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Commit Graph

60209 Commits

Author SHA1 Message Date
Jacob Champion
4fcccea972 Move SplitGUCList() to fe_utils
This is needed so that all versions of pg_upgrade that migrate logical
replication slots can parse the new output_plugin_libraries GUC.

Backpatch-through: 17
Security: CVE-2026-6471
2026-08-10 06:38:18 -07:00
Noah Misch
e41c72aff0 Empty search_path in amcheck.
A grantee of amcheck function EXECUTE privilege could execute arbitrary
functions as the owners of expression indexes that depend on the search
path.  An expression like (lower(col)) was not vulnerable, because
lower() is resolved at CREATE INDEX time.  However, an expression
calling an sql-language or plpgsql-language function often was
vulnerable, even if it used search_path only to find objects in
pg_catalog.  The amcheck documentation has been warning about data
disclosure after such a GRANT, not about function execution.

This might cause new amcheck errors when index expressions rely on a
broader search_path.  Such indexes have seen errors during auto-analyze
since CVE-2018-1058 commit 582edc369c, and
v17 amcheck always worked this way.  Hence, the risk is low.

Leave a comment on the one other sandbox entrance that doesn't empty
search_path.  In its case, the choice was valid.

Back-patch to v14 (all supported versions), but v17 was safe already.
Commit 2af07e2f74 (v17) unintentionally
blocked the attack, and commit d70b17636d
(v18) unintentionally removed that protection.  Hence, this adds to v17
just a test and a comment.  While emptying search_path became more
widespread in commit 2af07e2f74 (v17),
none of its other changes blocked an attack available in v16, even when
considering GRANT.  For example, brin_summarize_range() has had an owner
check that GRANT does not override.

Reported-by: 王跃林 <violin0613@tju.edu.cn>
Reported-by: Jacob Brazeal <jacob.brazeal@gmail.com>
Backpatch-through: 14
Security: CVE-2026-14673
2026-08-10 06:38:18 -07:00
Nathan Bossart
dec60e8ada Use value of scram_iterations in mock_scram_secret().
Presently, mock_scram_secret() always uses
SCRAM_SHA_256_DEFAULT_ITERATIONS, which poses an observable
response discrepancy hazard when scram_iterations is set to
something else.  To fix, use the value of the configuration
parameter instead, and document that unauthenticated users can
discover the existence of roles with passwords created with
different iteration counts.

Reported-by: Radim Marek <radim@boringsql.com>
Author: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Jacob Champion <champion.p@gmail.com>
Security: CVE-2026-14672
Backpatch-through: 16
2026-08-10 06:38:18 -07:00
Nathan Bossart
5981fe370a Obstruct EXTRACT() field name deparse injection.
The parser accepts any string as an EXTRACT() field name, but
deparsing does not quote and escape it accordingly.  To fix, quote
and escape the field name during deparsing as needed.  It might be
a good idea to validate the field name during parsing and
deparsing, too, but that is left as a future exercise.

Reported-by: Ben Morris in collaboration with Claude and Anthropic Research
Author: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Etsuro Fujita <etsuro.fujita@gmail.com>
Security: CVE-2026-15741
Backpatch-through: 14
2026-08-10 06:38:18 -07:00
Michael Paquier
067a64d40f Reject GSSEncRequest after direct SSL connection
When a direct SSL connection was established, ProcessStartupPacket()
still accepted GSSEncRequest messages.  The GSSAPI negotiation would
then use raw writes and reads, bypassing the TLS encryption layer.
After the GSS encryption was established, the connection continued to
use TLS.  This could betray the HBA rules so as the backend does
protocol exchanges inconsistent with the connection policies in place,
with TLS taking priority over GSS in the backend.

The SSL negotiation path already guarded against attempts to request
SSL after a direct SSL request has been processed.  The GSS path is now
guarded the same way when receiving a startup packet.

Reported-by: p4p3r <kbfanta@naver.com>
Author: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Jacob Champion <champion.p@gmail.com>
Backpatch-through: 17
Security: CVE-2026-14681
2026-08-10 06:38:18 -07:00
Michael Paquier
c3c830272a ecpg: Fix out-of-bound writes due to processing of invalid bytea data
ECPG assumes that any bytea data it receives from a backend starts with
'\x' as its first two bytes, but a check was missed to enforce that.  A
rogue server sending some garbage bytea data would be able to crash a
client, resulting in a client-side DoS, in the most common cases.

Reported-by: ylwangtju <ylwangtju@qq.com>
Backpatch-through: 14
Security: CVE-2026-16241
2026-08-10 06:38:18 -07:00
Heikki Linnakangas
b56cc7deb9 Use palloc_array() in pltcl and plperl to avoid overflow
Some of these could overflow on 32-bit systems with the right input.
Convert all cases where we called palloc() with multiplication to fix
them. Not all of them were bugs, but it's better to be safe than
sorry.

Reported-by: Tulya Project, Team Dhiutsa, Bitecope Technologies Private Ltd
Backpatch-through: 14
Security: CVE-2026-14677
2026-08-10 06:38:18 -07:00
Heikki Linnakangas
1af08af694 Fix pg_trgm's picksplit function with all-true datums
The CACHESIGN.sign field is a BITVECP, not a TRGM, so you should not
use GETSIGN() on it. You don't get a compiler warning because the
GETSIGN() macro includes a cast. It resulted in a bogus read beyond
end of buffer, which would cause bad split decisions or a crash if
you're very unlucky.

Reported-by: Mehmet D. INCE <mehmet@mehmetince.net>
Backpatch-through: 14
Security: CVE-2026-14678
2026-08-10 06:38:18 -07:00
Masahiko Sawada
75a03c569c Preserve the owner of extended statistics rebuilt by ALTER TABLE.
When ALTER TABLE ... ALTER COLUMN TYPE (or any subcommand that rebuilds
them) drops and re-creates the extended statistics objects depending on
the altered column, the re-created objects were owned by the role running
ALTER TABLE rather than by the original owner of the statistics.

Remember each object's owner before dropping it, and restore it on
re-creation.

CreateStatistics()'s signature changes and CreateStatsStmt gains a field,
but no known third-party code calls the former or constructs the latter.

Author: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Noah Misch <noah@leadboat.com>
Backpatch-through: 14
Security: CVE-2026-6469
2026-08-10 06:38:18 -07:00
Tom Lane
83d0a083f1 Return nulls honestly in aggregate "combine" functions.
numeric_combine() and several other state-combining functions for
aggregates cheated for the case of both inputs being NULL: they
returned a null pointer without bothering to mark it as a SQL NULL.
This was harmless in the expected usage where the result would be
passed to the same combine function or a related aggregate final
function.  But it's bad news from a security standpoint, because
now that value can be passed to an internal-accepting function
even if said function is strict.  While a previous patch prevented
such queries from being issued, it seems like good defense-in-depth
to expend the few additional lines of code needed to do this properly.
Comparable functions such as array_agg_combine() already do so.

Reported-by: Amy Burnett (OpenAI Codex Security)
Author: Tom Lane <tgl@sss.pgh.pa.us>
Backpatch-through: 14
Security: CVE-2026-14680
2026-08-10 06:38:18 -07:00
Tom Lane
eb9e552974 Reject calls from SQL to functions that take or return type internal.
Allowing that is a security hole, since there are many different
functions with different ideas of what their "internal" argument or
result is.  We already had a defense against the easy case of
"'foo'::internal", but that turns out to be insufficient.  Lock down
both function and operator syntax.  Also disallow attempts to cast to
or from type internal; those would mostly fail anyway, but we have
created some holes with features such as CoerceViaIO.

Reported-by: Amy Burnett (OpenAI Codex Security)
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Backpatch-through: 14
Security: CVE-2026-14680
2026-08-10 06:38:17 -07:00
Tom Lane
8a40f4b092 Protect some fixed-size arrays that have FUNC_MAX_ARGS elements.
The maximum number of arguments allowed for an aggregate function
is FUNC_MAX_ARGS-1 (since the underlying transfn and/or finalfn
will be called with one more argument).  parse_func.c failed to
enforce this, allowing construction of calls that would try to
pass FUNC_MAX_ARGS+1 to the underlying functions, resulting in
a memory stomp in the executor.  Add correct checking there.

Since it's possible that a bad call has been stored in a view or
SQL function, also add checks in various aggregate-related and
window-function-related code that there are not more than
FUNC_MAX_ARGS arguments.  These will also protect us against the
possibility that we're trying to run a stored view that was made
by a server executable with different FUNC_MAX_ARGS.  (Arguably,
that scenario does not qualify as a security problem.  But let's
just tighten up all of this while we're here, rather than split
hairs over whether an overrun is reachable.)

Likewise check in compute_function_hashkey.  Here the hazard is
directly from a pg_proc row, but the scenario is the same.

PL/Tcl has a similar issue with a fixed-size string buffer.
Let's just replace that buffer with a Tcl_DString, removing the
whole issue and making the code look more like what's around it.

There are a lot of other FUNC_MAX_ARGS-sized arrays, but the rest
have nearby guards already, some with comments explicitly pointing
out the hazard of FUNC_MAX_ARGS changing.

I also used palloc_array() in a few related places in funcapi.c.
Those aren't live hazards AFAICS, but nearby code has been
palloc_array-ified already, so it seemed inconsistent to not use
it here.

Reported-by: Masahiko Sawada <sawada.mshk@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Backpatch-through: 14
Security: CVE-2026-14679
2026-08-10 06:38:17 -07:00
Tom Lane
c2b16f5d49 pg_dump: avoid assuming how long pg_proc.protrftypes can be.
The backend doesn't impose any particular limit on the length of this
array, and since there could be entries for both input and output
arguments, it's feasible for the length to exceed FUNC_MAX_ARGS
even without funny business.  This could lead to crashes or worse.

Moreover, pg_dump shouldn't rely on hard-coding FUNC_MAX_ARGS in the
first place: it has no business assuming that the backend it's dumping
from was compiled with the same value of FUNC_MAX_ARGS that it is.
So the stanza in dumpFunc() that allocates exactly FUNC_MAX_ARGS space
for the parsed OID array is fundamentally misguided.  And it's broken
in another way too: if there are exactly FUNC_MAX_ARGS OIDs, then
parseOidArray won't zero-fill any entries, allowing the subsequent
loop to run off the end of the array.  A crash seems unlikely in
this variant, but garbage output is certain.

To fix, redesign parseOidArray's API so that it does the
array-mallocing, which simplifies the callers anyway.  While we're
here, tighten and modernize it a bit; in particular, split it into
separate functions for OIDs and integers, as was foreseen long ago.
This lets us get rid of the confusing type-punning involved in
having IndxInfo.indkeys be declared as "Oid *" when it's really
potentially-signed ints.  Also, most of the callers expect an exact
number of array entries, so make it verify that not just check for
"too many".

I noted while testing that this dumpFunc() stanza isn't even reached
during check-world.  Add a function with transform to the regression
tests to rectify that.

Reported-by: Masahiko Sawada <sawada.mshk@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Backpatch-through: 14
Security: CVE-2026-19385
2026-08-10 06:38:17 -07:00
Tom Lane
797e3cc4c4 Replace fixed-size, too-short array with a palloc'd one.
MatchNamedCall's arggiven array was declared FUNC_MAX_ARGS long,
but we may actually use up to pronallargs elements, and that can
be more than FUNC_MAX_ARGS if the function has OUT arguments
(cf. ProcedureCreate).  Convert it to a palloc'd array.

Reported-by: Zheng Yu <zheng@depthfirst.com>
Reported-by: ylwangtju <ylwangtju@qq.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Backpatch-through: 14
Security: CVE-2026-14679
2026-08-10 06:38:17 -07:00
Tom Lane
0ebf896f44 Be more wary about constant's datatype in scalarineqsel().
The special case here for estimating conditions involving a ctid
column failed to check that the RHS constant is of type tid.
While that'd always be true for the built-in operators that
reference this selectivity estimator, a maliciously constructed
operator could provide a user-controlled Datum value that would
get interpreted as an ItemPointer pointer.  That at least risks
SIGSEGV, and perhaps with a bit of sweat it could be used for
server memory disclosure.

Reported-by: Hcamael <baiyjrh@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Noah Misch <noah@leadboat.com>
Backpatch-through: 14
Security: CVE-2026-14668
2026-08-10 06:38:17 -07:00
Tom Lane
2d78c34f82 Harden PL/Perl code against "tied" Perl arrays and hashes.
Tied arrays might report different sizes each time they are inspected.
To avoid generating a corrupt result array, fix plperl_array_to_datum()
to read av_len() of each input array only once.  If the input does
appear to get shorter, we'll fill nulls for the now-missing entries,
which seems fine.  Conversely, if it gets longer, we'll ignore the new
entries.

plperl_to_hstore() assumed that Perl's hv_iterinit() returns the
number of entries in the given Perl hash.  Usually that's true,
but per the Perl docs, "the return value is currently only meaningful
for hashes without tie magic".  That could potentially end in a memory
stomp.  We don't depend on that result value anywhere else, so don't
do so here either.

Reported-by: Hcamael <baiyjrh@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Backpatch-through: 14
Security: CVE-2026-14670
2026-08-10 06:38:17 -07:00
Masahiko Sawada
e91dcfccaa Fix potential buffer overrun in regexp match/split functions.
setup_regexp_matches() sizes the buffer used to convert matched
substrings back from pg_wchar form at the smaller of maxlen*eml and
the original string's byte length, on the assumption that such a
conversion cannot produce more bytes than the string it came
from. That assumption holds only for validly encoded input. But
pg_mb2wchar_with_len() silently accepts bytes that are invalid in the
database encoding, turning each such byte into one pg_wchar, and
converting that back can take more bytes than the input did. A string
made of such bytes therefore overruns the conversion buffer by up to
its own length, corrupting the following memory. regexp_match(),
regexp_matches(), regexp_split_to_table() and regexp_split_to_array()
are all affected.

Fix by dropping the tighter bound and always allocating maxlen*eml + 1
bytes.

Reported-by: Francesco Verardi <frevadiscor89@gmail.com>
Author: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Backpatch-through: 14
Security: CVE-2026-14664
2026-08-10 06:38:17 -07:00
Tom Lane
8e87bd4731 Harden tsquery code against overflows.
The only overflow hazards I could find in tsquery construction
are in QTN2QT(), which builds a flat tsquery datum from the
QTNode tree representation used by tsquery_or, tsquery_rewrite,
and allied functions.  There are two:

1. It seems theoretically possible for the outputs of cntsize() to
overflow an int, so I widened them to size_t.  There's no hazard
certainly in tsquery_or and friends, but tsquery_rewrite could expand
the query tree by large multiples (by replacing many identical
subtrees with a large replacement tree), so in a 64-bit machine
with plenty of available memory it should be possible to build a
QTNode tree large enough to cause that.  If these counters did
overflow then we'd under-allocate the output tsquery and have a heap
overwrite problem.  size_t is sufficient, since it's counting the size
of a subset of an in-memory data structure.  We also have to fix the
TSQUERY_TOO_BIG() macro to not get confused if sumlen exceeds
MaxAllocSize.

2. fillQT() neglects to check that the new "distance" value for a
QI_VAL item fits into the available 20-bit field.  It's quite easy
to reach this, for example by tsquery_or'ing two near-megabyte-sized
tsquerys.  However, the result is only a corrupt tsquery that does
not represent the expected query, so perhaps this doesn't rise to
the level of a security bug.  Nonetheless it should be fixed.

Note: I followed the practice used in other tsquery code of checking
each distance value as it's assigned, which means that the last
operand string could extend past the MAXSTRPOS boundary.  This is a
bit different from the pattern used for tsvectors, which insist that
the total data length not exceed MAXSTRPOS and thereby avoid making
per-item checks.  Perhaps that should be harmonized sometime, but for
now it's okay for the two types to do this differently as long as
each one is self-consistent.

Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Backpatch-through: 14
Security: CVE-2026-14662
2026-08-10 06:38:17 -07:00
Tom Lane
fe0b5bd6de Harden tsvector code against overflows.
The core of this patch is to prevent array_to_tsvector() from
generating invalid tsvectors.  It did not check for overly-long
lexemes (so that WordEntry.len fields could overflow), nor did it
check that the total "datalen" fits within MAXSTRPOS (so that
WordEntry.pos fields could overflow, and the number of entries
in the tsvector could be much more than the normal limit).
While the field overflows couldn't do anything much worse than
produce a corrupted tsvector value, a sufficiently large number
of tsvector entries could cause integer overflows in later
processing, such as tsvectorout.

Another important fix is to prevent tsvectorrecv() from accepting
invalid tsvectors.  The main problem there is that it did not
reject empty-string lexemes.  Hence, even though it did (mostly)
enforce the MAXSTRPOS limit, it could still produce a result
with an unreasonable number of tsvector entries, if they were
primarily empty strings.

Also, fix tsvectorout's calculation of its required output
buffer size: it was multiplying the string lengths by
pg_database_encoding_max_length() for no reason.  That contributed
to the risk of integer overflow there.  With valid tsvector input,
there's no risk, but there's still no reason to make the output
buffer several times bigger than needed.

I also tried to make a couple of related routines more robust,
and spent some effort on improving the comments in ts_type.h.
Also, standardize on a single spelling of the "string is too long
for tsvector" message, using %zu instead of an assortment of formats.
These changes aren't security per se but came out of inspecting the
code for problems.

Reported-by: Yuhang Wu <yuhang@depthfirst.com> and Zhenpeng Lin
Reported-by: Zheng Yu <zheng@depthfirst.com>
Reported-by: Hcamael <baiyjrh@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Backpatch-through: 14
Security: CVE-2026-14662
2026-08-10 06:38:17 -07:00
Tom Lane
12a6206864 Guard against overlength time zone abbreviations in to_char().
While typical abbreviations are only a few bytes long, a user-supplied
time_zone setting could specify a much longer abbreviation, enough to
overflow to_char's allocation of 12 bytes per format character. If so,
throw an error in the same style as commit 9241c84cb (CVE-2015-0241).

Reported-by: Hcamael <baiyjrh@gmail.com>
Reported-by: Amjad Shahzad <amjadshahzad2000@gmail.com>
Reported-by: Tan Zhen of AntAISecurityLab <TanZhen.AntAI@outlook.com>
Reported-by: Tomer Fichman <tomer@irregular.com>
Reported-by: Zheng Yu <zheng@depthfirst.com>
Reported-by: Amy Burnett (OpenAI Codex Security)
Reported-by: Rick de Jager <rick@v12.sh>
Reported-by: Heewon Song <asteria121@78researchlab.com>
Reported-by: Sylvie Mayer <smayer@cloudflare.com>
Reported-by: Aleksander Alekseev <aleksander@tigerdata.com>
Reported-by: Hillai Ben Sasson <hillai.bensasson@wiz.io>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Backpatch-through: 14
Security: CVE-2026-14669
2026-08-10 06:38:17 -07:00
Peter Eisentraut
3e85b223b0 Translation updates
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: e2e72c73155c6ef2002c25be726c102fd8243740
2026-08-10 12:17:04 +02:00
Tom Lane
6edf76ee3d Release notes for 18.5, 17.11, 16.15, 15.19, 14.24. 2026-08-09 12:52:47 -04:00
Etsuro Fujita
3704870b29 Drain pending asynchronous requests during ExecReScanAppend.
The logic for asynchronous Append assumes that pending requests made for
subplans of an Append are drained during ExecReScanAppend.  To ensure
that, commit 9e283fc85 modified postgresReScanForeignScan to drain such
a request if any, but failed to take into account that if such a request
was made for a subplan that is re-scanned with parameter changes or
pruned in the next round by runtime pruning, the postgres_fdw callback
function is called after ExecReScanAppend or never called, respectively.
This would cause such a request to remain even after ExecReScanAppend,
leading to incorrect results, an infinite loop, or an assertion failure.

To fix, modify ExecReScanAppend to, for each of the pending requests,
give the FDW a chance to drain that request using the existing
ForeignAsyncConfigureWait/ForeignAsyncNotify callback functions.  This
makes the change made to postgresReScanForeignScan useless, so remove it
as well.

Back-patch to v14 where asynchronous Append was added.

Reported-by: Alexander Korotkov <aekorotkov@gmail.com>
Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com>
Co-authored-by: Gleb Kashkin <g.kashkin@postgrespro.ru>
Co-authored-by: Etsuro Fujita <etsuro.fujita@gmail.com>
Reviewed-by: Alexander Pyhalov <a.pyhalov@postgrespro.ru>
Reviewed-by: Gleb Kashkin <g.kashkin@postgrespro.ru>
Discussion: https://postgr.es/m/CAPpHfduMOTnV5Zj2KGJ7zanL_10QvccZHtPUaDfJvBhsh9axnQ%40mail.gmail.com
Backpatch-through: 14
2026-08-07 17:30:03 +09:00
Michael Paquier
fc9283b215 Fix local pgstat entry leak on OOM during entry creation
When pgstat_init_entry() fails due to an OOM in the DSA allocation,
pgstat_get_entry_ref() cleaned up the shared hashtable but forgot to
remove the local reference that pgstat_get_entry_ref_cached() had
already inserted into pgStatEntryRefHash.

Missing this cleanup would leave a backend with a stale local cache
entry whose entry_ref points to a NULL shared_stats.  If
pgstat_gc_entry_refs() runs with this reference still around, it would
crash due to a pointer dereference.

The local reference is now removed before removing the shared entry,
the order being sensitive to pending interrupts.

Oversight in 8191e0c16a.

Author: Niall Newman <nn@turacolabs.com>
Discussion: https://postgr.es/m/2FDAA194-9CF3-4FD7-A450-F1A4BEB125F6@turacolabs.com
Backpatch-through: 15
2026-08-07 14:23:36 +09:00
Amit Kapila
3df129b8d7 Fix race condition in subscription TAP test 023_twophase_stream.
Buildfarm member olingo intermittently failed this test, timing out while
waiting for the subscriber log to report an ERROR because
max_prepared_transactions is zero there. The test captured the log offset
only after issuing the publisher's
BEGIN/INSERT/PREPARE TRANSACTION/COMMIT PREPARED sequence.

Since streaming is enabled, the subscriber can receive and apply the
transaction, and log the expected ERROR, before that publisher SQL command
even returns, i.e. before the test captures the offset. The subsequent
wait_for_log() calls then searched only from a point after the message had
already been written, and timed out waiting for it.

Fix by moving the offset capture to before the publisher's transaction is
issued, ensuring it always precedes the point where the ERROR can appear
in the subscriber log.

Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 16, where test was introduced
Discussion: https://postgr.es/m/c43753d8-5265-4f77-83ff-9b1167276ec5@gmail.com
2026-08-06 11:20:26 +05:30
Álvaro Herrera
8acfaa12a4 Fix calculating length of match to localized month/weekday names
seq_search_localized() returns the length of the matching prefix in
*len, but because it internally case-folds the inputs, it gets
confused on the length. The caller expects to get the length of the
prefix in the original string, but what it actually returns is the
length of the prefix after case-folding, which can be different if the
case-folded characters have different byte-length than the original,
or with ICU, if the case-folding changes the number of characters
(e.g. "ß", the German double s).

To fix, once we have determined that we have a match, work harder to
find the match's length in the original string.  This adds some
overhead, but the strings are expected to be short.

The function does "case-folding" by converting a string to upper-case,
then to lower-case, which is a little ugly given that we have
dedicated functions for case-folding nowadays. But switching to that
doesn't seem appropriate to backpatch in a security fix, and that's
not available in older stable versions, anyway.

Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Reported-by: Xint Code
Reviewed-by: Jeff Davis <pgsql@j-davis.com>
2026-08-05 11:40:39 +02:00
Fujii Masao
9484169ba0 doc: Update XID wraparound error example
Commit edee0c621d, and the equivalent v17 commit f2353dd717,
changed the runtime XID wraparound messages to use "transaction IDs"
terminology, but one corresponding error example in maintenance.sgml
still used the older XID wording.

Update that documentation example in line with the current runtime
message.

Backpatch to v17, where the runtime messages were changed.

Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Yugo Nagata <nagata@sraoss.co.jp>
Discussion: https://postgr.es/m/CAHGQGwHTN-Xc5iDtbzNSjfxuab5Y9qAArw8cB4PrrDJpZ+1fgA@mail.gmail.com
Backpatch-through: 17
2026-08-05 11:37:43 +09:00
Álvaro Herrera
1b6c99d96a pg_surgery: Fix infinite loop on large TID arrays
heap_force_common() tracked the current position in the caller-supplied
tid[] using OffsetNumber, which is only 16 bits wide, so when the array
held more than 65535 entries, the updated index wrapped around and the
outer loop never reached the exit condition.  A SQL call with a
sufficiently large TID array would then run until interrupted.

Fix by tracking the tid[] position using int instead of OffsetNumber.
A regress case based on the report is included.

Author: Andrey Rachitskiy <pl0h0yp1@gmail.com>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Reported-by: Yuelin Wang <1217816127@qq.com>
Backpatch-through: 14
Bug: #19607
Discussion: https://postgr.es/m/19607-2f256a66481c514b@postgresql.org
2026-08-04 11:44:11 +02:00
Álvaro Herrera
18006c1bd6 Fix ALTER COLUMN ... DROP EXPRESSION with subpartitions
Per commit 8bf6ec3ba3, a column can be GENERATED only if it is such in
the whole inheritance tree.

For this reason, ATPrepDropExpression refuses to be called with ONLY on
a partitioned table. To detect this, the current implementation checks
whether recurse is set to false and the rel has direct children.

Recursion is implemented with ATSimpleRecursion, which calls ATPrepCmd
with recurse = false for every node in the tree. Inner nodes (for
example a partition which itself has subpartitions) then fail the check,
accidentally preventing the command from working on inheritance trees of
depth > 2.

This commit fixes it by also checking that we're at the top level of the
recursive calls using the recursing parameter, which is always true when
called through ATSimpleRecursion, always false when invoked on the root
rel.

Also, remove a comment claiming that DROP EXPRESSION could be
implemented with some effort.  It cannot, as the commit message for
8bf6ec3ba3 explains.

Author: Alberto Piai <alberto.piai@gmail.com>
Backpatch-through: 14
Discussion: https://postgr.es/m/DHMT78XOD8BK.341V3H87KZ7NO@gmail.com
2026-08-04 09:06:46 +02:00
David Rowley
1416f304d2 Fix missing money overflow checks for INT64_MIN / -1
Similar to what 1f7cb5c30 did for the INT types, protect against
overflow when dividing the lowest possible money value by -1.  This
cannot be represented on a two's complement machine.

Without this check, the result depends on the machine, and in the worst
case, could result in a crash.  With the fix installed, this will now
result in:

ERROR:  money out of range

Bug: #19585
Author: Andrey Rachitskiy <pl0h0yp1@gmail.com>
Reported-by: Michael Malis <malis@pgrust.com>
Reviewed-by: Tristan Partin <tristan@partin.io>
Reviewed-by: Rafia Sabih <rafia.pghackers@gmail.com>
Discussion: https://postgr.es/m/19586-bb603bf5ad9934dd%40postgresql.org
Discussion: https://postgr.es/m/CAB8bMisnXJVXte6s3kUOpuuAY9%3D9kehG6MMX-%2BTQoFsSGan22Q%40mail.gmail.com
Backpatch-through: 14
2026-08-04 18:00:49 +12:00
David Rowley
cce758797f Fix missing MCXT_ALLOC_NO_OOM handling in MemoryContextAllocAligned
Fix missing NULL check in MemoryContextAllocAligned().  The underlying
call to MemoryContextAllocExtended() could return NULL when
flags contains MCXT_ALLOC_NO_OOM and the underlying malloc fails.

There are no current callers using MemoryContextAllocAligned() that pass
the MCXT_ALLOC_NO_OOM in core, so no live bug fix in core here. However,
an extension might use this pattern, so we'd better fix.

Fix this so we correctly pass the NULL to the caller rather than trying
to write to a NULL memory address.

This also fixes the same bug in AlignedAllocRealloc(), which is also
unused in core.

Backpatch to v16, where these functions first appeared.

Author: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/07DAC4C3-120D-4F3C-8FEE-BA236F7E9C1D@gmail.com
Backpatch-through: 16
2026-08-04 16:10:18 +12:00
Jeff Davis
25e54cec72 Fix lock release for role membership grants in DROP OWNED BY.
Commit 6566133c5f added a case for AuthMemRelationId in
AcquireDeletionLock(), but not ReleaseDeletionLock(). The fall-through
case would go to UnlockDatabaseObject(), which would raise a WARNING;
and the lock would be retained until the end of the transaction.

Add the missing branch.

Discussion: https://postgr.es/m/2487ddcd737d4fc8e408e87aa9ad4365eed3bbb3.camel@j-davis.com
Backpatch-through: 16
2026-08-03 12:25:41 -07:00
Jeff Davis
a961b102cd Do not log subscription conninfo.
Logging connection information, even at DEBUG1, creates unnecessary
risks. Remove the entire log message because it had no other useful
content.

Addresses finding 14 in report from linked discussion.

Reported-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20260710195902.4f.noahmisch@microsoft.com
Backpatch-through: 14
2026-08-03 11:35:50 -07:00
Tom Lane
634a8dcb8f Tighten up TS dictionary cache entry creation.
In the not-too-likely scenario where we successfully created a hash
table entry for a TS dictionary, but then failed to make a small
memory context for it, we left the hash entry in existence but with
a garbage value for dictCtx.  This confused the code the next time
through, leading to a crash.  Rearrange things so that we leave
the hash entry in a well-defined state with dictCtx == NULL, and
then the next try knows it still needs to make a memory context.

Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/0f3ddeb5-0dbd-479c-9d0e-ae254758e624@gmail.com
Backpatch-through: 14
2026-08-02 16:49:18 -04:00
Tom Lane
5fdea3aa32 Fix memory-safety bugs in the ispell/hunspell dictionary loader.
Allocate CompoundAffix with room for its terminator, initialize the
old-format flag buffer before NIAddAffix(), and reject incomplete or
missing Hunspell AF aliases.  None of these errors would be likely to
trigger on real dictionary files, accounting for the lack of previous
reports; but they're certainly bugs.

Bug: #19595
Reported-by: Michael Malis <michaelmalis2@gmail.com>
Author: Andrey Rachitskiy <pl0h0yp1@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19595-7dc18b4e212c4757@postgresql.org
Backpatch-through: 14
2026-08-02 13:22:39 -04:00
Tom Lane
669438aed4 Update time zone data files to tzdata release 2026c.
Alberta (America/Edmonton) moved to permanent UTC-06 on
2026-06-18, which will affect their clocks beginning on 2026-11-01.
For lack of any clarity on the point, assume their TZ abbreviation
will be CST from that time forward.

Morocco (Africa/Casablanca) will move to permanent UTC+00,
without daylight saving time transitions, on 2026-09-20.

Backpatch-through: 14
2026-08-02 11:26:30 -04:00
Robert Haas
499d9eabb5 Prevent walsummarizer from getting stuck at a timeline switch.
As previously coded, walsummarizer only wants to read WAL from a file
where the TimeLineID in the filename exactly matches the TimeLineID being
summarized. But in some cases, when a timeline switch occurs, the WAL file
from the old timeline is not archived, because it's never completely
filled, so the only way to obtain the contents of that last partial
segment is to read from the first segment on the new timeline. Teach
WAL summarizer to do that, and add a test case to make sure that it
works.

Reported-by: Nick Ivanov <nick.ivanov@enterprisedb.com>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Tested-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Srinath Reddy Sadipiralla <srinath2133@gmail.com>
Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Thom Brown <thom@linux.com>
Discussion: http://postgr.es/m/CA+Tgmobr27GpKDZx3_ezW2+C5_g18i+jSK3sGF_cR-_ESv5N5A@mail.gmail.com
Backpatch-through: 17
2026-07-31 11:57:44 -04:00
Nathan Bossart
288d4e83f1 Fix autovacuum's database sorting.
When db_comparator() was updated to use pg_cmp_s32(), the arguments
were listed in the wrong order.  This caused autovacuum to sort the
databases by their scores in ascending order instead of descending
order.  To fix, swap the arguments to pg_cmp_s32().

Oversight in commit 3b42bdb471.

Reported-by: Хамидуллин Рустам <r.khamidullin@postgrespro.ru>
Author: Хамидуллин Рустам <r.khamidullin@postgrespro.ru>
Discussion: https://postgr.es/m/5c5a7984-b149-b505-7ad9-2a7766c65b55%40postgrespro.ru
Backpatch-through: 17
2026-07-31 10:34:40 -05:00
David Rowley
31f2acde53 Fix issue with RANGE's DEFAULT partition pruning
Partition pruning for RANGE-partitioned tables could mistakenly prune
the DEFAULT partition in some cases when it was not valid to do so,
which could lead to rows missing from query results.

The only known cases where this could happen is when combining pruning
steps from an IS NOT NULL clause with other steps that matched to the
DEFAULT partition.  This could occur due to RANGE partitioned tables
having two distinct internal representations for marking if the DEFAULT
partition should be scanned.  The IS NOT NULL steps would mark the
"scan_default" boolean, but other steps created for different purposes
could mark a bound_offset Bitmapset, which would ultimately translate into
also scanning the default partition.  This could all fail after multiple
steps were combined with a combine intersect operator, as that will
intersect the bound_offset bits and only set scan_default if all pruning
steps have that flag set.  When both input steps to the intersect operator
had different representations of whether to scan the DEFAULT partition,
the resulting intersect step result would contain neither representation.

Here, we fix this by having the IS NOT NULL pruning result mark the
bound_offsets so that it uses both representations to mark that the
DEFAULT partition must be scanned.

Reported-by: Jacob Brazeal <jacob.brazeal@gmail.com>
Diagnosed-by: Jacob Brazeal <jacob.brazeal@gmail.com>
Author: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CA+COZaDXrfTaBjLE=Z79MTaH6Xun1V4PeKxLvCNv8mXS8wn0rw@mail.gmail.com
Backpatch-through: 14
2026-07-31 15:38:10 +12:00
Amit Kapila
41f1cd1d26 Skip SUBSCRIPTION TABLE TOC entries with --no-subscriptions.
pg_dump in --binary-upgrade mode emits "SUBSCRIPTION TABLE" TOC entries to
preserve pg_subscription_rel state across pg_upgrade.  When such a dump
was restored with --no-subscriptions, _tocEntryRequired() skipped the
"SUBSCRIPTION" entry but not the associated "SUBSCRIPTION TABLE" entries,
so the restore would try to apply subscription-relation state for a
subscription that was never created.

Skip "SUBSCRIPTION TABLE" entries as well when no_subscriptions is set.

This can happen when pg_subscription_rel has entries, the dump is taken
with --binary-upgrade, and it is restored with --no-subscriptions.

Reported-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Shlok Kyal <shlok.kyal.oss@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 17, where it was introduced
Discussion: https://postgr.es/m/OS9PR01MB121493DA4C1A7748B11A646D8F5C02@OS9PR01MB12149.jpnprd01.prod.outlook.com
2026-07-30 11:18:39 +05:30
Daniel Gustafsson
e1885a875c doc: Add a note that refint will be removed in v20
refint has been removed from the spi contrib module in v20.  Add a note
to the documentation of the still-supported back branches so that users
are aware the module is going away.

Author: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
Reported-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAJTYsWUHq8Ohc6-N-xamOPYz-q3qUYMtwQX-1=Zi=5N1Q_GSEQ@mail.gmail.com
Backpatch-through: 14
2026-07-29 21:51:46 +02:00
Álvaro Herrera
2cf28d1b9a Fix cascading standby reconnect failure after archive fallback
A cascading standby could fail to reconnect to its upstream standby with
"requested starting point ... is ahead of the WAL flush position" after
falling back to archive recovery.  This happened because archive
recovery processes whole segment files, so after replaying a segment the
cascade's next read position lands at the start of the following
segment, which is ahead of the upstream's flush position reported by
GetStandbyFlushRecPtr() (still inside the just-replayed segment).

Fix by having the walreceiver check the upstream's current WAL flush
position via IDENTIFY_SYSTEM before issuing START_REPLICATION.
IDENTIFY_SYSTEM already returns this position (as xlogpos), but
walrcv_identify_system() previously discarded it; now we have a use for
it.  If the requested start point exceeds the upstream's flush position
on the same timeline, the walreceiver waits for
wal_retrieve_retry_interval and retries.

The wait is limited to gaps of at most one WAL segment, which is the
expected case from the segment-granularity of archive recovery.  Larger
gaps indicate the upstream is genuinely behind, so START_REPLICATION is
allowed to proceed (and fail) normally, letting the startup process fall
back to other WAL sources.  The first wait is logged at LOG level;
subsequent waits are demoted to DEBUG1 to avoid log noise.  The
walreceiver honors wal_receiver_timeout during the wait, so it will exit
if the upstream doesn't catch up in time.

To preserve ABI compatibility on back branches, the flush position from
IDENTIFY_SYSTEM is communicated via a new global variable
(WalRcvIdentifySystemLsn) rather than changing the signature of
walrcv_identify_system().

The bug was introduced in Postgres 9.3 by commit abfd192b1b, which
added a flush-position check in StartReplication() that rejects requests
ahead of the upstream server's WAL flush position.

Author: Marco Nenciarini <marco.nenciarini@enterprisedb.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Backpatch-through: 14
Discussion: https://postgr.es/m/CA+nrD2cTuTkkX5WXVZengTYYZbAO6zV8K+Tri-R0fbLFuoyMBA@mail.gmail.com
2026-07-29 17:15:45 +02:00
Tom Lane
26d6b7dc9e Fix planner's nullability/strictness logic for ScalarArrayOpExpr.
find_nonnullable_rels and find_nonnullable_vars mistakenly treated a
ScalarArrayOpExpr that could return FALSE as strict, but that's okay
only at top level of a qual expression; further down, we've got to
insist on a guaranteed-NULL result.  The result was that we could draw
mistaken conclusions about whether outer joins can be simplified, if
the decision hinged on a non-top-level ScalarArrayOpExpr with a
potentially-empty array argument.

I believe this error dates to commit 72a070a36, which taught
find_nonnullable_rels to descend into non-top-level parts of qual
expressions.  is_strict_saop (added earlier by 72153c058) already had
enough intelligence to do the case correctly, but it wasn't passed the
proper flag, ie "top_level" needs to be passed for "falseOK".
e006a24ad copied that mistake into find_nonnullable_vars.

Later, over-eager refactoring in commit 2f153ddfd broke
contain_nonstrict_functions' handling of ScalarArrayOpExpr by treating
it as though it were no different from an OpExpr.  It is, because
we must also prove the array is non-empty before concluding that the
expression is strict.  This could result in misclassifying an
expression as strict when it is not, leading to assorted planning
mistakes such as inlining a SQL function that shouldn't be inlined.
We can almost fix this by just re-adding the previous handling of
ScalarArrayOpExpr in that function, but doing only that would lead to
also calling check_functions_in_node() and thus redundantly checking
the operator's strictness.  Avoid that by turning the if-series into
an else-if chain, as it arguably should have been all along.

The reason these errors have escaped detection for decades is that
they are exposed only in arcane corner cases.  ScalarArrayOpExpr with
an empty array isn't typical usage, and even when that's possible
several other conditions apply before the planner can reach a mistaken
conclusion.  While it's possible to build test cases demonstrating
these mistakes, I (tgl) judged them too indirect and special-purpose
to justify consuming regression test cycles forevermore.

Author: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAJTYsWV3vqRJmST-gv1NsXEef-zOnjVJpYS910aBaiuMij4nFg@mail.gmail.com
Discussion: https://postgr.es/m/CAJTYsWWcLGmz0f8_QPP_Liq-fc7-geiFSCdqoq3XGeRHPPsWeA@mail.gmail.com
Backpatch-through: 14
2026-07-28 16:09:04 -04:00
Masahiko Sawada
8c4519c71a Fix logical decoding of empty prepared transactions.
A two-phase transaction that is assigned an XID but produces no change
to be decoded -- for example, one that only acquires row locks via
SELECT ... FOR SHARE -- has no base snapshot in the reorder
buffer. ReorderBufferReplay() already skips such a transaction at
PREPARE time and never invokes the begin_prepare/change/prepare
callbacks for it, but ReorderBufferFinishPrepared() still called the
commit_prepared (or rollback_prepared) callback. As a result a
spurious COMMIT/ROLLBACK PREPARED was sent to the output plugin with
no preceding PREPARE. For the built-in subscriber this breaks
replication (the apply worker fails to find the prepared transaction),
and test_decoding could even crash.

Fix this by detecting an empty transaction (base_snapshot == NULL) in
ReorderBufferFinishPrepared() and cleaning it up without invoking the
commit/rollback prepared callbacks, mirroring the existing empty
transaction handling in ReorderBufferReplay().

On v18 and newer versions, commit 072ee847ad changed
ReorderBufferPrepare() to send the prepare whenever it had not already
been sent, which also fires for empty transactions and emits a
spurious PREPARE. On those branches ReorderBufferPrepare() is
therefore additionally guarded with base_snapshot != NULL. This guard
and the Assert(!rbtxn_sent_prepare()) added in
ReorderBufferFinishPrepared(), are not necessary on v17 and older
versions: there ReorderBufferPrepare() only sends a prepare for
concurrently-aborted transactions (which never applies to an empty
transaction) and the RBTXN_SENT_PREPARE flag does not exist.

Back-patch to v14, where decoding of two-phase transactions was
introduced.

Bug: #19556
Reported-by: Alexander Kozhemyakin <a.kozhemyakin@postgrespro.ru>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/19556-daa6d7ea65054d48@postgresql.org
Backpatch-through: 14
2026-07-28 12:33:40 -07:00
Masahiko Sawada
dcbc96685d Fix pg_get_publication_tables() failure with concurrent DROP TABLE.
pg_get_publication_tables() collects the OIDs of the published tables
on its first call, without locking them, and then reopens each table
later, once per result row, to compute its column list and fetch its
row filter. The reopen used table_open(), which errors out with "could
not open relation with OID" if the table has been dropped in the
meantime. This could happen for any published table without an
explicit column list, which is every table in FOR ALL TABLES and FOR
TABLES IN SCHEMA publications, but also FOR TABLE entries without a
column list. The failure is common in environments where many tables
are created and dropped while publication tables are being queried,
e.g. by table synchronization on a subscriber.

Fix by opening every table with try_table_open(), which returns NULL
if the relation no longer exists, and skipping the table in that
case. Concurrently dropped tables are thus simply absent from the
result set, which is the expected point-in-time behavior.

As a side effect, tables with an explicit column list, which were
previously returned without being opened, are now also locked with
AccessShareLock, so the function can block behind concurrent DDL on
such tables where it previously did not.

Backpatch to v16, where we added the table_open() call in
pg_get_publication_tables().

Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Ajin Cherian <itsajin@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://www.postgresql.org/message-id/CALj2ACVYYooWH-5tJ6cPKkU%2BmutVxwb_z4S%2BqAi-zdrFqxXE2Q%40mail.gmail.com
Backpatch-through: 16
2026-07-28 10:39:47 -07:00
Alexander Korotkov
ba5e463295 Restore vacuum_delay_point() in GIN posting-tree leaf vacuum
Commit fd83c83d09 turned the recursive posting-tree cleanup in
ginVacuumPostingTreeLeaves() into an iterative sweep that follows the
tree's leaf pages via their rightlinks.  The recursive version called
vacuum_delay_point() while processing the tree, but that call was removed
and never re-added to the new loop.  As that commit only set out to fix a
deadlock, the removal appears to have been unintentional.

Consequently the leaf-page sweep of a single posting tree runs with no
vacuum_delay_point(), and therefore no CHECK_FOR_INTERRUPTS().  A posting
tree stores all the TIDs for one indexed key, so for a frequently
occurring key it can span a large number of leaf pages.  While such a
tree is being vacuumed the operation ignores vacuum_cost_delay and does
not respond to query cancellation or statement_timeout; an autovacuum
worker likewise cannot be interrupted mid-sweep when another backend
requests a conflicting lock.

Restore the call, placed after the current page has been unlocked and
released so that no buffer content lock is held across a potential delay
(cf. 21c27af65f).  The sibling loops in ginbulkdelete() and
ginvacuumcleanup() already call vacuum_delay_point() once per page.

Author: Paul Kim <mok03127@gmail.com>
Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Reviewed-by: solai v <solai.cdac@gmail.com>
Discussion: https://postgr.es/m/178447127453.110.12276981925360691905%40mail.gmail.com
Backpatch-through: 14
2026-07-28 10:56:27 +02:00
Michael Paquier
28269fed66 Fix propagation of indimmediate flag in index_create_copy()
index_create_copy is used to create copy definitions of existing indexes.
Currently, it passes 0 as constr_flags to index_create(), which results
in the copied index to always be created as immediate (indimmediate set
to true).  For deferrable unique constraints, it means that the
transient index used during the phase 2 of REINDEX CONCURRENTLY forces
immediate constraint checks on concurrent inserts, which can cause
unexpected constraint violations based on the definition of the parent
table, inconsistently set in the copied index.

To fix this without violating the contract of constr_flags (which should
only be used when creating constraints) and without relaxing the strict
assertion in index_create(), this introduces a new index creation flag:
INDEX_CREATE_DEFERRABLE.  If set, a copied index's indimmediate is set
to false, meaning that unique constraints are not enforced immediately
on insertion, but at transaction commit time.

An isolation test for REINDEX CONCURRENTLY is added, based on an
injection point waiting after phase 1 of the operation, where an index
copy has been built and is able to accept DMLs for its validation in
phase 2.  The test is tentatively backpatched down to v17.
INJECTION_POINT() is outside a transaction context, which should be fine
on HEAD since 8daeaa9b64 but I suspect may cause issues in v19 and
older branches due to the wait facility depending on condition variables
and a DSM setup, but let's see what the buildfarm tells.

Author: Nitin Motiani <nitinmotiani@google.com>
Discussion: https://postgr.es/m/CAH5HC97JmjPpgiQOqW9xm8qXhNiu7zZ1Qh+FfhEESJuDv69kuQ@mail.gmail.com
Backpatch-through: 14
2026-07-28 08:35:14 +09:00
Peter Geoghegan
8434c93859 Fix another empty nbtree index SSI race.
Commit f9b7fc65 fixed a race when predicate-locking completely empty
btrees: without a buffer lock held, a matching key could be inserted
between _bt_search and the PredicateLockRelation call, so the scan would
miss concurrently inserted tuples while the writer wouldn't see the
reader's predicate lock.  That commit only fixed _bt_first's _bt_search
path, though.  Scans without useful insertion scan keys return early
from _bt_first via _bt_endpoint, which still didn't recheck if the
relation was empty.

To fix, add handling to _bt_endpoint that is analogous to the handling
added to _bt_search by commit f9b7fc65.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzkNoTn3yXY0iGkSuavJ+sL8EROf+kitW+_2v2tJVWuKmA@mail.gmail.com
Backpatch-through: 14
2026-07-25 12:01:30 -04:00
Fujii Masao
41949c6f32 psql: Allow pg_read_all_stats to see database size in \l+
pg_database_size() allows access to users who have either CONNECT
privilege on the target database or privileges of the pg_read_all_stats
role. However, previously, psql's \l+ checked only for CONNECT,
so users with privileges of pg_read_all_stats still saw "No Access" for
databases they could not connect to.

Fix this by making \l+ also check
pg_has_role('pg_read_all_stats', 'USAGE'), matching
pg_database_size()'s permission rules.

For back branches, emit the pg_read_all_stats check only when
connected to PostgreSQL 10 or later, since earlier releases do not have
that predefined role.

Backpatch to all supported versions.

Author: Christoph Berg <myon@debian.org>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/amCo6qRmnfPVk4-V@msg.df7cb.de
Backpatch-through: 14
2026-07-25 19:10:22 +09:00
Michael Paquier
821a4b4d07 injection_points: Clear waiter slot on error and exit
injection_wait() only clears its slot in the waiter array after the
wait loop finishes.  When the waiting query is canceled or the backend
is terminated (wait look has a CHECK_FOR_INTERRUPS), the slot leaks.
Later wakeups of the same point then bump the counter of the leaked slot
instead of the real waiter, that sleeps forever.  Repeated leaks can
exhaust all the slots.

The code is changed so as the waiting loop is wrapped with
PG_ENSURE_ERROR_CLEANUP, so as the injection point slots, that are
shared resources, can be cleaned up on ERROR as much as a FATAL.

An isolation test is added: cancel one waiter, terminate another waiter,
then check that a later waiter still receives a wakeup.  Without the
fixed code, the test would fail on timeout.

Author: Zsolt Parragi <zsolt.parragi@percona.com>
Discussion: https://postgr.es/m/CAN4CZFO+KF=cc0-iEg28RhqRBp_fTs6D4b8b7D7DB-pGYP3Ccg@mail.gmail.com
Backpatch-through: 17
2026-07-23 14:37:48 +09:00