Fix multixact backwards-compatibility with CHECKPOINT race condition
If a CHECKPOINT record with nextMulti N is written to the WAL before
the CREATE_ID record for N, and N happens to be the first multixid on
an offset page, the backwards compatibility logic to tolerate WAL
generated by older minor versions (before commit 789d65364c) failed to
compensate for the missing XLOG_MULTIXACT_ZERO_OFF_PAGE record. In
that case, the latest_page_number was initialized at the start of WAL
replay to the page for nextMulti from the CHECKPOINT record, even if
we had not seen the CREATE_ID record for that multixid yet, which
fooled the backwards compatibility logic to think that the page was
already initialized.
To fix, track the last XLOG_MULTIXACT_ZERO_OFF_PAGE that we've seen
separately from latest_page_number. If we haven't seen any
XLOG_MULTIXACT_ZERO_OFF_PAGE records yet, use
SimpleLruDoesPhysicalPageExist() to check if the page needs to be
initialized.
Tom Lane [Sun, 22 Mar 2026 22:06:48 +0000 (18:06 -0400)]
Fix finalization of decompressor astreamers.
Send the correct amount of data to the next astreamer, not the
whole allocated buffer size. This bug escaped detection because
in present uses the next astreamer is always a tar-file parser
which is insensitive to trailing garbage. But that may not
be true in future uses.
Author: Andrew Dunstan <andrew@dunslane.net> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2178517.1774064942@sss.pgh.pa.us
Backpatch-through: 15
Fujii Masao [Mon, 16 Mar 2026 23:10:20 +0000 (08:10 +0900)]
Fix WAL flush LSN used by logical walsender during shutdown
Commit 6eedb2a5fd8 made the logical walsender call
XLogFlush(GetXLogInsertRecPtr()) to ensure that all pending WAL is flushed,
fixing a publisher shutdown hang. However, if the last WAL record ends at
a page boundary, GetXLogInsertRecPtr() can return an LSN pointing past
the page header, which can cause XLogFlush() to report an error.
A similar issue previously existed in the GiST code. Commit b1f14c96720
introduced GetXLogInsertEndRecPtr(), which returns a safe WAL insertion end
location (returning the start of the page when the last record ends at a page
boundary), and updated the GiST code to use it with XLogFlush().
This commit fixes the issue by making the logical walsender use
XLogFlush(GetXLogInsertEndRecPtr()) when flushing pending WAL during shutdown.
Tomas Vondra [Sat, 14 Mar 2026 14:24:37 +0000 (15:24 +0100)]
Tighten asserts on ParallelWorkerNumber
The comment about ParallelWorkerNumbr in parallel.c says:
In parallel workers, it will be set to a value >= 0 and < the number
of workers before any user code is invoked; each parallel worker will
get a different parallel worker number.
However asserts in various places collecting instrumentation allowed
(ParallelWorkerNumber == num_workers). That would be a bug, as the value
is used as index into an array with num_workers entries.
Fixed by adjusting the asserts accordingly. Backpatch to all supported
versions.
Tomas Vondra [Fri, 13 Mar 2026 21:42:29 +0000 (22:42 +0100)]
Use GetXLogInsertEndRecPtr in gistGetFakeLSN
The function used GetXLogInsertRecPtr() to generate the fake LSN. Most
of the time this is the same as what XLogInsert() would return, and so
it works fine with the XLogFlush() call. But if the last record ends at
a page boundary, GetXLogInsertRecPtr() returns LSN pointing after the
page header. In such case XLogFlush() fails with errors like this:
ERROR: xlog flush request 0/01BD2018 is not satisfied --- flushed only to 0/01BD2000
Such failures are very hard to trigger, particularly outside aggressive
test scenarios.
Fixed by introducing GetXLogInsertEndRecPtr(), returning the correct LSN
without skipping the header. This is the same as GetXLogInsertRecPtr(),
except that it calls XLogBytePosToEndRecPtr().
Initial investigation by me, root cause identified by Andres Freund.
This is a long-standing bug in gistGetFakeLSN(), probably introduced by c6b92041d38 in PG13. Backpatch to all supported versions.
Reported-by: Peter Geoghegan <pg@bowt.ie> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/vf4hbwrotvhbgcnknrqmfbqlu75oyjkmausvy66ic7x7vuhafx@e4rvwavtjswo
Backpatch-through: 14
Michael Paquier [Fri, 13 Mar 2026 07:06:49 +0000 (16:06 +0900)]
xml2: Fix failure with xslt_process() under -fsanitize=undefined
The logic of xslt_process() has never considered the fact that
xsltSaveResultToString() would return NULL for an empty string (the
upstream code has always done so, with a string length of 0). This
would cause memcpy() to be called with a NULL pointer, something
forbidden by POSIX.
Like 46ab07ffda9d and similar fixes, this is backpatched down to all the
supported branches, with a test case to cover this scenario. An empty
string has been always returned in xml2 in this case, based on the
history of the module, so this is an old issue.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/c516a0d9-4406-47e3-9087-5ca5176ebcf9@gmail.com
Backpatch-through: 14
Fujii Masao [Mon, 9 Mar 2026 09:24:41 +0000 (18:24 +0900)]
doc: Document IF NOT EXISTS option for ALTER FOREIGN TABLE ADD COLUMN.
Commit 2cd40adb85d added the IF NOT EXISTS option to ALTER TABLE ADD COLUMN.
This also enabled IF NOT EXISTS for ALTER FOREIGN TABLE ADD COLUMN,
but the ALTER FOREIGN TABLE documentation was not updated to mention it.
This commit updates the documentation to describe the IF NOT EXISTS option for
ALTER FOREIGN TABLE ADD COLUMN.
While updating that section, also this commit clarifies that the COLUMN keyword
is optional in ALTER FOREIGN TABLE ADD/DROP COLUMN. Previously, part of
the documentation could be read as if COLUMN were required.
This commit adds regression tests covering these ALTER FOREIGN TABLE syntaxes.
Backpatch to all supported versions.
Suggested-by: Fujii Masao <masao.fujii@gmail.com>
Author: Chao Li <lic@highgo.com> Reviewed-by: Robert Treat <rob@xzilla.net> Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CAHGQGwFk=rrhrwGwPtQxBesbT4DzSZ86Q3ftcwCu3AR5bOiXLw@mail.gmail.com
Backpatch-through: 14
Michael Paquier [Mon, 9 Mar 2026 04:46:35 +0000 (13:46 +0900)]
Fix size underestimation of DSA pagemap for odd-sized segments
When make_new_segment() creates an odd-sized segment, the pagemap was
only sized based on a number of usable_pages entries, forgetting that a
segment also contains metadata pages, and that the FreePageManager uses
absolute page indices that cover the entire segment. This
miscalculation could cause accesses to pagemap entries to be out of
bounds. During subsequent reuse of the allocated segment, allocations
landing on pages with indices higher than usable_pages could cause
out-of-bounds pagemap reads and/or writes. On write, 'span' pointers
are stored into the data area, corrupting the allocated objects. On
read (aka during a dsa_free), garbage is interpreted as a span pointer,
typically crashing the server in dsa_get_address().
The normal geometric path correctly sizes the pagemap for all pages in
the segment. The odd-sized path needs to do the same, but it works
forward from usable_pages rather than backward from total_size.
This commit fixes the sizing of the odd-sized case by adding pagemap
entries for the metadata pages after the initial metadata_bytes
calculation, using an integer ceiling division to compute the exact
number of additional entries needed in one go, avoiding any iteration in
the calculation.
An assertion is added in the code path for odd-sized segments, ensuring
that the pagemap includes the metadata area, and that the result is
appropriately sized.
This problem would show up depending on the size requested for the
allocation of a DSA segment. The reporter has noticed this issue when a
parallel hash join makes a DSA allocation large enough to trigger the
odd-sized segment path, but it could happen for anything that does a DSA
allocation.
A regression test is added to test_dsa, down to v17 where the test
module has been introduced. This adds a set of cheap tests to check the
problem, the new assertion being useful for this purpose. Sami has
proposed a test that took a longer time than what I have done here; the
test committed is faster and good enough to check the odd-sized
allocation path.
Author: Paul Bunn <paul.bunn@icloud.com> Reviewed-by: Sami Imseih <samimseih@gmail.com> Reviewed-by: Chao Li <li.evan.chao@gmail.com> Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/044401dcabac$fe432490$fac96db0$@icloud.com
Backpatch-through: 14
Fujii Masao [Fri, 6 Mar 2026 07:43:40 +0000 (16:43 +0900)]
Fix publisher shutdown hang caused by logical walsender busy loop.
Previously, when logical replication was running, shutting down
the publisher could cause the logical walsender to enter a busy loop
and prevent the publisher from completing shutdown.
During shutdown, the logical walsender waits for all pending WAL
to be written out. However, some WAL records could remain unflushed,
causing the walsender to wait indefinitely.
The issue occurred because the walsender used XLogBackgroundFlush() to
flush pending WAL. This function does not guarantee that all WAL is written.
For example, WAL generated by a transaction without an assigned
transaction ID that aborts might not be flushed.
This commit fixes the bug by making the logical walsender call XLogFlush()
instead, ensuring that all pending WAL is written and preventing
the busy loop during shutdown.
Tom Lane [Thu, 5 Mar 2026 19:43:21 +0000 (14:43 -0500)]
Exit after fatal errors in client-side compression code.
It looks like whoever wrote the astreamer (nee bbstreamer) code
thought that pg_log_error() is equivalent to elog(ERROR), but
it's not; it just prints a message. So all these places tried to
continue on after a compression or decompression error return,
with the inevitable result being garbage output and possibly
cascading error messages. We should use pg_fatal() instead.
These error conditions are probably pretty unlikely in practice,
which no doubt accounts for the lack of field complaints.
Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/1531718.1772644615@sss.pgh.pa.us
Backpatch-through: 15
Fix handling of updated tuples in the MERGE statement
This branch missed the IsolationUsesXactSnapshot() check. That led to EPQ on
repeatable read and serializable isolation levels. This commit fixes the
issue and provides a simple isolation check for that. Backpatch through v15
where MERGE statement was introduced.
Reported-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/CAPpHfdvzZSaNYdj5ac-tYRi6MuuZnYHiUkZ3D-AoY-ny8v%2BS%2Bw%40mail.gmail.com
Author: Tender Wang <tndrwang@gmail.com> Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Backpatch-through: 15
Fujii Masao [Thu, 5 Mar 2026 03:55:52 +0000 (12:55 +0900)]
doc: Clarify that COLUMN is optional in ALTER TABLE ... ADD/DROP COLUMN.
In ALTER TABLE ... ADD/DROP COLUMN, the COLUMN keyword is optional. However,
part of the documentation could be read as if COLUMN were required, which may
mislead users about the command syntax.
This commit updates the ALTER TABLE documentation to clearly state that
COLUMN is optional for ADD and DROP.
Also this commit adds regression tests covering ALTER TABLE ... ADD/DROP
without the COLUMN keyword.
Backpatch to all supported versions.
Author: Chao Li <lic@highgo.com> Reviewed-by: Robert Treat <rob@xzilla.net> Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CAEoWx2n6ShLMOnjOtf63TjjgGbgiTVT5OMsSOFmbjGb6Xue1Bw@mail.gmail.com
Backpatch-through: 14
Michael Paquier [Thu, 5 Mar 2026 01:06:05 +0000 (10:06 +0900)]
Fix rare instability in recovery TAP test 004_timeline_switch
This fixes a problem similar to ad8c86d22cbd. In this case, the test
could fail under the following circumstances:
- The primary is stopped with teardown_node(), meaning that it may not
be able to send all its WAL records to standby_1 and standby_2.
- If standby_2 receives more records than standby_1, attempting to
reconnect standby_2 to the promoted standby_1 would fail because of a
timeline fork.
This race condition is fixed with a simple trick: instead of tearing
down the primary, it is stopped cleanly so as all the WAL records of the
primary are received and flushed by both standby_1 and standby_2. Once
we do that, there is no need for a wait_for_catchup() before stopping
the node. The test wants to check that a timeline jump can be achieved
when reconnecting a standby to a promoted standby in the same cluster,
hence an immediate stop of the primary is not required.
This failure is harder to reach than the previous instability of
009_twophase, still the buildfarm has been able to detect this failure
at least once. I have tried Alexander Lakhin's test trick with the
bgwriter and very aggressive standby snapshots, but I could not
reproduce it directly. It is reachable, as the buildfarm has proved.
Backpatch down to all supported branches, and this problem can lead to
spurious failures in the buildfarm.
Tom Lane [Wed, 4 Mar 2026 17:08:37 +0000 (12:08 -0500)]
Fix yet another bug in archive streamer with LZ4 decompression.
The code path in astreamer_lz4_decompressor_content() that updated
the output pointers when the output buffer isn't full was wrong.
It advanced next_out by bytes_written, which could include previous
decompression output not just that of the current cycle. The
correct amount to advance is out_size. While at it, make the
output pointer updates look more like the input pointer updates.
This bug is pretty hard to reach, as it requires consecutive
compression frames that are too small to fill the output buffer.
pg_dump could have produced such data before 66ec01dc4, but
I'm unsure whether any files we use astreamer with would be
likely to contain problematic data.
Author: Chao Li <lic@highgo.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/0594CC79-1544-45DD-8AA4-26270DE777A7@gmail.com
Backpatch-through: 15
Michael Paquier [Wed, 4 Mar 2026 07:31:01 +0000 (16:31 +0900)]
Fix rare instability in recovery TAP test 009_twophase
The phase of the test where we want to check that 2PC transactions
prepared on a primary can be committed on a promoted standby relied on
an immediate stop of the primary. This logic has a race condition: it
could be possible that some records (most likely standby snapshot
records) are generated on the primary before it finishes its shutdown,
without the promoted standby know about them. When the primary is
recycled as new standby, the test could fail because of a timeline fork
as an effect of these extra records.
This fix takes care of the instability by doing a clean stop of the
primary instead of a teardown (aka immediate stop), so as all records
generated on the primary are sent to the promoted standby and flushed
there. There is no need for a teardown of the primary in this test
scenario: the commit of 2PC transactions on a promoted standby do not
care about the state of the primary, only of the standby.
This race is very hard to hit in practice, even slow buildfarm members
like skink have a very low rate of reproduction. Alexander Lakhin has
come up with a recipe to improve the reproduction rate a lot:
- Enable -DWAL_DEBUG.
- Patch the bgwriter so as standby snapshots are generated every
milliseconds.
- Run 009_twophase tests under heavy parallelism.
With this method, the failure appears after a couple of iterations.
With the fix in place, I have been able to run more than 50 iterations
of the parallel test sequence, without seeing a failure.
Issue introduced in 30820982b295, due to a copy-pasto coming from the
surrounding tests. Thanks also to Hayato Kuroda for digging into the
details of the failure. He has proposed a fix different than the one of
this commit. Unfortunately, it relied on injection points, feature only
available in v17. The solution of this commit is simpler, and can be
applied to v14~v16.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/b0102688-6d6c-c86a-db79-e0e91d245b1a@gmail.com
Backpatch-through: 14
Nathan Bossart [Mon, 2 Mar 2026 19:12:25 +0000 (13:12 -0600)]
basic_archive: Allow archive directory to be missing at startup.
Presently, the GUC check hook for basic_archive.archive_directory
checks that the specified directory exists. Consequently, if the
directory does not exist at server startup, archiving will be stuck
indefinitely, even if it appears later. To fix, remove this check
from the hook so that archiving will resume automatically once the
directory is present. basic_archive must already be prepared to
deal with the directory disappearing at any time, so no additional
special handling is required.
Reported-by: Олег Самойлов <splarv@ya.ru> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Fujii Masao <masao.fujii@gmail.com> Reviewed-by: Sergei Kornilov <sk@zsrv.org>
Discussion: https://postgr.es/m/73271769675212%40mail.yandex.ru
Backpatch-through: 15
Tom Lane [Mon, 2 Mar 2026 16:14:58 +0000 (11:14 -0500)]
In pg_dumpall, don't skip role GRANTs with dangling grantor OIDs.
In commits 29d75b25b et al, I made pg_dumpall's dumpRoleMembership
logic treat a dangling grantor OID the same as dangling role and
member OIDs: print a warning and skip emitting the GRANT. This wasn't
terribly well thought out; instead, we should handle the case by
emitting the GRANT without the GRANTED BY clause. When the source
database is pre-v16, such cases are somewhat expected because those
versions didn't prevent dropping the grantor role; so don't even
print a warning that we did this. (This change therefore restores
pg_dumpall's pre-v16 behavior for these cases.) The case is not
expected in >= v16, so then we do print a warning, but soldiering on
with no GRANTED BY clause still seems like a reasonable strategy.
Per complaint from Robert Haas that we were now dropping GRANTs
altogether in easily-reachable scenarios.
Reported-by: Robert Haas <robertmhaas@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA+TgmoauoiW4ydDhdrseg+DD4Kwha=+TSZp18BrJeHKx3o1Fdw@mail.gmail.com
Backpatch-through: 16
Michael Paquier [Mon, 2 Mar 2026 02:10:38 +0000 (11:10 +0900)]
test_custom_types: Test module with fancy custom data types
This commit adds a new test module called "test_custom_types", that can
be used to stress code paths related to custom data type
implementations.
Currently, this is used as a test suite to validate the set of fixes
done in 3b7a6fa15720, that requires some typanalyze callbacks that can
force very specific backend behaviors, as of:
- typanalyze callback that returns "false" as status, to mark a failure
in computing statistics.
- typanalyze callback that returns "true" but let's the backend know
that no interesting stats could be computed, with stats_valid set to
"false".
This could be extended more in the future if more problems are found.
For simplicity, the module uses a fake int4 data type, that requires a
btree operator class to be usable with extended statistics. The type is
created by the extension, and its properties are altered in the test.
Like 3b7a6fa15720, this module is backpatched down to v14, for coverage
purposes.
Author: Michael Paquier <michael@paquier.xyz> Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/aaDrJsE1I5mrE-QF@paquier.xyz
Backpatch-through: 14
Michael Paquier [Mon, 2 Mar 2026 00:38:44 +0000 (09:38 +0900)]
Fix set of issues with extended statistics on expressions
This commit addresses two defects regarding extended statistics on
expressions:
- When building extended statistics in lookup_var_attr_stats(), the call
to examine_attribute() did not account for the possibility of a NULL
return value. This can happen depending on the behavior of a typanalyze
callback — for example, if the callback returns false, if no rows are
sampled, or if no statistics are computed. In such cases, the code
attempted to build MCV, dependency, and ndistinct statistics using a
NULL pointer, incorrectly assuming valid statistics were available,
which could lead to a server crash.
- When loading extended statistics for expressions,
statext_expressions_load() did not account for NULL entries in the
pg_statistic array storing expression statistics. Such NULL entries can
be generated when statistics collection fails for an expression, as may
occur during the final step of serialize_expr_stats(). An extended
statistics object defining N expressions requires N corresponding
elements in the pg_statistic array stored for the expressions, and some
of these elements can be NULL. This situation is reachable when a
typanalyze callback returns true, but sets stats_valid to indicate that
no useful statistics could be computed.
While these scenarios cannot occur with in-core typanalyze callbacks, as
far as I have analyzed, they can be triggered by custom data types with
custom typanalyze implementations, at least.
No tests are added in this commit. A follow-up commit will introduce a
test module that can be extended to cover similar edge cases if
additional issues are discovered. This takes care of the core of the
problem.
Attribute and relation statistics already offer similar protections:
- ANALYZE detects and skips the build of invalid statistics.
- Invalid catalog data is handled defensively when loading statistics.
This issue exists since the support for extended statistics on
expressions has been added, down to v14 as of a4d75c86bf15. Backpatch
to all supported stable branches.
Author: Michael Paquier <michael@paquier.xyz> Reviewed-by: Corey Huinker <corey.huinker@gmail.com> Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/aaDrJsE1I5mrE-QF@paquier.xyz
Backpatch-through: 14
Jeff Davis [Thu, 26 Feb 2026 20:25:00 +0000 (12:25 -0800)]
Fix more multibyte issues in ltree.
Commit 84d5efa7e3 missed some multibyte issues caused by short-circuit
logic in the callers. The callers assumed that if the predicate string
is longer than the label string, then it couldn't possibly be a match,
but it can be when using case-insensitive matching (LVAR_INCASE) if
casefolding changes the byte length.
Fix by refactoring to get rid of the short-circuit logic as well as
the function pointer, and consolidate the logic in a replacement
function ltree_label_match().
Tom Lane [Thu, 26 Feb 2026 17:26:52 +0000 (12:26 -0500)]
Fix Solution.pm for change in pg_config.h contents.
In commits 1d97e4788 et al, I forgot that pre-v17 branches
require updating Solution.pm when changing the set of
symbols generated in pg_config.h. Per buildfarm.
Tom Lane [Thu, 26 Feb 2026 17:06:58 +0000 (12:06 -0500)]
Use CXXFLAGS instead of CFLAGS for linking C++ code
Otherwise, this would break if using C and C++ compilers from
different families and they understand different options. It already
used the right flags for compiling, this is only for linking. Also,
the meson setup already did this correctly.
Back-patch of v18 commit 365b5a345 into older supported branches.
At the time we were only aware of trouble in v18, but as shown
by buildfarm member siren, older branches can hit the problem too.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/228700.1722717983@sss.pgh.pa.us
Discussion: https://postgr.es/m/3109540.1771698685@sss.pgh.pa.us
Backpatch-through: 14-17
Noah Misch [Thu, 26 Feb 2026 02:13:22 +0000 (18:13 -0800)]
EUC_CN, EUC_JP, EUC_KR, EUC_TW: Skip U+00A0 tests instead of failing.
Settings that ran the new test euc_kr.sql to completion would fail these
older src/pl tests. Use alternative expected outputs, for which psql
\gset and \if have reduced the maintenance burden. This fixes
"LANG=ko_KR.euckr LC_MESSAGES=C make check-world". (LC_MESSAGES=C fixes
IO::Pty usage in tests 010_tab_completion and 001_password.) That file
is new in commit c67bef3f3252a3a38bf347f9f119944176a796ce. Back-patch
to v14, like that commit.
Fujii Masao [Thu, 26 Feb 2026 00:02:53 +0000 (09:02 +0900)]
doc: Clarify INCLUDING COMMENTS behavior in CREATE TABLE LIKE.
The documentation for the INCLUDING COMMENTS option of the LIKE clause
in CREATE TABLE was inaccurate and incomplete. It stated that comments for
copied columns, constraints, and indexes are copied, but regarding comments
on constraints in reality only comments on CHECK and NOT NULL constraints
are copied; comments on other constraints (such as primary keys) are not.
In addition, comments on extended statistics are copied, but this was not
documented.
The CREATE FOREIGN TABLE documentation had a similar omission: comments
on extended statistics are also copied, but this was not mentioned.
This commit updates the documentation to clarify the actual behavior.
The CREATE TABLE reference now specifies that comments on copied columns,
CHECK constraints, NOT NULL constraints, indexes, and extended statistics are
copied. The CREATE FOREIGN TABLE reference now notes that comments on
extended statistics are copied as well.
Backpatch to all supported versions. Documentation updates related to
CREATE FOREIGN TABLE LIKE and NOT NULL constraint comment copying are
not applied to v17 and earlier, since those features were introduced in v18.
Fujii Masao [Wed, 25 Feb 2026 23:46:12 +0000 (08:46 +0900)]
Fix ProcWakeup() resetting wrong waitStart field.
Previously, when one process woke another that was waiting on a lock,
ProcWakeup() incorrectly cleared its own waitStart field (i.e.,
MyProc->waitStart) instead of that of the process being awakened.
As a result, the awakened process retained a stale lock-wait start timestamp.
This did not cause user-visible issues. pg_locks.waitstart was reported as
NULL for the awakened process (i.e., when pg_locks.granted is true),
regardless of the waitStart value.
Tom Lane [Wed, 25 Feb 2026 16:57:26 +0000 (11:57 -0500)]
Allow PG_PRINTF_ATTRIBUTE to be different in C and C++ code.
Although clang claims to be compatible with gcc's printf format
archetypes, this appears to be a falsehood: it likes __syslog__
(which gcc does not, on most platforms) and doesn't accept
gnu_printf. This means that if you try to use gcc with clang++
or clang with g++, you get compiler warnings when compiling
printf-like calls in our C++ code. This has been true for quite
awhile, but it's gotten more annoying with the recent appearance
of several buildfarm members that are configured like this.
To fix, run separate probes for the format archetype to use with the
C and C++ compilers, and conditionally define PG_PRINTF_ATTRIBUTE
depending on __cplusplus.
(We could alternatively insist that you not mix-and-match C and
C++ compilers; but if the case works otherwise, this is a poor
reason to insist on that.)
This commit back-patches 0909380e4 into supported branches.
Tom Lane [Wed, 25 Feb 2026 16:19:50 +0000 (11:19 -0500)]
Fix some cases of indirectly casting away const.
Newest versions of gcc+glibc are able to detect cases where code
implicitly casts away const by assigning the result of strchr() or
a similar function applied to a "const char *" value to a target
variable that's just "char *". This of course creates a hazard of
not getting a compiler warning about scribbling on a string one was
not supposed to, so fixing up such cases is good.
This patch fixes a dozen or so places where we were doing that.
Most are trivial additions of "const" to the target variable,
since no actually-hazardous change was occurring.
Thanks to Bertrand Drouvot for finding a couple more spots than
I had.
This commit back-patches relevant portions of 8f1791c61 and 9f7565c6c into supported branches. However, there are two
places in ecpg (in v18 only) where a proper fix is more
complicated than seems appropriate for a back-patch. I opted
to silence those two warnings by adding casts.
Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/1324889.1764886170@sss.pgh.pa.us
Discussion: https://postgr.es/m/3988414.1771950285@sss.pgh.pa.us
Backpatch-through: 14-18
Tom Lane [Wed, 25 Feb 2026 15:51:42 +0000 (10:51 -0500)]
Stabilize output of new isolation test insert-conflict-do-update-4.
The test added by commit 4b760a181 assumed that a table's physical
row order would be predictable after an UPDATE. But a non-heap table
AM might produce some other order. Even with heap AM, the assumption
seems risky; compare a3fd53bab for instance. Adding an ORDER BY is
cheap insurance and doesn't break any goal of the test.
Author: Pavel Borisov <pashkin.elfe@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CALT9ZEHcE6tpvumScYPO6pGk_ASjTjWojLkodHnk33dvRPHXVw@mail.gmail.com
Backpatch-through: 14
Jacob Champion [Tue, 24 Feb 2026 22:01:51 +0000 (14:01 -0800)]
pg_upgrade: Use max_protocol_version=3.0 for older servers
The grease patch in 4966bd3ed found its first problem: prior to the
February 2018 patch releases, no server knew how to negotiate protocol
versions, so pg_upgrade needs to take that into account when speaking to
those older servers.
This will be true even after the grease feature is reverted; we don't
need anyone to trip over this again in the future. Backpatch so that all
supported versions of pg_upgrade can gracefully handle an update to the
default protocol version. (This is needed for any distributions that
link older binaries against newer libpqs, such as Debian.) Branches
prior to 18 need an additional version check, for the existence of
max_protocol_version.
Per buildfarm member crake.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAOYmi%2B%3D4QhCjssfNEoZVK8LPtWxnfkwT5p-PAeoxtG9gpNjqOQ%40mail.gmail.com
Backpatch-through: 14
Richard Guo [Fri, 20 Feb 2026 09:04:26 +0000 (18:04 +0900)]
Fix computation of varnullingrels when translating appendrel Var
When adjust_appendrel_attrs translates a Var referencing a parent
relation into a Var referencing a child relation, it propagates
varnullingrels from the parent Var to the translated Var. Previously,
the code simply overwrote the translated Var's varnullingrels with
those of the parent.
This was incorrect because the translated Var might already possess
nonempty varnullingrels. This happens, for example, when a LATERAL
subquery within a UNION ALL references a Var from the nullable side of
an outer join. In such cases, the translated Var correctly carries
the outer join's relid in its varnullingrels. Overwriting these bits
with the parent Var's set caused the planner to lose track of the fact
that the Var could be nulled by that outer join.
In the reported case, because the underlying column had a NOT NULL
constraint, the planner incorrectly deduced that the Var could never
be NULL and discarded essential IS NOT NULL filters. This led to
incorrect query results where NULL rows were returned instead of being
filtered out.
To fix, use bms_add_members to merge the parent Var's varnullingrels
into the translated Var's existing set, preserving both sources of
nullability.
Back-patch to v16. Although the reported case does not seem to cause
problems in v16, leaving incorrect varnullingrels in the tree seems
like a trap for the unwary.
Bug: #19412 Reported-by: Sergey Shinderuk <s.shinderuk@postgrespro.ru>
Author: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19412-1d0318089b86859e@postgresql.org
Backpatch-through: 16
Thomas Munro [Tue, 17 Feb 2026 00:53:32 +0000 (13:53 +1300)]
Fix test_valid_server_encoding helper function.
Commit c67bef3f325 introduced this test helper function for use by
src/test/regress/sql/encoding.sql, but its logic was incorrect. It
confused an encoding ID for a boolean so it gave the wrong results for
some inputs, and also forgot the usual return macro. The mistake didn't
affect values actually used in the test, so there is no change in
behavior.
Also drop it and another missed function at the end of the test, for
consistency.
Noah Misch [Tue, 17 Feb 2026 02:04:58 +0000 (18:04 -0800)]
Suppress new "may be used uninitialized" warning.
Various buildfarm members, having compilers like gcc 8.5 and 6.3, fail
to deduce that text_substring() variable "E" is initialized if
slice_size!=-1. This suppression approach quiets gcc 8.5; I did not
reproduce the warning elsewhere. Back-patch to v14, like commit 9f4fd119b2cbb9a41ec0c19a8d6ec9b59b92c125.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1157953.1771266105@sss.pgh.pa.us
Backpatch-through: 14
Michael Paquier [Mon, 16 Feb 2026 23:41:34 +0000 (08:41 +0900)]
hstore: Fix NULL pointer dereference with receive function
The receive function of hstore was not able to handle correctly
duplicate key values when a new duplicate links to a NULL value, where a
pfree() could be attempted on a NULL pointer, crashing due to a pointer
dereference.
This problem would happen for a COPY BINARY, when stacking values like
that:
aa => 5
aa => null
The second key/value pair is discarded and pfree() calls are attempted
on its key and its value, leading to a pointer dereference for the value
part as the value is NULL. The first key/value pair takes priority when
a duplicate is found.
Don't reset 'latest_page_number' when replaying multixid truncation
'latest_page_number' is set to the correct value, according to
nextOffset, early at system startup. Contrary to the comment, it hence
should be set up correctly by the time we get to WAL replay.
This fixes a failure to replay WAL generated on older minor versions,
before commit 789d65364c (18.2, 17.8, 16.12, 15.16, 14.21). The
failure occurs after a truncation record has been replayed and looks
like this:
FATAL: could not access status of transaction 858112
DETAIL: Could not read from file "pg_multixact/offsets/000D" at offset 24576: read too few bytes.
CONTEXT: WAL redo at 3/2A3AB408 for MultiXact/CREATE_ID: 858111 offset 6695072 nmembers 5: 1048228 (sh) 1048271 (keysh) 1048316 (sh) 1048344 (keysh) 1048370 (sh)
Michael Paquier [Mon, 16 Feb 2026 03:18:31 +0000 (12:18 +0900)]
pgcrypto: Tweak error message for incorrect session key length
The error message added in 379695d3cc70 referred to the public key being
too long. This is confusing as it is in fact the session key included
in a PGP message which is too long. This is harmless, but let's be
precise about what is wrong.
Noah Misch [Sat, 14 Feb 2026 20:16:16 +0000 (12:16 -0800)]
Fix SUBSTRING() for toasted multibyte characters.
Commit 1e7fe06c10c0a8da9dd6261a6be8d405dc17c728 changed
pg_mbstrlen_with_len() to ereport(ERROR) if the input ends in an
incomplete character. Most callers want that. text_substring() does
not. It detoasts the most bytes it could possibly need to get the
requested number of characters. For example, to extract up to 2 chars
from UTF8, it needs to detoast 8 bytes. In a string of 3-byte UTF8
chars, 8 bytes spans 2 complete chars and 1 partial char.
Fix this by replacing this pg_mbstrlen_with_len() call with a string
traversal that differs by stopping upon finding as many chars as the
substring could need. This also makes SUBSTRING() stop raising an
encoding error if the incomplete char is past the end of the substring.
This is consistent with the general philosophy of the above commit,
which was to raise errors on a just-in-time basis. Before the above
commit, SUBSTRING() never raised an encoding error.
SUBSTRING() has long been detoasting enough for one more char than
needed, because it did not distinguish exclusive and inclusive end
position. For avoidance of doubt, stop detoasting extra.
Back-patch to v14, like the above commit. For applications using
SUBSTRING() on non-ASCII column values, consider applying this to your
copy of any of the February 12, 2026 releases.
Noah Misch [Sat, 14 Feb 2026 20:16:16 +0000 (12:16 -0800)]
pg_mblen_range, pg_mblen_with_len: Valgrind after encoding ereport.
The prior order caused spurious Valgrind errors. They're spurious
because the ereport(ERROR) non-local exit discards the pointer in
question. pg_mblen_cstr() ordered the checks correctly, but these other
two did not. Back-patch to v14, like commit 1e7fe06c10c0a8da9dd6261a6be8d405dc17c728.
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20260214053821.fa.noahmisch@microsoft.com
Backpatch-through: 14
Tom Lane [Wed, 11 Feb 2026 21:53:14 +0000 (16:53 -0500)]
Fix plpgsql's handling of "return simple_record_variable".
If the variable's value is null, exec_stmt_return() missed filling
in estate->rettype. This is a pretty old bug, but we'd managed not
to notice because that value isn't consulted for a null result ...
unless we have to cast it to a domain. That case led to a failure
with "cache lookup failed for type 0".
The correct way to assign the data type is known by exec_eval_datum.
While we could copy-and-paste that logic, it seems like a better
idea to just invoke exec_eval_datum, as the ROW case already does.
Reported-by: Pavel Stehule <pavel.stehule@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAFj8pRBT_ahexDf-zT-cyH8bMR_qcySKM8D5nv5MvTWPiatYGA@mail.gmail.com
Backpatch-through: 14
Fix pg_stat_get_backend_wait_event() for aux processes
The pg_stat_activity view shows information for aux processes, but the
pg_stat_get_backend_wait_event() and
pg_stat_get_backend_wait_event_type() functions did not. To fix, call
AuxiliaryPidGetProc(pid) if BackendPidGetProc(pid) returns NULL, like
we do in pg_stat_get_activity().
In version 17 and above, it's a little silly to use those functions
when we already have the ProcNumber at hand, but it was necessary
before v17 because the backend ID was different from ProcNumber. I
have other plans for wait_event_info on master, so it doesn't seem
worth applying a different fix on different versions now.
Reviewed-by: Sami Imseih <samimseih@gmail.com> Reviewed-by: Chao Li <li.evan.chao@gmail.com> Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://www.postgresql.org/message-id/c0320e04-6e85-4c49-80c5-27cfb3a58108@iki.fi
Backpatch-through: 14
Tom Lane [Wed, 11 Feb 2026 16:03:01 +0000 (11:03 -0500)]
Further stabilize a postgres_fdw test case.
The buildfarm occasionally shows a variant row order in the output
of this UPDATE ... RETURNING, implying that the preceding INSERT
dropped one of the rows into some free space within the table rather
than appending them all at the end. It's not entirely clear why that
happens some times and not other times, but we have established that
it's affected by concurrent activity in other databases of the
cluster. In any case, the behavior is not wrong; the test is at fault
for presuming that a seqscan will give deterministic row ordering.
Add an ORDER BY atop the update to stop the buildfarm noise.
The buildfarm seems to have shown this only in v18 and master
branches, but just in case the cause is older, back-patch to
all supported branches.
Dean Rasheed [Wed, 11 Feb 2026 10:53:00 +0000 (10:53 +0000)]
doc: Mention all SELECT privileges required by INSERT ... ON CONFLICT.
On the INSERT page, mention that SELECT privileges are also required
for any columns mentioned in the arbiter clause, including those
referred to by the constraint, and clarify that this applies to all
forms of ON CONFLICT, not just ON CONFLICT DO UPDATE.
Author: Dean Rasheed <dean.a.rasheed@gmail.com> Reviewed-by: Viktor Holmberg <v@viktorh.net>
Discussion: https://postgr.es/m/CAEZATCXGwMQ+x00YY9XYG46T0kCajH=21QaYL9Xatz0dLKii+g@mail.gmail.com
Backpatch-through: 14
Dean Rasheed [Wed, 11 Feb 2026 10:25:07 +0000 (10:25 +0000)]
doc: Clarify RLS policies applied for ON CONFLICT DO NOTHING.
On the CREATE POLICY page, the description of per-command policies
stated that SELECT policies are applied when an INSERT has an ON
CONFLICT DO NOTHING clause. However, that is only the case if it
includes an arbiter clause, so clarify that.
While at it, also clarify the comment in the regression tests that
cover this.
Author: Dean Rasheed <dean.a.rasheed@gmail.com> Reviewed-by: Viktor Holmberg <v@viktorh.net>
Discussion: https://postgr.es/m/CAEZATCXGwMQ+x00YY9XYG46T0kCajH=21QaYL9Xatz0dLKii+g@mail.gmail.com
Backpatch-through: 14
Tom Lane [Mon, 9 Feb 2026 15:14:22 +0000 (10:14 -0500)]
Harden _int_matchsel() against being attached to the wrong operator.
While the preceding commit prevented such attachments from occurring
in future, this one aims to prevent further abuse of any already-
created operator that exposes _int_matchsel to the wrong data types.
(No other contrib module has a vulnerable selectivity estimator.)
We need only check that the Const we've found in the query is indeed
of the type we expect (query_int), but there's a difficulty: as an
extension type, query_int doesn't have a fixed OID that we could
hard-code into the estimator.
Therefore, the bulk of this patch consists of infrastructure to let
an extension function securely look up the OID of a datatype
belonging to the same extension. (Extension authors have requested
such functionality before, so we anticipate that this code will
have additional non-security uses, and may soon be extended to allow
looking up other kinds of SQL objects.)
This is done by first finding the extension that owns the calling
function (there can be only one), and then thumbing through the
objects owned by that extension to find a type that has the desired
name. This is relatively expensive, especially for large extensions,
so a simple cache is put in front of these lookups.
Reported-by: Daniel Firer as part of zeroday.cloud
Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Noah Misch <noah@leadboat.com>
Security: CVE-2026-2004
Backpatch-through: 14
Tom Lane [Mon, 9 Feb 2026 15:07:31 +0000 (10:07 -0500)]
Require superuser to install a non-built-in selectivity estimator.
Selectivity estimators come in two flavors: those that make specific
assumptions about the data types they are working with, and those
that don't. Most of the built-in estimators are of the latter kind
and are meant to be safely attachable to any operator. If the
operator does not behave as the estimator expects, you might get a
poor estimate, but it won't crash.
However, estimators that do make datatype assumptions can malfunction
if they are attached to the wrong operator, since then the data they
get from pg_statistic may not be of the type they expect. This can
rise to the level of a security problem, even permitting arbitrary
code execution by a user who has the ability to create SQL objects.
To close this hole, establish a rule that built-in estimators are
required to protect themselves against being called on the wrong type
of data. It does not seem practical however to expect estimators in
extensions to reach a similar level of security, at least not in the
near term. Therefore, also establish a rule that superuser privilege
is required to attach a non-built-in estimator to an operator.
We expect that this restriction will have little negative impact on
extensions, since estimators generally have to be written in C and
thus superuser privilege is required to create them in the first
place.
This commit changes the privilege checks in CREATE/ALTER OPERATOR
to enforce the rule about superuser privilege, and fixes a couple
of built-in estimators that were making datatype assumptions without
sufficiently checking that they're valid.
Reported-by: Daniel Firer as part of zeroday.cloud
Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Noah Misch <noah@leadboat.com>
Security: CVE-2026-2004
Backpatch-through: 14
Tom Lane [Mon, 9 Feb 2026 15:02:23 +0000 (10:02 -0500)]
Add a syscache on pg_extension.oid.
An upcoming patch requires this cache so that it can track updates
in the pg_extension catalog. So far though, the EXTENSIONOID cache
only exists in v18 and up (see 490f869d9). We can add it in older
branches without an ABI break, if we are careful not to disturb the
numbering of existing syscache IDs.
In v16 and before, that just requires adding the new ID at the end
of the hand-assigned enum list, ignoring our convention about
alphabetizing the IDs. But in v17, genbki.pl enforces alphabetical
order of the IDs listed in MAKE_SYSCACHE macros. We can fake it
out by calling the new cache ZEXTENSIONOID.
Note that adding a syscache does change the required contents of the
relcache init file (pg_internal.init). But that isn't problematic
since we blow those away at postmaster start for other reasons.
Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Noah Misch <noah@leadboat.com>
Security: CVE-2026-2004
Backpatch-through: 14-17
Tom Lane [Mon, 9 Feb 2026 14:57:44 +0000 (09:57 -0500)]
Guard against unexpected dimensions of oidvector/int2vector.
These data types are represented like full-fledged arrays, but
functions that deal specifically with these types assume that the
array is 1-dimensional and contains no nulls. However, there are
cast pathways that allow general oid[] or int2[] arrays to be cast
to these types, allowing these expectations to be violated. This
can be exploited to cause server memory disclosure or SIGSEGV.
Fix by installing explicit checks in functions that accept these
types.
Reported-by: Altan Birler <altan.birler@tum.de>
Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Noah Misch <noah@leadboat.com>
Security: CVE-2026-2003
Backpatch-through: 14
Noah Misch [Mon, 9 Feb 2026 14:14:47 +0000 (06:14 -0800)]
Require PGP-decrypted text to pass encoding validation.
pgp_sym_decrypt() and pgp_pub_decrypt() will raise such errors, while
bytea variants will not. The existing "dat3" test decrypted to non-UTF8
text, so switch that query to bytea.
The long-term intent is for type "text" to always be valid in the
database encoding. pgcrypto has long been known as a source of
exceptions to that intent, but a report about exploiting invalid values
of type "text" brought this module to the forefront. This particular
exception is straightforward to fix, with reasonable effect on user
queries. Back-patch to v14 (all supported versions).
Reported-by: Paul Gerste (as part of zeroday.cloud) Reported-by: Moritz Sanft (as part of zeroday.cloud)
Author: shihao zhong <zhong950419@gmail.com> Reviewed-by: cary huang <hcary328@gmail.com>
Discussion: https://postgr.es/m/CAGRkXqRZyo0gLxPJqUsDqtWYBbgM14betsHiLRPj9mo2=z9VvA@mail.gmail.com
Backpatch-through: 14
Security: CVE-2026-2006
Thomas Munro [Sun, 11 Jan 2026 21:20:06 +0000 (10:20 +1300)]
Code coverage for most pg_mblen* calls.
A security patch changed them today, so close the coverage gap now.
Test that buffer overrun is avoided when pg_mblen*() requires more
than the number of bytes remaining.
This does not cover the calls in dict_thesaurus.c or in dict_synonym.c.
That code is straightforward. To change that code's input, one must
have access to modify installed OS files, so low-privilege users are not
a threat. Testing this would likewise require changing installed
share/postgresql/tsearch_data, which was enough of an obstacle to not
bother.
Security: CVE-2026-2006
Backpatch-through: 14 Co-authored-by: Thomas Munro <thomas.munro@gmail.com> Co-authored-by: Noah Misch <noah@leadboat.com> Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Thomas Munro [Wed, 7 Jan 2026 09:14:31 +0000 (22:14 +1300)]
Replace pg_mblen() with bounds-checked versions.
A corrupted string could cause code that iterates with pg_mblen() to
overrun its buffer. Fix, by converting all callers to one of the
following:
1. Callers with a null-terminated string now use pg_mblen_cstr(), which
raises an "illegal byte sequence" error if it finds a terminator in the
middle of the sequence.
2. Callers with a length or end pointer now use either
pg_mblen_with_len() or pg_mblen_range(), for the same effect, depending
on which of the two seems more convenient at each site.
3. A small number of cases pre-validate a string, and can use
pg_mblen_unbounded().
The traditional pg_mblen() function and COPYCHAR macro still exist for
backward compatibility, but are no longer used by core code and are
hereby deprecated. The same applies to the t_isXXX() functions.
Security: CVE-2026-2006
Backpatch-through: 14 Co-authored-by: Thomas Munro <thomas.munro@gmail.com> Co-authored-by: Noah Misch <noah@leadboat.com> Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi> Reported-by: Paul Gerste (as part of zeroday.cloud) Reported-by: Moritz Sanft (as part of zeroday.cloud)
Thomas Munro [Sun, 25 Jan 2026 22:22:32 +0000 (11:22 +1300)]
Fix mb2wchar functions on short input.
When converting multibyte to pg_wchar, the UTF-8 implementation would
silently ignore an incomplete final character, while the other
implementations would cast a single byte to pg_wchar, and then repeat
for the remaining byte sequence. While it didn't overrun the buffer, it
was surely garbage output.
Make all encodings behave like the UTF-8 implementation. A later change
for master only will convert this to an error, but we choose not to
back-patch that behavior change on the off-chance that someone is
relying on the existing UTF-8 behavior.
Security: CVE-2026-2006
Backpatch-through: 14
Author: Thomas Munro <thomas.munro@gmail.com> Reported-by: Noah Misch <noah@leadboat.com> Reviewed-by: Noah Misch <noah@leadboat.com> Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Thomas Munro [Wed, 4 Feb 2026 12:04:24 +0000 (01:04 +1300)]
Fix encoding length for EUC_CN.
While EUC_CN supports only 1- and 2-byte sequences (CS0, CS1), the
mb<->wchar conversion functions allow 3-byte sequences beginning SS2,
SS3.
Change pg_encoding_max_length() to return 3, not 2, to close a
hypothesized buffer overrun if a corrupted string is converted to wchar
and back again in a newly allocated buffer. We might reconsider that in
master (ie harmonizing in a different direction), but this change seems
better for the back-branches.
Also change pg_euccn_mblen() to report SS2 and SS3 characters as having
length 3 (following the example of EUC_KR). Even though such characters
would not pass verification, it's remotely possible that invalid bytes
could be used to compute a buffer size for use in wchar conversion.
Security: CVE-2026-2006
Backpatch-through: 14
Author: Thomas Munro <thomas.munro@gmail.com> Reviewed-by: Noah Misch <noah@leadboat.com> Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Michael Paquier [Sun, 8 Feb 2026 23:01:09 +0000 (08:01 +0900)]
pgcrypto: Fix buffer overflow in pgp_pub_decrypt_bytea()
pgp_pub_decrypt_bytea() was missing a safeguard for the session key
length read from the message data, that can be given in input of
pgp_pub_decrypt_bytea(). This can result in the possibility of a buffer
overflow for the session key data, when the length specified is longer
than PGP_MAX_KEY, which is the maximum size of the buffer where the
session data is copied to.
A script able to rebuild the message and key data that can trigger the
overflow is included in this commit, based on some contents provided by
the reporter, heavily editted by me. A SQL test is added, based on the
data generated by the script.
Reported-by: Team Xint Code as part of zeroday.cloud
Author: Michael Paquier <michael@paquier.xyz> Reviewed-by: Noah Misch <noah@leadboat.com>
Security: CVE-2026-2005
Backpatch-through: 14
Tom Lane [Sun, 8 Feb 2026 01:05:52 +0000 (20:05 -0500)]
meson: host_system value for Solaris is 'sunos' not 'solaris'.
This thinko caused us to not substitute our own getopt() code,
which results in failing to parse long options for the postmaster
since Solaris' getopt() doesn't do what we expect. This can be seen
in the results of buildfarm member icarus, which is the only one
trying to build via meson on Solaris.
Per consultation with pgsql-release, it seems okay to fix this
now even though we're in release freeze. The fix visibly won't
affect any other platforms, and it can't break Solaris/meson
builds any worse than they're already broken.
Thomas Munro [Fri, 6 Feb 2026 22:50:35 +0000 (11:50 +1300)]
Placate ABI checker.
It's not really an ABI break if you change the layout/size of an object
with incomplete type, as commit f94e9141 did, so advance the ABI
compliance reference commit in 16-18 to satisfy build farm animal crake.
Jacob Champion [Fri, 6 Feb 2026 19:08:59 +0000 (11:08 -0800)]
Protect against small overread in SASLprep validation
(This is a cherry-pick of 390b3cbbb, which I hadn't realized wasn't
backpatched. It was originally reported to security@ and determined not
to be a vulnerability; thanks to Stanislav Osipov for noticing the
omission in the back branches.)
In case of torn UTF8 in the input data we might end up going
past the end of the string since we don't account for length.
While validation won't be performed on a sequence with a NULL
byte it's better to avoid going past the end to beging with.
Fix by taking the length into consideration.
Reported-by: Stanislav Osipov <stasos24@gmail.com> Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAOYmi+mTnmM172g=_+Yvc47hzzeAsYPy2C4UBY3HK9p-AXNV0g@mail.gmail.com
Backpatch-through: 14
Michael Paquier [Fri, 6 Feb 2026 06:38:25 +0000 (15:38 +0900)]
Fix some error message inconsistencies
These errors are very unlikely going to show up, but in the event that
they happen, some incorrect information would have been provided:
- In pg_rewind, a stat() failure was reported as an open() failure.
- In pg_combinebackup, a check for the new directory of a tablespace
mapping was referred as the old directory.
- In pg_combinebackup, a failure in reading a source file when copying
blocks referred to the destination file.
The changes for pg_combinebackup affect v17 and newer versions. For
pg_rewind, all the stable branches are affected.
Author: Man Zeng <zengman@halodbtech.com>
Discussion: https://postgr.es/m/tencent_1EE1430B1E6C18A663B8990F@qq.com
Backpatch-through: 14
Provide a way to disable the use of posix_fallocate() for relation
files. It was introduced by commit 4d330a61bb1. The new setting
file_extend_method=write_zeros can be used as a workaround for problems
reported from the field:
* BTRFS compression is disabled by the use of posix_fallocate()
* XFS could produce spurious ENOSPC errors in some Linux kernel
versions, though that problem is reported to have been fixed
The default is file_extend_method=posix_fallocate if available, as
before. The write_zeros option is similar to PostgreSQL < 16, except
that now it's multi-block.
Fujii Masao [Wed, 4 Feb 2026 15:46:09 +0000 (00:46 +0900)]
Fix logical replication TAP test to read publisher log correctly.
Commit 5f13999aa11 added a TAP test for GUC settings passed via the
CONNECTION string in logical replication, but the buildfarm member
sungazer reported test failures.
The test incorrectly used the subscriber's log file position as the
starting offset when reading the publisher's log. As a result, the test
failed to find the expected log message in the publisher's log and
erroneously reported a failure.
This commit fixes the test to use the publisher's own log file position
when reading the publisher's log.
Also, to avoid similar confusion in the future, this commit splits the single
$log_location variable into $log_location_pub and $log_location_sub,
clearly distinguishing publisher and subscriber log positions.
Backpatched to v15, where commit 5f13999aa11 introduced the test.
Per buildfarm member sungazer.
This issue was reported and diagnosed by Alexander Lakhin.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/966ec3d8-1b6f-4f57-ae59-fc7d55bc9a5a@gmail.com
Backpatch-through: 15
John Naylor [Wed, 4 Feb 2026 10:55:49 +0000 (17:55 +0700)]
Fix various instances of undefined behavior
Mostly this involves checking for NULL pointer before doing operations
that add a non-zero offset.
The exception is an overflow warning in heap_fetch_toast_slice(). This
was caused by unneeded parentheses forcing an expression to be
evaluated to a negative integer, which then got cast to size_t.
Per clang 21 undefined behavior sanitizer.
Backpatch to all supported versions.
Co-authored-by: Alexander Lakhin <exclusion@gmail.com> Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/777bd201-6e3a-4da0-a922-4ea9de46a3ee@gmail.com
Backpatch-through: 14
Tom Lane [Fri, 30 Jan 2026 19:59:25 +0000 (14:59 -0500)]
Improve guards against false regex matches in BackgroundPsql.pm.
BackgroundPsql needs to wait for all the output from an interactive
psql command to come back. To make sure that's happened, it issues
the command, then issues \echo and \warn psql commands that echo
a "banner" string (which we assume won't appear in the command's
output), then waits for the banner strings to appear. The hazard
in this approach is that the banner will also appear in the echoed
psql commands themselves, so we need to distinguish those echoes from
the desired output. Commit 8b886a4e3 tried to do that by positing
that the desired output would be directly preceded and followed by
newlines, but it turns out that that assumption is timing-sensitive.
In particular, it tends to fail in builds made --without-readline,
wherein the command echoes will be made by the pty driver and may
be interspersed with prompts issued by psql proper.
It does seem safe to assume that the banner output we want will be
followed by a newline, since that should be the last output before
things quiesce. Therefore, we can improve matters by putting quotes
around the banner strings in the \echo and \warn psql commands, so
that their echoes cannot include banner directly followed by newline,
and then checking for just banner-and-newline in the match pattern.
While at it, spruce up the pump() call in sub query() to look like
the neater version in wait_connect(), and don't die on timeout
until after printing whatever we got.
Reported-by: Oleg Tselebrovskiy <o.tselebrovskiy@postgrespro.ru> Diagnosed-by: Oleg Tselebrovskiy <o.tselebrovskiy@postgrespro.ru>
Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Soumya S Murali <soumyamurali.work@gmail.com>
Discussion: https://postgr.es/m/db6fdb35a8665ad3c18be01181d44b31@postgrespro.ru
Backpatch-through: 14
Dean Rasheed [Fri, 30 Jan 2026 08:50:58 +0000 (08:50 +0000)]
Update .abi-compliance-history for change to TransitionCaptureState.
As noted in the commit message for b4307ae2e54, the change to the
TransitionCaptureState structure is nominally an ABI break, but it is
not expected to affect any third-party code. Therefore, add it to the
.abi-compliance-history file.
David Rowley [Mon, 26 Jan 2026 10:47:37 +0000 (23:47 +1300)]
Fix possible issue of a WindowFunc being in the wrong WindowClause
ed1a88dda made it so WindowClauses can be merged when all window
functions belonging to the WindowClause can equally well use some
other WindowClause without any behavioral changes. When that
optimization applies, the WindowFunc's "winref" gets adjusted to
reference the new WindowClause.
That commit does not work well with the deduplication logic in
find_window_functions(), which only added the WindowFunc to the list
when there wasn't already an identical WindowFunc in the list. That
deduplication logic meant that the duplicate WindowFunc wouldn't get the
"winref" changed when optimize_window_clauses() was able to swap the
WindowFunc to another WindowClause. This could lead to the following
error in the unlikely event that the deduplication code did something and
the duplicate WindowFunc happened to be moved into another WindowClause.
ERROR: WindowFunc with winref 2 assigned to WindowAgg with winref 1
As it turns out, the deduplication logic in find_window_functions() is
pretty bogus. It might have done something when added, as that code
predates b8d7f053c, which changed how projections work. As it turns
out, at least now we *will* evaluate the duplicate WindowFuncs. All
that the deduplication code seems to do today is assist in
underestimating the WindowAggPath costs due to not counting the
evaluation costs of duplicate WindowFuncs.
Ideally the fix would be to remove the deduplication code, but that
could result in changes to the plan costs, as duplicate WindowFuncs
would then be costed. Instead, let's play it safe and shift the
deduplication code so it runs after the other processing in
optimize_window_clauses().
Backpatch only as far as v16 as there doesn't seem to be any other harm
done by the WindowFunc deduplication code before then. This issue was
fixed in master by 7027dd499.
Dean Rasheed [Sat, 24 Jan 2026 11:30:50 +0000 (11:30 +0000)]
Fix trigger transition table capture for MERGE in CTE queries.
When executing a data-modifying CTE query containing MERGE and some
other DML operation on a table with statement-level AFTER triggers,
the transition tables passed to the triggers would fail to include the
rows affected by the MERGE.
The reason is that, when initializing a ModifyTable node for MERGE,
MakeTransitionCaptureState() would create a TransitionCaptureState
structure with a single "tcs_private" field pointing to an
AfterTriggersTableData structure with cmdType == CMD_MERGE. Tuples
captured there would then not be included in the sets of tuples
captured when executing INSERT/UPDATE/DELETE ModifyTable nodes in the
same query.
Since there are no MERGE triggers, we should only create
AfterTriggersTableData structures for INSERT/UPDATE/DELETE. Individual
MERGE actions should then use those, thereby sharing the same capture
tuplestores as any other DML commands executed in the same query.
This requires changing the TransitionCaptureState structure, replacing
"tcs_private" with 3 separate pointers to AfterTriggersTableData
structures, one for each of INSERT, UPDATE, and DELETE. Nominally,
this is an ABI break to a public structure in commands/trigger.h.
However, since this is a private field pointing to an opaque data
structure, the only way to create a valid TransitionCaptureState is by
calling MakeTransitionCaptureState(), and no extensions appear to be
doing that anyway, so it seems safe for back-patching.
Backpatch to v15, where MERGE was introduced.
Bug: #19380 Reported-by: Daniel Woelfel <dwwoelfel@gmail.com>
Author: Dean Rasheed <dean.a.rasheed@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19380-4e293be2b4007248%40postgresql.org
Backpatch-through: 15
Amit Langote [Fri, 23 Jan 2026 01:21:08 +0000 (10:21 +0900)]
Fix bogus ctid requirement for dummy-root partitioned targets
ExecInitModifyTable() unconditionally required a ctid junk column even
when the target was a partitioned table. This led to spurious "could
not find junk ctid column" errors when all children were excluded and
only the dummy root result relation remained.
A partitioned table only appears in the result relations list when all
leaf partitions have been pruned, leaving the dummy root as the sole
entry. Assert this invariant (nrels == 1) and skip the ctid requirement.
Also adjust ExecModifyTable() to tolerate invalid ri_RowIdAttNo for
partitioned tables, which is safe since no rows will be processed in
this case.
Bug: #19099 Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Amit Langote <amitlangote09@gmail.com> Reviewed-by: Tender Wang <tndrwang@gmail.com> Reviewed-by: Kirill Reshke <reshkekirill@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19099-e05dcfa022fe553d%40postgresql.org
Backpatch-through: 14
Tom Lane [Thu, 22 Jan 2026 23:35:31 +0000 (18:35 -0500)]
Remove faulty Assert in partitioned INSERT...ON CONFLICT DO UPDATE.
Commit f16241bef mistakenly supposed that INSERT...ON CONFLICT DO
UPDATE rejects partitioned target tables. (This may have been
accurate when the patch was written, but it was already obsolete
when committed.) Hence, there's an assertion that we can't see
ItemPointerIndicatesMovedPartitions() in that path, but the assertion
is triggerable.
Some other places throw error if they see a moved-across-partitions
tuple, but there seems no need for that here, because if we just retry
then we get the same behavior as in the update-within-partition case,
as demonstrated by the new isolation test. So fix by deleting the
faulty Assert. (The fact that this is the fix doubtless explains
why we've heard no field complaints: the behavior of a non-assert
build is fine.)
The TM_Deleted case contains a cargo-culted copy of the same Assert,
which I also deleted to avoid confusion, although I believe that one
is actually not triggerable.
Per our code coverage report, neither the TM_Updated nor the
TM_Deleted case were reached at all by existing tests, so this
patch adds tests for both.
Reported-by: Dmitry Koval <d.koval@postgrespro.ru>
Author: Joseph Koshakow <koshy44@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/f5fffe4b-11b2-4557-a864-3587ff9b4c36@postgrespro.ru
Backpatch-through: 14
Thomas Munro [Thu, 22 Jan 2026 02:43:13 +0000 (15:43 +1300)]
jit: Add missing inline pass for LLVM >= 17.
With LLVM >= 17, transform passes are provided as a string to
LLVMRunPasses. Only two strings were used: "default<O3>" and
"default<O0>,mem2reg".
With previous LLVM versions, an additional inline pass was added when
JIT inlining was enabled without optimization. With LLVM >= 17, the code
would go through llvm_inline, prepare the functions for inlining, but
the generated bitcode would be the same due to the missing inline pass.
This patch restores the previous behavior by adding an inline pass when
inlining is enabled but no optimization is done.
This fixes an oversight introduced by 76200e5e when support for LLVM 17
was added.
Backpatch-through: 14
Author: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com> Reviewed-by: Thomas Munro <thomas.munro@gmail.com> Reviewed-by: Andreas Karlsson <andreas@proxel.se> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de> Reviewed-by: Pierre Ducroquet <p.psql@pinaraf.info> Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com>
Discussion: https://postgr.es/m/CAO6_XqrNjJnbn15ctPv7o4yEAT9fWa-dK15RSyun6QNw9YDtKg%40mail.gmail.com
Álvaro Herrera [Wed, 21 Jan 2026 17:55:43 +0000 (18:55 +0100)]
amcheck: Fix snapshot usage in bt_index_parent_check
We were using SnapshotAny to do some index checks, but that's wrong and
causes spurious errors when used on indexes created by CREATE INDEX
CONCURRENTLY. Fix it to use an MVCC snapshot, and add a test for it.
Backpatch of 6bd469d26aca to branches 14-16. I previously misidentified
the bug's origin: it came in with commit 7f563c09f890 (pg11-era, not 5ae2087202af as claimed previously), so all live branches are affected.
Also take the opportunity to fix some comments that we failed to update
in the original commits and apply pgperltidy. In branch 14, remove the
unnecessary test plan specification (which would have need to have been
changed anyway; c.f. commit 549ec201d613.)
Diagnosed-by: Donghang Lin <donghanglin@gmail.com>
Author: Mihail Nikalayeu <mihailnikalayeu@gmail.com> Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Backpatch-through: 17
Discussion: https://postgr.es/m/CANtu0ojmVd27fEhfpST7RG2KZvwkX=dMyKUqg0KM87FkOSdz8Q@mail.gmail.com
Tom Lane [Sun, 18 Jan 2026 19:54:33 +0000 (14:54 -0500)]
Update time zone data files to tzdata release 2025c.
This is pretty pro-forma for our purposes, as the only change
is a historical correction for pre-1976 DST laws in
Baja California. (Upstream made this release mostly to update
their leap-second data, which we don't use.) But with minor
releases coming up, we should be up-to-date.
Michael Paquier [Sun, 18 Jan 2026 08:25:01 +0000 (17:25 +0900)]
Fix error message related to end TLI in backup manifest
The code adding the WAL information included in a backup manifest is
cross-checked with the contents of the timeline history file of the end
timeline. A check based on the end timeline, when it fails, reported
the value of the start timeline in the error message. This error is
fixed to show the correct timeline number in the report.
This error report would be confusing for users if seen, because it would
provide an incorrect information, so backpatch all the way down.
Amit Langote [Fri, 16 Jan 2026 04:01:52 +0000 (13:01 +0900)]
Fix segfault from releasing locks in detached DSM segments
If a FATAL error occurs while holding a lock in a DSM segment (such
as a dshash lock) and the process is not in a transaction, a
segmentation fault can occur during process exit.
The problem sequence is:
1. Process acquires a lock in a DSM segment (e.g., via dshash)
2. FATAL error occurs outside transaction context
3. proc_exit() begins, calling before_shmem_exit callbacks
4. dsm_backend_shutdown() detaches all DSM segments
5. Later, on_shmem_exit callbacks run
6. ProcKill() calls LWLockReleaseAll()
7. Segfault: the lock being released is in unmapped memory
This only manifests outside transaction contexts because
AbortTransaction() calls LWLockReleaseAll() during transaction
abort, releasing locks before DSM cleanup. Background workers and
other non-transactional code paths are vulnerable.
Fix by calling LWLockReleaseAll() unconditionally at the start of
shmem_exit(), before any callbacks run. Releasing locks before
callbacks prevents the segfault - locks must be released before
dsm_backend_shutdown() detaches their memory. This is safe because
after an error, held locks are protecting potentially inconsistent
data anyway, and callbacks can acquire fresh locks if needed.
Also add a comment noting that LWLockReleaseAll() must be safe to
call before LWLock initialization (which it is, since
num_held_lwlocks will be 0), plus an Assert for the post-condition.
This fix aligns with the original design intent from commit 001a573a2, which noted that backends must clean up shared memory
state (including releasing lwlocks) before unmapping dynamic shared
memory segments.
Fix 'unexpected data beyond EOF' on replica restart
On restart, a replica can fail with an error like 'unexpected data
beyond EOF in block 200 of relation T/D/R'. These are the steps to
reproduce it:
- A relation has a size of 400 blocks.
- Blocks 201 to 400 are empty.
- Block 200 has two rows.
- Blocks 100 to 199 are empty.
- A restartpoint is done
- Vacuum truncates the relation to 200 blocks
- A FPW deletes a row in block 200
- A checkpoint is done
- A FPW deletes the last row in block 200
- Vacuum truncates the relation to 100 blocks
- The replica restarts
When the replica restarts:
- The relation on disk starts at 100 blocks, because all the
truncations were applied before restart.
- The first truncate to 200 blocks is replayed. It silently fails, but
it will still (incorrectly!) update the cache size to 200 blocks
- The first FPW on block 200 is applied. XLogReadBufferForRead relies
on the cached size and incorrectly assumes that the page already
exists in the file, and thus won't extend the relation.
- The online checkpoint record is replayed, calling smgrdestroyall
which causes the cached size to be discarded
- The second FPW on block 200 is applied. This time, the detected size
is 100 blocks, an extend is attempted. However, the block 200 is
already present in the buffer cache due to the first FPW. This
triggers the 'unexpected data beyond EOF'.
To fix, update the cached size in SmgrRelation with the current size
rather than the requested new size, when the requested new size is
greater.
Add check for invalid offset at multixid truncation
If a multixid with zero offset is left behind after a crash, and that
multixid later becomes the oldest multixid, truncation might try to
look up its offset and read the zero value. In the worst case, we
might incorrectly use the zero offset to truncate valid SLRU segments
that are still needed. I'm not sure if that can happen in practice, or
if there are some other lower-level safeguards or incidental reasons
that prevent the caller from passing an unwritten multixid as the
oldest multi. But better safe than sorry, so let's add an explicit
check for it.
In stable branches, we should perhaps do the same check for
'oldestOffset', i.e. the offset of the old oldest multixid (in master,
'oldestOffset' is gone). But if the old oldest multixid has an invalid
offset, the damage has been done already, and we would never advance
past that point. It's not clear what we should do in that case. The
check that this commit adds will prevent such an multixid with invalid
offset from becoming the oldest multixid in the first place, which
seems enough for now.
Michael Paquier [Wed, 14 Jan 2026 07:02:39 +0000 (16:02 +0900)]
pg_waldump: Relax LSN comparison check in TAP test
The test 002_save_fullpage.pl, checking --save-fullpage fails with
wal_consistency_checking enabled, due to the fact that the block saved
in the file has the same LSN as the LSN used in the file name. The test
required that the block LSN is stritly lower than file LSN. This commit
relaxes the check a bit, by allowing the LSNs to match.
While on it, the test name is reworded to include some information about
the file and block LSNs, which is useful for debugging.
Fujii Masao [Tue, 13 Jan 2026 13:54:45 +0000 (22:54 +0900)]
doc: Document DEFAULT option in file_fdw.
Commit 9f8377f7a introduced the DEFAULT option for file_fdw but did not
update the documentation. This commit adds the missing description of
the DEFAULT option to the file_fdw documentation.
Backpatch to v16, where the DEFAULT option was introduced.
Jacob Champion [Fri, 9 Jan 2026 18:02:43 +0000 (10:02 -0800)]
doc: Improve description of publish_via_partition_root
Reword publish_via_partition_root's opening paragraph. Describe its
behavior more clearly, and directly state that its default is false.
Per complaint by Peter Smith; final text of the patch made in
collaboration with Chao Li.
Author: Chao Li <li.evan.chao@gmail.com>
Author: Peter Smith <peter.b.smith@fujitsu.com> Reported-by: Peter Smith <peter.b.smith@fujitsu.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/CAHut%2BPu7SpK%2BctOYoqYR3V4w5LKc9sCs6c_qotk9uTQJQ4zp6g%40mail.gmail.com
Backpatch-through: 14
David Rowley [Thu, 8 Jan 2026 22:03:48 +0000 (11:03 +1300)]
Fix possible incorrect column reference in ERROR message
When creating a partition for a RANGE partitioned table, the reporting
of errors relating to converting the specified range values into
constant values for the partition key's type could display the name of a
previous partition key column when an earlier range was specified as
MINVALUE or MAXVALUE.
This was caused by the code not correctly incrementing the index that
tracks which partition key the foreach loop was working on after
processing MINVALUE/MAXVALUE ranges.
Fix by using foreach_current_index() to ensure the index variable is
always set to the List element being worked on.
Amit Kapila [Thu, 8 Jan 2026 07:07:23 +0000 (07:07 +0000)]
Prevent invalidation of newly created replication slots.
A race condition could cause a newly created replication slot to become
invalidated between WAL reservation and a checkpoint.
Previously, if the required WAL was removed, we retried the reservation
process. However, the slot could still be invalidated before the retry if
the WAL was not yet removed but the checkpoint advanced the redo pointer
beyond the slot's intended restart LSN and computed the minimum LSN that
needs to be preserved for the slots.
The fix is to acquire an exclusive lock on ReplicationSlotAllocationLock
during WAL reservation, and a shared lock during the minimum LSN
calculation at checkpoints to serialize the process. This ensures that, if
WAL reservation occurs first, the checkpoint waits until restart_lsn is
updated before calculating the minimum LSN. If the checkpoint runs first,
subsequent WAL reservations pick a position at or after the latest
checkpoint's redo pointer.
We used a similar fix in HEAD (via commit 006dd4b2e5) and 18. The
difference is that in 17 and prior branches we need to additionally handle
the race condition with slot's minimum LSN computation during checkpoints.
John Naylor [Wed, 7 Jan 2026 09:02:19 +0000 (16:02 +0700)]
createuser: Update docs to reflect defaults
Commit c7eab0e97 changed the default password_encryption setting to
'scram-sha-256', so update the example for creating a user with an
assigned password.
In addition, commit 08951a7c9 added new options that in turn pass
default tokens NOBYPASSRLS and NOREPLICATION to the CREATE ROLE
command, so fix this omission as well for v16 and later.
Reported-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/cff1ea60-c67d-4320-9e33-094637c2c4fb%40iki.fi
Backpatch-through: 14
David Rowley [Tue, 6 Jan 2026 04:30:32 +0000 (17:30 +1300)]
Fix issue with EVENT TRIGGERS and ALTER PUBLICATION
When processing the "publish" options of an ALTER PUBLICATION command,
we call SplitIdentifierString() to split the options into a List of
strings. Since SplitIdentifierString() modifies the delimiter
character and puts NULs in their place, this would overwrite the memory
of the AlterPublicationStmt. Later in AlterPublicationOptions(), the
modified AlterPublicationStmt is copied for event triggers, which would
result in the event trigger only seeing the first "publish" option
rather than all options that were specified in the command.
To fix this, make a copy of the string before passing to
SplitIdentifierString().
Here we also adjust a similar case in the pgoutput plugin. There's no
known issues caused by SplitIdentifierString() here, so this is being
done out of paranoia.
Thanks to Henson Choi for putting together an example case showing the
ALTER PUBLICATION issue.
Fujii Masao [Tue, 6 Jan 2026 02:57:12 +0000 (11:57 +0900)]
Add TAP test for GUC settings passed via CONNECTION in logical replication.
Commit d926462d819 restored the behavior of passing GUC settings from
the CONNECTION string to the publisher's walsender, allowing per-connection
configuration.
This commit adds a TAP test to verify that behavior works correctly.
Since commit d926462d819 was recently applied and backpatched to v15,
this follow-up commit is also backpatched accordingly.
Author: Fujii Masao <masao.fujii@gmail.com> Reviewed-by: Chao Li <lic@highgo.com> Reviewed-by: Kirill Reshke <reshkekirill@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Japin Li <japinli@hotmail.com>
Discussion: https://postgr.es/m/CAHGQGwGYV+-abbKwdrM2UHUe-JYOFWmsrs6=QicyJO-j+-Widw@mail.gmail.com
Backpatch-through: 15
Fujii Masao [Tue, 6 Jan 2026 02:54:46 +0000 (11:54 +0900)]
Honor GUC settings specified in CREATE SUBSCRIPTION CONNECTION.
Prior to v15, GUC settings supplied in the CONNECTION clause of
CREATE SUBSCRIPTION were correctly passed through to
the publisher's walsender. For example:
would cause wal_sender_timeout to take effect on the publisher's walsender.
However, commit f3d4019da5d changed the way logical replication
connections are established, forcing the publisher's relevant
GUC settings (datestyle, intervalstyle, extra_float_digits) to
override those provided in the CONNECTION string. As a result,
from v15 through v18, GUC settings in the CONNECTION string were
always ignored.
This regression prevented per-connection tuning of logical replication.
For example, using a shorter timeout for walsender connecting
to a nearby subscriber and a longer one for walsender connecting
to a remote subscriber.
This commit restores the intended behavior by ensuring that
GUC settings in the CONNECTION string are again passed through
and applied by the walsender, allowing per-connection configuration.
Backpatch to v15, where the regression was introduced.
Author: Fujii Masao <masao.fujii@gmail.com> Reviewed-by: Chao Li <lic@highgo.com> Reviewed-by: Kirill Reshke <reshkekirill@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Japin Li <japinli@hotmail.com>
Discussion: https://postgr.es/m/CAHGQGwGYV+-abbKwdrM2UHUe-JYOFWmsrs6=QicyJO-j+-Widw@mail.gmail.com
Backpatch-through: 15
projects / thirdparty / postgresql.git / log
