The parser code that transformed VALUES from row-oriented to
column-oriented lists failed if there were zero columns.
You can't write that straightforwardly (though probably you
should be able to), but the case can be reached by expanding
a "tab.*" reference to a zero-column table.
Per bug #17477 from Wang Ke. Back-patch to all supported branches.
Discussion: https://postgr.es/m/17477-0af3c6ac6b0a6ae0@postgresql.org
This reverts commit eafdf9de06
and its back-branch counterparts. Corey Huinker pointed out that
we'd discussed this exact change back in 2016 and rejected it,
on the grounds that there's at least one usage pattern with LIMIT
where an infinite endpoint can usefully be used. Perhaps that
argument needs to be re-litigated, but there's no time left before
our back-branch releases. To keep our options open, restore the
status quo ante; if we do end up deciding to change things, waiting
one more quarter won't hurt anything.
Rather than just doing a straight revert, I added a new test case
demonstrating the usage with LIMIT. That'll at least remind us of
the issue if we forget again.
Discussion: https://postgr.es/m/3603504.1652068977@sss.pgh.pa.us
Discussion: https://postgr.es/m/CADkLM=dzw0Pvdqp5yWKxMd+VmNkAMhG=4ku7GnCZxebWnzmz3Q@mail.gmail.com
It intended to, but did not, achieve this. Adopt the new standard of
setting user ID just after locking the relation. Back-patch to v10 (all
supported versions).
Reviewed by Simon Riggs. Reported by Alvaro Herrera.
Security: CVE-2022-1552
When a feature enumerates relations and runs functions associated with
all found relations, the feature's user shall not need to trust every
user having permission to create objects. BRIN-specific functionality
in autovacuum neglected to account for this, as did pg_amcheck and
CLUSTER. An attacker having permission to create non-temp objects in at
least one schema could execute arbitrary SQL functions under the
identity of the bootstrap superuser. CREATE INDEX (not a
relation-enumerating operation) and REINDEX protected themselves too
late. This change extends to the non-enumerating amcheck interface.
Back-patch to v10 (all supported versions).
Sergey Shinderuk, reviewed (in earlier versions) by Alexander Lakhin.
Reported by Alexander Lakhin.
Security: CVE-2022-1552
If a cluster is promoted (aka the control file shows a state different
than DB_IN_ARCHIVE_RECOVERY) while CreateRestartPoint() is still
processing, this function could miss an update of the control file for
"checkPoint" and "checkPointCopy" but still do the recycling and/or
removal of the past WAL segments, assuming that the to-be-updated LSN
values should be used as reference points for the cleanup. This causes
a follow-up restart attempting crash recovery to fail with a PANIC on a
missing checkpoint record if the end-of-recovery checkpoint triggered by
the promotion did not complete while the cluster abruptly stopped or
crashed before the completion of this checkpoint. The PANIC would be
caused by the redo LSN referred in the control file as located in a
segment already gone, recycled by the previous restartpoint with
"checkPoint" out-of-sync in the control file.
This commit fixes the update of the control file during restartpoints so
as "checkPoint" and "checkPointCopy" are updated even if the cluster has
been promoted while a restartpoint is running, to be on par with the set
of WAL segments actually recycled in the end of CreateRestartPoint().
This problem exists in all the stable branches. However, commit
7ff23c6, by removing the last call of CreateCheckPoint() from the
startup process, has made this bug much easier to reason about as
concurrent checkpoints are not possible anymore. No backpatch is done
yet, mostly out of caution from me as a point release is close by, but
we need to think harder about the case of concurrent checkpoints at
promotion if the bgwriter is not considered as running by the startup
process in ~v14, so this change is done only on HEAD for the moment.
Reported-by: Fujii Masao, Rui Zhao
Author: Kyotaro Horiguchi
Reviewed-by: Nathan Bossart, Michael Paquier
Discussion: https://postgr.es/m/20220316.102444.2193181487576617583.horikyota.ntt@gmail.com
Commits 4eb21763 and b74e94dc introduced a way to force every backend to
close all relation files, to fix an ancient Windows-only bug.
This commit extends that behavior to all operating systems and adds
a couple of extra barrier points, to fix a totally different class of
bug: the reuse of relfilenodes in scenarios that have no other kind of
cache invalidation to prevent file descriptor mix-ups.
In all releases, data corruption could occur when you moved a database
to another tablespace and then back again. Despite that, no back-patch
for now as the infrastructure required is too new and invasive. In
master only, since commit aa010514, it could also happen when using
CREATE DATABASE with a user-supplied OID or via pg_upgrade.
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20220209220004.kb3dgtn2x2k2gtdm%40alap3.anarazel.de
With sufficiently bad luck, it was possible for IssuePendingWritebacks()
to reopen a file after we'd processed PROCSIGNAL_BARRIER_SMGRRELEASE and
before the file was unlinked by some other backend. That left a small
hole in commit 4eb21763's plan to fix all spurious errors from DROP
TABLESPACE and similar on Windows.
Fix by closing md.c's segments, instead of just closing fd.c's
descriptors, and then teaching smgrwriteback() not to open files that
aren't already open.
Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/20220209220004.kb3dgtn2x2k2gtdm%40alap3.anarazel.de
Since 6bc8ef0b7f, the maximum number
of backends can't change as background workers are registered, but
these comments still reflect the way things worked prior to that.
Also, per recent discussion, some modules call SetConfigOption()
from _PG_init(). It's not entirely clear to me whether we want to
regard that as a fully supported operation, but since we know it's
a thing that happens, it at least deserves a mention in the comments,
so add that.
Nathan Bossart, reviewed by Anton A. Melnikov
Discussion: http://postgr.es/m/20220419154658.GA2487941@nathanxps13
The PXE_CIPHER_INIT error is used to report initialization errors, so
appending a questionmark to the error isn't entirely accurate (using a
space before the questionmark doubly so).
Discussion: https://postgr.es/m/C89D932C-501E-4473-9750-638CFCD9095E@yesql.se
Report OpenSSL errors during initialization as PXE_CIPHER_INIT since
that's just what they were, and not generic unknown errors. This also
removes the last users of the generic error, and thus it can be removed.
Discussion: http://postgr.es/m/C89D932C-501E-4473-9750-638CFCD9095E@yesql.se
Setting up an EVP context for ciphers banned under FIPS generate
two OpenSSL errors in the queue, and as we only consume one from
the queue the other is at the head for the next invocation:
postgres=# select md5('foo');
ERROR: could not compute MD5 hash: unsupported
postgres=# select md5('foo');
ERROR: could not compute MD5 hash: initialization error
Clearing the error queue when creating the context ensures that
we don't pull in an error from an earlier operation.
Discussion: https://postgr.es/m/C89D932C-501E-4473-9750-638CFCD9095E@yesql.se
SubqueryScan was always getting labeled with a rowcount estimate
appropriate for non-parallel cases. However, nodes that are
underneath a Gather should be treated as processing only one
worker's share of the rows, whether the particular node is explicitly
parallel-aware or not. Most non-scan-level node types get this
right automatically because they base their rowcount estimate on
that of their input sub-Path(s). But SubqueryScan didn't do that,
instead using the whole-relation rowcount estimate as if it were
a non-parallel-aware scan node. If there is a parallel-aware node
below the SubqueryScan, this is wrong, and it results in inflating
the cost estimates for nodes above the SubqueryScan, which can cause
us to not choose a parallel plan, or choose a silly one --- as indeed
is visible in the one regression test whose results change with this
patch. (Although that plan tree appears to contain no SubqueryScans,
there were some in it before setrefs.c deleted them.)
To fix, use path->subpath->rows not baserel->tuples as the number
of input tuples we'll process. This requires estimating the quals'
selectivity afresh, which is slightly annoying; but it shouldn't
really add much cost thanks to the caching done in RestrictInfo.
This is pretty clearly a bug fix, but I'll refrain from back-patching
as people might not appreciate plan choices changing in stable branches.
The fact that it took us this long to identify the bug suggests that
it's not a major problem.
Per report from bucoo, though this is not his proposed patch.
Discussion: https://postgr.es/m/202204121457159307248@sohu.com
The test for lz4.h used AC_CHECK_HEADERS, but nothing was using the
resulting symbol HAVE_LZ4_H. Change this to use AC_CHECK_HEADER
instead. This was probably an oversight, seeing that the nearby
similar tests do this correctly.
The testclient and uri-regress programs in the libpq test suite had
quite generic names which didn't convey much meaning. Since they are
installed as part of the MSVC test runs, ensure that their purpose
is a little bit clearer by renaming with a libpq_ prefix. While at
it rename uri-regress to uri_regress to avoid mixing dash and under-
score in the same filename.
Reported-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20220501080706.GA1542365@rfd.leadboat.com
The tests added in 9f8a050f68 failed nearly reliably on FreeBSD in CI, and
occasionally on the buildfarm. That turns out to be caused not by a bug in the
test, but by a longstanding bug in recovery conflict handling.
The standby timeout handler, used by ResolveRecoveryConflictWithBufferPin(),
executed SendRecoveryConflictWithBufferPin() inside a signal handler. A bad
idea, because the deadlock timeout handler (or a spurious latch set) could
have interrupted ProcWaitForSignal(). If unlucky that could cause a
self-deadlock on ProcArrayLock, if the deadlock check is in
SendRecoveryConflictWithBufferPin()->CancelDBBackends().
To fix, set a flag in StandbyTimeoutHandler(), and check the flag in
ResolveRecoveryConflictWithBufferPin().
Subsequently the recovery conflict tests will be backpatched.
Discussion: https://postgr.es/m/20220413002626.udl7lll7f3o7nre7@alap3.anarazel.de
Backpatch: 10-
The recovery conflict tests added in 9f8a050f68 surfaced a bug in the
interaction between buffer pin and deadlock recovery conflicts. To make sure
that the bugfix won't break deadlock conflict detection, add a test for that
scenario.
031_recovery_conflict.pl will later be backpatched, with this included.
Discussion: https://postgr.es/m/20220413002626.udl7lll7f3o7nre7@alap3.anarazel.de
Instability in the test for pg_walinspect revealed that
pg_get_wal_records_info_till_end_of_wal(x) would try to decode all the
records with a start LSN earlier than the flush LSN, even though that
might include a partial record at the end of the range. In that case,
read_local_xlog_page_no_wait() would return NULL when it tried to read
past the flush LSN, which would be interpreted as an error by the
caller. That caused a test failure only on a BF animal that had been
restarted recently, but could be expected to happen in the wild quite
easily depending on the alignment of various parameters.
Fix by using private data in read_local_xlog_page_no_wait() to signal
end-of-wal to the caller, so that it can be properly distinguished
from a real error.
Discussion: https://postgr.es/m/Ymd/e5eeZMNAkrXo%40paquier.xyz
Discussion: https://postgr.es/m/111657.1650910309@sss.pgh.pa.us
Authors: Thomas Munro, Bharath Rupireddy.
I noticed that plpgsql would allow assignment of a new value to a
variable even when that variable is marked CONSTANT, if the variable
is used as an output parameter in CALL or is a refcursor variable
that OPEN assigns a new value to. Fix these oversights.
In the CALL case, the check has to be done at runtime because we
cannot know at parse time which parameters are OUT parameters.
For OPEN, it seems best to likewise enforce at runtime because
then we needn't throw error if the variable has a nonnull value
(since OPEN will only try to overwrite a null value).
Although this is surely a bug fix, no back-patch: it seems unlikely
that anyone would thank us for breaking formerly-working code in
minor releases.
Discussion: https://postgr.es/m/214453.1651182729@sss.pgh.pa.us
mark_async_capable_plan(), which is called from create_append_plan() to
determine whether subplans are async-capable, failed to take into
account that the given subplan created from a given subpath might
include a gating Result node if the subpath is a SubqueryScanPath or
ForeignPath, causing a segmentation fault there when the subplan created
from a SubqueryScanPath includes the Result node, or causing
ExecAsyncRequest() to throw an error about an unrecognized node type
when the subplan created from a ForeignPath includes the Result node,
because in the latter case the Result node was unintentionally
considered as async-capable, but we don't currently support executing
Result nodes asynchronously. Fix by modifying mark_async_capable_plan()
to disable asynchronous execution in such cases. Also, adjust code in
the ProjectionPath case in mark_async_capable_plan(), for consistency
with other cases, and adjust/improve comments there.
is_async_capable_path() added in commit 27e1f1456, which was rewritten
to mark_async_capable_plan() in a later commit, has the same issue,
causing the error at execution mentioned above, so back-patch to v14
where the aforesaid commit went in.
Per report from Justin Pryzby.
Etsuro Fujita, reviewed by Zhihong Yu and Justin Pryzby.
Discussion: https://postgr.es/m/20220408124338.GK24419%40telsasoft.com
This reverts commits 2c902bb and ccfbd92. Per buildfarm members
kestrel, rorqual and calliphoridae, the assertions checking that a TLI
history file should not exist when created by a WAL receiver have been
failing, and switching to durable_rename() over durable_rename_excl()
would cause the newest TLI history file to overwrite the existing one.
We need to think harder about such cases, so revert the new logic for
now.
Note that all the failures have been reported in the test
025_stuck_on_old_timeline.
Discussion: https://postgr.es/m/511362.1651116498@sss.pgh.pa.us
ccfbd92 has replaced all existing in-core callers of this function in
favor of durable_rename(). durable_rename_excl() is by nature unsafe on
crashes happening at the wrong time, so just remove it.
Author: Nathan Bossart
Reviewed-by: Robert Haas, Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/20220407182954.GA1231544@nathanxps13
durable_rename_excl() attempts to avoid overwriting any existing files
by using link() and unlink(), falling back to rename() on some platforms
(e.g., Windows where link() followed by unlink() is not concurrent-safe,
see 909b449). Most callers of durable_rename_excl() use it just in case
there is an existing file, but it happens that for all of them we never
expect a target file to exist (WAL segment recycling, creation of
timeline history file and basic_archive).
basic_archive used durable_rename_excl() to avoid overwriting an archive
concurrently created by another server. Now, there is a stat() call to
avoid overwriting an existing archive a couple of lines above, so note
that this change opens a small TOCTOU window in this module between the
stat() call and durable_rename().
Furthermore, as mentioned in the top comment of durable_rename_excl(),
this routine can result in multiple hard links to the same file and data
corruption, with two or more links to the same file in pg_wal/ if a
crash happens before the unlink() call during WAL recycling.
Specifically, this would produce links to the same file for the current
WAL file and the next one because the half-recycled WAL file was
re-recycled during crash recovery of a follow-up cluster restart.
This change replaces all calls to durable_rename_excl() with
durable_rename(). This removes the protection against accidentally
overwriting an existing file, but some platforms are already living
without it, and all those code paths never expect an existing file (a
couple of assertions are added to check after that, in case).
This is a bug fix, but knowing the unlikeliness of the problem involving
one of more crashes at an exceptionally bad moment, no backpatch is
done. This could be revisited in the future.
Author: Nathan Bossart
Reviewed-by: Robert Haas, Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/20220407182954.GA1231544@nathanxps13
Unlike existing WRITE_*_ARRAY macros, WRITE_INDEX_ARRAY needs to
handle the case that the field is NULL. We already have the
convention to print NULL fields as "<>", so we do that here as well.
There is currently no corresponding read function for this, so reading
this back in is not implemented, but it could be if needed.
Reported-by: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/CAMbWs4-LN%3DbF8f9eU2R94dJtF54DfDvBq%2BovqHnOQqbinYDrUw%40mail.gmail.com
This commit adds two isolation tests for CLUSTER, using:
- A normal table, making sure that CLUSTER blocks and completes if the
table is locked by a concurrent session.
- A partitioned table with a partition owned by a different user. If
the partitioned table is locked by a concurrent session, CLUSTER on the
partitioned table should block. If the partition owned by a different
user is locked, CLUSTER on its partitioned table should complete and
skip the partition. 3f19e17 has added an early check to ignore such a
partition with a SQL regression test, but this was not checking that
CLUSTER should not block.
Discussion: https://postgr.es/m/YlqveniXn9AI6RFZ@paquier.xyz
For some reason by default the mingw C Runtime takes it upon itself to
expand program arguments that look like shell globbing characters. That
has caused much scratching of heads and mis-attribution of the causes of
some TAP test failures, so stop doing that.
This removes an inconsistency with Windows binaries built with MSVC,
which have no such behaviour.
Per suggestion from Noah Misch.
Backpatch to all live branches.
Discussion: https://postgr.es/m/20220423025927.GA1274057@rfd.leadboat.com
Another test is constructed on top of regression tests, which does not
work correctly with unlogged tables. For now, cope with that by making
sure no unlogged table is left behind.
Per buildfarm pink after 4fb5c794e5.
Several places didn't do it, and in many cases it didn't matter because
it would be a small allocation in a short-lived context; but other
places may accumulate a few (for example, in CreateDatabaseUsingFileCopy,
one per tablespace). In most databases this is highly unlikely to be
very serious either, but it seems better to make the code consistent in
case there's future copy-and-paste.
The only case of actual concern seems to be the aforementioned routine,
which is new with commit 9c08aea6a3, so there's no need to backpatch.
As pointed out by Coverity.
This function looks for a reference to the recursive WITH CTE,
but it checked only the CTE name not ctelevelsup, so that it could
seize on a lower CTE that happened to have the same name. This
would result in planner failures later, either weird errors such as
"could not find attribute 2 in subquery targetlist", or crashes
or assertion failures. The code also merely Assert'ed that it found
a matching entry, which is not guaranteed at all by the parser.
Per bugs #17320 and #17318 from Zhiyong Wu.
Thanks to Kyotaro Horiguchi for investigation.
Discussion: https://postgr.es/m/17320-70e37868182512ab@postgresql.org
Discussion: https://postgr.es/m/17318-2eb65a3a611d2368@postgresql.org
Tom Lane
Noah Misch
Peter Eisentraut
Michael Paquier
Thomas Munro
Robert Haas
Daniel Gustafsson
Andres Freund
Etsuro Fujita
Jeff Davis
Andrew Dunstan
John Naylor
Alvaro Herrera