly canonicalized them.
There are several ways in which we could implement that without making
query_planner itself deal with grouping/sorting features (which are
supposed to be the province of grouping_planner). I chose to add a
callback function to query_planner's API; other alternatives would have
required adding more fields to PlannerInfo, which while not bad in itself
would create an ABI break for planner-related plugins in the 9.2 release
series. This still breaks ABI for anything that calls query_planner
directly, but it seems somewhat unlikely that there are any such plugins.
I had originally conceived of this change as merely a step on the way to
fixing bug #8049 from Teun Hoogendoorn; but it turns out that this fixes
that bug all by itself, as per the added regression test. The reason is
that now get_eclass_for_sort_expr is adding the ORDER BY expression at the
end of EquivalenceClass creation not the start, and so anything that is in
a multi-member EquivalenceClass has already been created with correct
em_nullable_relids. I am suspicious that there are related scenarios in
which we still need to teach get_eclass_for_sort_expr to compute correct
nullable_relids, but am not eager to risk destabilizing either 9.2 or 9.3
to fix bugs that are only hypothetical. So for the moment, do this and
stop here.
Back-patch to 9.2 but not to earlier branches, since they don't exhibit
this bug for lack of join-clause-movement logic that depends on
em_nullable_relids being correct. (We might have to revisit that choice
if any related bugs turn up.) In 9.2, don't change the signature of
make_pathkeys_for_sortclauses nor remove canonicalize_pathkeys, so as
not to risk more plugin breakage than we have to.
Patch b19e4250b45e91c9cbdd18d35ea6391ab5961c8d attempted to
preserve existing behavior regarding statistics generation in the
case that a truncation attempt was canceled due to lock conflicts.
It failed to do this accurately in two regards: (1) autovacuum had
previously generated statistics if the truncate attempt failed to
initially get the lock rather than having started the attempt, and
(2) the VACUUM ANALYZE command had always generated statistics.
Both of these changes were unintended, and are reverted by this
patch. On review, there seems to be consensus that the previous
failure to generate statistics when the truncate was terminated
was more an unfortunate consequence of how that effort was
previously terminated than a feature we want to keep; so this
patch generates statistics even when an autovacuum truncation
attempt terminates early. Another unintended change which is kept
on the basis that it is an improvement is that when a VACUUM
command is truncating, it will the new heuristic for avoiding
blocking other processes, rather than keeping an
AccessExclusiveLock on the table for however long the truncation
takes.
Per multiple reports, with some renaming per patch by Jeff Janes.
Backpatch to 9.0, where problem was created.
There was a high probability of two or more concurrent C.I.C. commands
deadlocking just before completion, because each would wait for the others
to release their reference snapshots. Fix by releasing the snapshot
before waiting for other snapshots to go away.
Per report from Paul Hinze. Back-patch to all active branches.
When creating or manipulating a cached plan for a transaction control
command (particularly ROLLBACK), we must not perform any catalog accesses,
since we might be in an aborted transaction. However, plancache.c busily
saved or examined the search_path for every cached plan. If we were
unlucky enough to do this at a moment where the path's expansion into
schema OIDs wasn't already cached, we'd do some catalog accesses; and with
some more bad luck such as an ill-timed signal arrival, that could lead to
crashes or Assert failures, as exhibited in bug #8095 from Nachiket Vaidya.
Fortunately, there's no real need to consider the search path for such
commands, so we can just skip the relevant steps when the subject statement
is a TransactionStmt. This is somewhat related to bug #5269, though the
failure happens during initial cached-plan creation rather than
revalidation.
This bug has been there since the plan cache was invented, so back-patch
to all supported branches.
The old formula didn't take into account that each WAL sender process needs
a spinlock. We had also already exceeded the fixed number of spinlocks
reserved for misc purposes (10). Bump that to 30.
Backpatch to 9.0, where WAL senders were introduced. If I counted correctly,
9.0 had exactly 10 predefined spinlocks, and 9.1 exceeded that, but bump the
limit in 9.0 too because 10 is uncomfortably close to the edge.
The point of turning off track_activities is to avoid this reporting
overhead, but a thinko in commit 4f42b546fd87a80be30c53a0f2c897acb826ad52
caused pgstat_report_activity() to perform half of its updates anyway.
Fix that, and also make sure that we clear all the now-disabled fields
when transitioning to the non-reporting state.
Notice and complain about PQcancel() failures. Also, don't dump core if
an error PGresult doesn't contain severity and message subfields, as it
might not if it was generated by libpq itself. (We have a longstanding
TODO item to improve that, but in the meantime isolationtester had better
cope.)
I tripped across the latter item while investigating a trouble report on
buildfarm member spoonbill. As for the former, there's no evidence that
PQcancel failure is actually involved in spoonbill's problem, but it still
seems like a bad idea to ignore an error return code.
An oversight in commit e710b65c1c56ca7b91f662c63d37ff2e72862a94 allowed
database names beginning with "-" to be treated as though they were secure
command-line switches; and this switch processing occurs before client
authentication, so that even an unprivileged remote attacker could exploit
the bug, needing only connectivity to the postmaster's port. Assorted
exploits for this are possible, some requiring a valid database login,
some not. The worst known problem is that the "-r" switch can be invoked
to redirect the process's stderr output, so that subsequent error messages
will be appended to any file the server can write. This can for example be
used to corrupt the server's configuration files, so that it will fail when
next restarted. Complete destruction of database tables is also possible.
Fix by keeping the database name extracted from a startup packet fully
separate from command-line switches, as had already been done with the
user name field.
The Postgres project thanks Mitsumasa Kondo for discovering this bug,
Kyotaro Horiguchi for drafting the fix, and Noah Misch for recognizing
the full extent of the danger.
Security: CVE-2013-1899
The pg_start_backup() and pg_stop_backup() functions checked the privileges
of the initially-authenticated user rather than the current user, which is
wrong. For example, a user-defined index function could successfully call
these functions when executed by ANALYZE within autovacuum. This could
allow an attacker with valid but low-privilege database access to interfere
with creation of routine backups. Reported and fixed by Noah Misch.
Security: CVE-2013-1901
In commit 0f61d4dd1b4f95832dcd81c9688dac56fd6b5687, I added code to copy up
column width estimates for each column of a subquery. That code supposed
that the subquery couldn't have any output columns that didn't correspond
to known columns of the current query level --- which is true when a query
is parsed from scratch, but the assumption fails when planning a view that
depends on another view that's been redefined (adding output columns) since
the upper view was made. This results in an assertion failure or even a
crash, as per bug #8025 from lindebg. Remove the Assert and instead skip
the column if its resno is out of the expected range.
Now that pg_dump no longer dumps invalid indexes, per commit
683abc73dff549e94555d4020dae8d02f32ed78b, have pg_upgrade also skip
them. Previously pg_upgrade threw an error if invalid indexes existed.
Backpatch to 9.2, 9.1, and 9.0 (where pg_upgrade was added to git)
Windows sometimes gets upset if we rename a large directory and then try
to use the old name quickly, as seen in occasional buildfarm failures.
So we avoid that by building the old version in the intended
destination in the first place instead of renaming it, similar to the
change made for the same reason in commit b7f8465c.
I changed this in commit fd15dba543247eb1ce879d22632b9fdb4c230831, but
missed the fact that the SGML documentation of the function specified
exactly what it did. Well, one of the two places where it's specified
documented that --- probably I looked at the other place and thought
nothing needed to be done. Sync the two places where encode() and
decode() are described.
9.2 uses a kluge representation of "indislive"; we have to account for
that when examining pg_index. Simplest solution is to check indisready
for 9.0 and 9.1 as well; that's harmless though unnecessary, so it's
not worth making a version distinction for.
Fixes oversight in commit 683abc73dff549e94555d4020dae8d02f32ed78b,
as noted by Andres Freund.
Previously, if the postmaster initialized OpenSSL's PRNG (which it will do
when ssl=on in postgresql.conf), the same pseudo-random state would be
inherited by each forked child process. The problem is masked to a
considerable extent if the incoming connection uses SSL encryption, but
when it does not, identical pseudo-random state is made available to
functions like contrib/pgcrypto. The process's PID does get mixed into any
requested random output, but on most systems that still only results in 32K
or so distinct random sequences available across all Postgres sessions.
This might allow an attacker who has database access to guess the results
of "secure" operations happening in another session.
To fix, forcibly reset the PRNG after fork(). Each child process that has
need for random numbers from OpenSSL's generator will thereby be forced to
go through OpenSSL's normal initialization sequence, which should provide
much greater variability of the sequences. There are other ways we might
do this that would be slightly cheaper, but this approach seems the most
future-proof against SSL-related code changes.
This has been assigned CVE-2013-1900, but since the issue and the patch
have already been publicized on pgsql-hackers, there's no point in trying
to hide this commit.
Back-patch to all supported branches.
Marko Kreen
In a heap update, if the old and new tuple were on different pages, and the
new page no longer existed (because it was subsequently truncated away by
vacuum), heap_xlog_update forgot to release the pin on the old buffer. This
bug was introduced by the "Fix multiple problems in WAL replay" patch,
commit 3bbf668de9f1bc172371681e80a4e769b6d014c8 (on master branch).
With full_page_writes=off, this triggered an "incorrect local pin count"
error later in replay, if the old page was vacuumed.
This fixes bug #7969, reported by Yunong Xiao. Backpatch to 9.0, like the
commit that introduced this bug.
Dumping invalid indexes can cause problems at restore time, for example
if the reason the index creation failed was because it tried to enforce
a uniqueness condition not satisfied by the table's data. Also, if the
index creation is in fact still in progress, it seems reasonable to
consider it to be an uncommitted DDL change, which pg_dump wouldn't be
expected to dump anyway.
Back-patch to all active versions, and teach them to ignore invalid
indexes in servers back to 8.2, where the concept was introduced.
Michael Paquier
If you have clusters of different versions pointing to the same tablespace
location, we would incorrectly include all the data belonging to the other
versions, too.
Fixes bug #7986, reported by Sergey Burladyan.
These programs don't work against 9.0 or earlier servers, so check that when
the connection is made. That's better than a cryptic error message you got
before.
Also, these programs won't work with a 9.3 server, because the WAL streaming
protocol was changed in a non-backwards-compatible way. As a general rule,
we don't make any guarantee that an old client will work with a new server,
so check that. However, allow a 9.1 client to connect to a 9.2 server, to
avoid breaking environments that currently work; a 9.1 client happens to
work with a 9.2 server, even though we didn't make any great effort to
ensure that.
This patch is for the 9.1 and 9.2 branches, I'll commit a similar patch to
master later. Although this isn't a critical bug fix, it seems safe enough
to back-patch. The error message you got when connecting to a 9.3devel
server without this patch was cryptic enough to warrant backpatching.
Most (all?) of Russia has moved to what's effectively year-round daylight
savings time, so that the "standard" zone names now mean an hour later
than they used to. Update that, notably changing MSK as per recent
complaint from Sergey Konoplev, but also CHOT, GET, IRKT, KGT, KRAT,
MAGT, NOVT, OMST, VLAT, YAKT, YEKT. The corresponding DST abbreviations
are presumably now obsolete, but I left them in place with their old
definitions, just to reduce any possible breakage from this change.
Also add VOLT (Europe/Volgograd), which for some reason we never had
before, as well as MIST (Antarctica/Macquarie), and fix obsolete
definitions of MAWT, TKT, and WST.
This appears to cause some intermittent file system problems
on Windows 8. Instead, set up the old data directory in its
intended final location to start with.
Doing that results in a broken index entry in PDF output. We had only
a few like that, which is probably why nobody noticed before.
Standardize on putting the <term> first.
Josh Kupershmidt
If the remote database's settings of these GUCs are different from ours,
ambiguous datetime values may be read incorrectly. To fix, temporarily
adopt the remote server's settings while we ingest a query result.
This is not a complete fix, since it doesn't do anything about ambiguous
values in commands sent to the remote server; but there seems little we
can do about that end of it given dblink's entirely textual API for
transmitted commands.
Back-patch to 9.2. The hazard exists in all versions, but this patch
would need more work to apply before 9.2. Given the lack of field
complaints about this issue, it doesn't seem worth the effort at present.
Daniel Farina and Tom Lane
The docs showed that early-January dates can be considered part of the
previous year for week-counting purposes, but failed to say explicitly
that late-December dates can also be considered part of the next year.
Fix that, and add a cross-reference to the "isoyear" field. Per bug
#7967 from Pawel Kobylak.
When RETURNING is specified, ExecDelete would return a virtual-tuple slot
that could contain pointers into an already-unpinned disk buffer. Another
process could change the buffer contents before we get around to using the
data, resulting in garbage results or even a crash. This seems of fairly
low probability, which may explain why there are no known field reports of
the problem, but it's definitely possible. Fix by forcing the result slot
to be "materialized" before we release pin on the disk buffer.
Back-patch to 9.0; in earlier branches there is no bug because
ExecProcessReturning sent the tuple to the destination immediately. Also,
this is already fixed in HEAD as part of the writable-foreign-tables patch
(where the fix is necessary for DELETE RETURNING to work at all with
postgres_fdw).
The previous coding of this function could get into situations where it
would never terminate, because successive passes would re-add EMPTY arcs
that had been removed by the previous pass. Rewrite the function
completely using a new algorithm that is guaranteed to terminate, and
also seems to be usually faster than the old one. Per Tcl bugs 3604074
and 3606683.
Tom Lane and Don Porter
If we were about to enter archive recovery after crash recovery, we scanned
the archive for the latest tli history file, and set the recovery target
timeline to that. However, when we actually tried to read the history file,
we would not fetch the file from the archive, because we were not in archive
recovery yet.
To fix, make readTimeLineHistory and existsTimeLineHistory to always fetch
the file from archive if archive recovery is requested, even if we're not in
archive recovery yet.
Backpatch to 9.2. Mitsumasa KONDO
I missed to returns in the middle of ReadRecord function in my previous fix.
If a WAL file was not found at all during crash recovery, XLogPageRead would
return 'false', and ReadRecord would return without entering archive recovery.
9.2 only. In master, the code is structured differently and does not have this
problem.
Kyotaro HORIGUCHI, Mitsumasa KONDO and me.
formatting.c used locale-dependent case folding rules in some code paths
where the result isn't supposed to be locale-dependent, for example
to_char(timestamp, 'DAY'). Since the source data is always just ASCII
in these cases, that usually didn't matter ... but it does matter in
Turkish locales, which have unusual treatment of "i" and "I". To confuse
matters even more, the misbehavior was only visible in UTF8 encoding,
because in single-byte encodings we used pg_toupper/pg_tolower which
don't have locale-specific behavior for ASCII characters. Fix by providing
intentionally ASCII-only case-folding functions and using these where
appropriate. Per bug #7913 from Adnan Dursun. Back-patch to all active
branches, since it's been like this for a long time.
I fixed this code back in commit 841b4a2d5, but didn't think carefully
enough about the behavior near zero, which meant it improperly rejected
1999-12-31 24:00:00. Per report from Magnus Hagander.
fmgr_sql had been designed on the assumption that the FmgrInfo it's called
with has only query lifespan. This is demonstrably unsafe in connection
with range types, as shown in bug #7881 from Andrew Gierth. Fix things
so that we re-generate the function's cache data if the (sub)transaction
it was made in is no longer active.
Back-patch to 9.2. This might be needed further back, but it's not clear
whether the case can realistically arise without range types, so for now
I'll desist from back-patching further.
