It was always false in single-user mode, in autovacuum workers, and in
background workers. This had no specifically-identified security
consequences, but non-core code or future work might make it
security-relevant. Back-patch to v11 (all supported versions).
Jelte Fennema-Nio. Reported by Jelte Fennema-Nio.
Documentation says it cannot signal "a backend owned by a superuser".
On the contrary, it could signal background workers, including the
logical replication launcher. It could signal autovacuum workers and
the autovacuum launcher. Block all that. Signaling autovacuum workers
and those two launchers doesn't stall progress beyond what one could
achieve other ways. If a cluster uses a non-core extension with a
background worker that does not auto-restart, this could create a denial
of service with respect to that background worker. A background worker
with bugs in its code for responding to terminations or cancellations
could experience those bugs at a time the pg_signal_backend member
chooses. Back-patch to v11 (all supported versions).
Reviewed by Jelte Fennema-Nio. Reported by Hemanth Sandrana and
Mahendrakar Srinivasarao.
Security: CVE-2023-5870
This function implements the standard XMLTest function, which
converts text into xml text nodes. It uses the libxml2 function
xmlEncodeSpecialChars to escape predefined entities (&"<>), so
that those do not cause any conflict when concatenating the text
node output with existing xml documents.
This also adds a note in features.sgml about not supporting
XML(SEQUENCE). The SQL specification defines a RETURNING clause
to a set of XML functions, where RETURNING CONTENT or RETURNING
SEQUENCE can be defined. Since PostgreSQL doesn't support
XML(SEQUENCE) all of these functions operate with an
implicit RETURNING CONTENT.
Author: Jim Jones <jim.jones@uni-muenster.de>
Reviewed-by: Vik Fearing <vik@postgresfriends.org>
Discussion: https://postgr.es/m/86617a66-ec95-581f-8d54-08059cca8885@uni-muenster.de
pg_resetwal had poor test coverage. There are some TAP tests, but
they all run with -n, so they don't actually test the full
functionality. (There is a non-dry-run call of pg_resetwal in the
recovery test suite, but that is incidental.)
This adds a bunch of more tests to test all the different options and
scenarios.
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://www.postgresql.org/message-id/flat/0f3ab4a1-ae80-56e8-3426-6b4a02507687@eisentraut.org
On Windows, GetDataDirectoryCreatePerm() just did nothing. The way
the code in some callers is structured, this is the first function
that tries to access the data directory. So it also ends up the place
that is responsible for reporting that a data directory does not exist
or similar. Therefore, on Windows, these scenarios end up on
potentially completely different code paths.
To unify this, to make testing more consistent across platforms, have
GetDataDirectoryCreatePerm() run the stat() call on Windows as well,
even though it won't do anything with the result. That way, file
system errors are reporting to callers in the same way as on
non-Windows.
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://www.postgresql.org/message-id/15a59bca-0383-183c-9383-0446da9b87e1%40eisentraut.org
recurse_set_operations() uses the parse tree for the group number estimation,
because of the "varno 0" hack. At the same time 2489d76c49 made root->parse
and corresponding parent_root->simple_rte_array[]->subquery distinct copies
of the parse tree, while d3d55ce571 introduced self-join removal replacing
relid of removed relation only in one of the copies.
The present commit fixes this bug by making recurse_set_operations() call
estimate_num_groups() with the copy of the parse tree processed by self-join
removal.
In future, we may think about maintaining just one copy of the parse tree
and/or keeping removed relids as aliases.
Reported-by: Zuming Jiang
Bug: #18170
Discussion: https://postgr.es/m/flat/18170-f1d17bf9a0d58b24%40postgresql.org
Author: Richard Guo, Alexander Korotkov
Reviewed-by: Andrei Lepikhov
In f13eb16485f I made a mistake leading to only man1 being installed. I will
report a bug suggesting that meson warn about mistakes of this sort.
Reported-by: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/ZUU5pRQO6ZUeBsi6@msg.df7cb.de
Backpatch: 16-, where the meson build was introduced
This text left one with the impression that an ON SELECT rule could
be attached to a plain table, which has not been true since commit
264c06820 (meaning the text was already misleading when written,
evidently by me in 96bd67f61). However, it didn't get really bad
until b23cd185f removed the convert-a-table-to-a-view logic, which
had made it possible for scripts that thought they were attaching
ON SELECTs to tables to still work.
Rewrite into a form that makes it clear that an ON SELECT rule
is better regarded as an implementation detail of a view.
Pre-v16, point out that adding ON SELECT to a table actually
converts it to a view.
Per bug #18178 from Joshua Uyehara. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18178-05534d7064044d2d@postgresql.org
cac169d68 adjusted DEFAULT_FDW_TUPLE_COST and that seems to have caused
a test to become unstable on 32-bit machines.
4b14e1871 tried to fix this as originally the plan was flipping between
a Nested Loop and Hash Join. That commit forced the Nested Loop, but
there's still flexibility to push or not push the sort to the remote
server and 32-bit seems to prefer to push and on 64-bit, the costs
prefer not to.
Here let's just turn off enable_sort to significantly encourage the sort
to take place on the remote server.
Reported-by: Michael Paquier, Richard Guo
Discussion: https://postgr.es/m/ZUM2IhA8X2lrG50K@paquier.xyz
As per the preceding commit, GUC APIs generally expose NULL-valued
string variables as empty strings. Extend that policy to
GetConfigOption() and GetConfigOptionResetString(), eliminating
a crash hazard for unwary callers, as well as a fundamental
ambiguity in GetConfigOption()'s API.
No back-patch, since this is an API change and conceivably somebody
somewhere is depending on this corner case.
Xing Guo, Aleksander Alekseev, Tom Lane
Discussion: https://postgr.es/m/CACpMh+AyDx5YUpPaAgzVwC1d8zfOL4JoD-uyFDnNSa1z0EsDQQ@mail.gmail.com
get_explain_guc_options() crashed if a string GUC marked GUC_EXPLAIN
has a NULL boot_val. Nosing around found a couple of other places
that seemed insufficiently cautious about NULL string values, although
those are likely unreachable in practice. Add some commentary
defining the expectations for NULL values of string variables,
in hopes of forestalling future additions of more such bugs.
Xing Guo, Aleksander Alekseev, Tom Lane
Discussion: https://postgr.es/m/CACpMh+AyDx5YUpPaAgzVwC1d8zfOL4JoD-uyFDnNSa1z0EsDQQ@mail.gmail.com
cac169d68 adjusted DEFAULT_FDW_TUPLE_COST and that seems to have caused
a test to become unstable on 32-bit machines. Try to make it stable
again.
Reported-by: Michael Paquier
Discussion: https://postgr.es/m/ZUM2IhA8X2lrG50K@paquier.xyz
Introduce unicode_version(), icu_unicode_version(), and
unicode_assigned().
The latter requires introducing a new lookup table for the Unicode
General Category, which is generated along with the other Unicode
lookup tables.
Discussion: https://postgr.es/m/CA+TgmoYzYR-yhU6k1XFCADeyj=Oyz2PkVsa3iKv+keM8wp-F_A@mail.gmail.com
Reviewed-by: Peter Eisentraut
The logical replication launcher may start apply workers during an
upgrade. This could be the cause of corruptions on a new cluster if
these are able to apply changes before the physical files are copied
over to the new cluster.
The chance of being able to do so is small as pg_upgrade uses its own
port and unix domain directory (the latter is customizable with
--socketdir), but just preventing the launcher to start is safer at the
end, because we are then sure that no changes will be applied. Like
29d0a77fa660 for max_slot_wal_keep_size, this is only set when a cluster
uses v17 or newer.
Author: Vignesh C
Discussion: https://postgr.es/m/CALDaNm2g9ZKf=y8X6z6MsLCuh8WwU-=Q6pLj35NFi2M5BZNS_A@mail.gmail.com
The test missed that custom GUCs need to be ignored from the list of
parameters that can exist in postgresql.conf.sample. This caused the
test to fail on a server where such a module is loaded, when using
EXTRA_INSTALL and TEMP_CONFIG, for instance.
Author: Anton A. Melnikov
Discussion: https://postgr.es/m/fc5509ce-5144-4dac-8d13-21793da44fc5@postgrespro.ru
Backpatch-through: 15
0.01 was unrealistically low as it's the same as the default
cpu_tuple_cost and 10x cheaper than the default parallel_tuple_cost.
It's hard to imagine a situation where fetching a tuple from a foreign
server would be cheaper than fetching one from a parallel worker.
After some experimentation on a loopback server, somewhere between 0.15
and 0.3 seems more realistic. Here we split the difference and set it
to 0.2.
This will cause operations that reduce the number of tuples (e.g.
aggregation) to be more likely to take place on the foreign server.
Adjusting this causes some plan changes in the postgres_fdw regression
tests. This is because penalizing each Path with the additional tuple
costs causes some dilution of the costs of the other operations being
charged for and results in various paths appearing to be closer to the
same costs such that add_path's STD_FUZZ_FACTOR is more likely to see two
paths as costing (fuzzily) the same. This isn't ideal, but it shouldn't
be reason enough to use artificially low costs.
Discussion: https://postgr.es/m/CAApHDvopVjjfh5c1Ed2HRvDdfom2dEpMwwiu5-f1AnmYprJngA@mail.gmail.com
This part of the documentation refers to exceptions as handled by
PL/pgSQL, and using the internal error code is confusing.
Per thinko in 66bde49d96a9.
Reported-by: Euler Taveira, Bruce Momjian
Discussion: https://postgr.es/m/ZUEUnLevXyW7DlCs@momjian.us
Backpatch-through: 11
The documentation includes a section describing how to define custom
LWLocks in extensions using the shmem hooks. However, it has never
mentioned the second, more flexible method based on the following
routines:
- LWLockNewTrancheId() to allocate a tranche ID.
- LWLockRegisterTranche() to associate a name to a tranche ID.
- LWLockInitialize() to initialize a LWLock with a tranche ID.
autoprewarm.c is the only example of extension in the tree that
allocates a LWLock this way.
This commit adds some documentation about all that. While on it, a
comment is added about the need of AddinShmemInitLock. This is required
especially for EXEC_BACKEND builds (aka Windows, normally), as per a
remark from Alexander, because backends can execute shmem initialization
paths concurrently.
Author: Aleksander Alekseev, Michael Paquier
Discussion: https://postgr.es/m/CAJ7c6TPKhFgL+54cdTD9yGpG4+sNcyJ+N1GvQqAxgWENAOa3VA@mail.gmail.com
4b8266415 added a precheck to pgrowlocks() to ensure the given object's
pg_class.relam is HEAP_TABLE_AM_OID, however, that check was put before
another check which was checking if the given object was a partitioned
table. Since the pg_class.relam is always InvalidOid for partitioned
tables, if pgrowlocks() was called passing a partitioned table, then the
"only heap AM is supported" error would be raised instead of the intended
error about the given object being a partitioned table.
Here we simply move the pg_class.relam check to after the check that
verifies that we are in fact working with a normal (non-partitioned)
table.
Reported-by: jian he
Discussion: https://postgr.es/m/CACJufxFaSp_WguFCf0X98951zFVX+dXFnF1mxAb-G3g1HiHOow@mail.gmail.com
Backpatch-through: 12, where 4b8266415 was introduced.
pgstatindex failed with ERRCODE_DATA_CORRUPTED, of the "can't-happen"
class XX. The other functions succeeded on an empty index; they might
have malfunctioned if the failed index build left torn I/O or other
complex state. Report an ERROR in statistics functions pgstatindex,
pgstatginindex, pgstathashindex, and pgstattuple. Report DEBUG1 and
skip all index I/O in maintenance functions brin_desummarize_range,
brin_summarize_new_values, brin_summarize_range, and
gin_clean_pending_list. Back-patch to v11 (all supported versions).
Discussion: https://postgr.es/m/20231001195309.a3@google.com
This prevents false-positive reports about "the first child of leftmost
target page is not leftmost of its level", "block %u is not leftmost"
and "left link/right link pair". They appeared if amcheck ran before
VACUUM cleaned things, after a cluster exited recovery between the
first-stage and second-stage WAL records of a deletion. Back-patch to
v11 (all supported versions).
Reviewed by Peter Geoghegan.
Discussion: https://postgr.es/m/20231005025232.c7.nmisch@google.com
In test_decoding module, when skip_empty_xacts option was specified, add
stream_start/stop for streaming transactional messages. This makes the
handling of transactional messages stream consistent irrespective of
whether skip_empty_xacts option was specified.
Commit 26dd0284b9 made a similar change for non-streaming messages but
forgot to update the streaming cases.
Author: Peter Smith
Reviewed-by: Amit Kapila
Discussion: http://postgr.es/m/OS0PR01MB5716AEBD2988F8F5E9D5985794DFA@OS0PR01MB5716.jpnprd01.prod.outlook.com
When beginning recovery, a LOG is displayed by the startup process to
show which recovery mode will be used depending on the .signal file(s)
set in the data folder, like "standby mode", recovery up to a given
target type and value, or archive recovery.
A different patch is under discussion to simplify the startup code by
requiring the presence of recovery.signal and/or standby.signal when a
backup_label file is read. Delaying a bit this LOG ensures that the
correct recovery mode would be reported, and putting it at this position
does not make it lose its value.
While on it, this commit adds a few comments documenting a bit more the
initial recovery steps and their dependencies, and fixes an incorrect
comment format. This introduces no behavior changes.
Extracted from a larger patch by me.
Reviewed-by: David Steele, Bowen Shi
Discussion: https://postgr.es/m/ZArVOMifjzE7f8W7@paquier.xyz
Commit 536f410111 added links in the ALTER SUBSCRIPTION command page. The
link names used were slightly different from what other logical
replication commands like CREATE SUBSCRIPTION/PUBLICATION have but were
consistent with other docs. This patch changes the link names for all the
parameters to have 'params' word in the CREATE SUBSCRIPTION/PUBLICATION
pages.
Author: Peter Smith
Reviewed-by: Amit Kapila
Discussion: http://postgr.es/m/CAHut%2BPu2S4RdzYKR7H5_E7QYWyq5hB0hL4EFrYbP91Qso62jeg%40mail.gmail.com
When beginning recovery from a base backup by reading a backup_label
file, it may be possible that no checkpoint record is available
depending on the method used when the case backup was taken, which would
prevent recovery from beginning. In this case, the FATAL messages
issued, initially added by c900c15269f0f, mentioned recovery.signal as
an option to do recovery but not standby.signal. Let's add it as an
available option, for clarity.
Per suggestion from Bowen Shi, extracted from a larger patch by me.
Author: Michael Paquier
Discussion: https://postgr.es/m/CAM_vCudkSjr7NsNKSdjwtfAm9dbzepY6beZ5DP177POKy8=2aw@mail.gmail.com
Historically, the statistics of the checkpointer have been always part
of pg_stat_bgwriter. This commit removes a few columns from
pg_stat_bgwriter, and introduces pg_stat_checkpointer with equivalent,
renamed columns (plus a new one for the reset timestamp):
- checkpoints_timed -> num_timed
- checkpoints_req -> num_requested
- checkpoint_write_time -> write_time
- checkpoint_sync_time -> sync_time
- buffers_checkpoint -> buffers_written
The fields of PgStat_CheckpointerStats and its SQL functions are renamed
to match with the new field names, for consistency. Note that
background writer and checkpointer have been split into two different
processes in commits 806a2aee3791 and bf405ba8e460. The pgstat
structures were already split, making this change straight-forward.
Bump catalog version.
Author: Bharath Rupireddy
Reviewed-by: Bertrand Drouvot, Andres Freund, Michael Paquier
Discussion: https://postgr.es/m/CALj2ACVxX2ii=66RypXRweZe2EsBRiPMj0aHfRfHUeXJcC7kHg@mail.gmail.com
