test_predtest() neglected to consider the possibility that
SPI_plan_get_cached_plan would return NULL. This led to a core
dump if the input (incorrectly) contains more than one SQL
command.
While here, let's expend more than zero effort on the error
message for this case and nearby ones.
Per (half of) bug #18483 from Alexander Kozhemyakin.
Back-patch to all supported branches, not because this is
very significant (it's merely test scaffolding) but to make
our world a bit safer for fuzz testing.
Discussion: https://postgr.es/m/18483-30bfff42de238000@postgresql.org
Normally this case isn't even reachable by non-superusers, since
permissions checks prevent naming such a table. However, it is
possible to make it happen by altering a parent table whose child
is another session's temp table.
We definitely can't support any such ALTER that requires modifying
the contents of such a table, since we lack access to the other
session's temporary-buffer pool. But there seems no good reason
to allow it even if it'd only require changing catalog contents.
One reason not to allow it is that we'd rather not expose the
implementation-dependent behavior of whether a specific ALTER
requires touching the table contents. Another is that there may
be (in future, even if not today) optimizations that assume that
a session's own temp tables won't be modified by other sessions.
Hence, add a RELATION_IS_OTHER_TEMP() check to all the places
where ALTER TABLE currently does CheckTableNotInUse(). (I looked
through all other callers of CheckTableNotInUse(), and they seem
OK already.)
Per bug #18492 from Alexander Lakhin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18492-c7a2634bf4968763@postgresql.org
If the CALL is within an atomic context (e.g. there's an outer
transaction block), _SPI_execute_plan should acquire a fresh snapshot
to execute any such functions with. We failed to do that and instead
passed them the Portal snapshot, which had been acquired at the start
of the current SQL command. This'd lead to seeing stale values of
rows modified since the start of the command.
This is arguably a bug in 84f5c2908: I failed to see that "are we in
non-atomic mode" needs to be defined the same way as it is further
down in _SPI_execute_plan, i.e. check !_SPI_current->atomic not just
options->allow_nonatomic. Alternatively the blame could be laid on
plpgsql, which is unconditionally passing allow_nonatomic = true
for CALL/DO even when it knows it's in an atomic context. However,
fixing it in spi.c seems like a better idea since that will also fix
the problem for any extensions that may have copied plpgsql's coding
pattern.
While here, update an obsolete comment about _SPI_execute_plan's
snapshot management.
Per report from Victor Yegorov. Back-patch to all supported versions.
Discussion: https://postgr.es/m/CAGnEboiRe+fG2QxuBO2390F7P8e2MQ6UyBjZSL_w1Cej+E4=Vw@mail.gmail.com
Previously, when considering LIMIT pushdown, postgres_fdw failed to
check whether the query has this clause, which led to pushing false
LIMIT clauses, causing incorrect results.
This clause has been supported since v13, so we need to do a
remote-version check before deciding that it will be safe to push such a
clause, but we do not currently have a way to do the check (without
accessing the remote server); disable pushing such a clause for now.
Oversight in commit 357889eb1. Back-patch to v13, where that commit
added the support.
Per bug #18467 from Onder Kalaci.
Patch by Japin Li, per a suggestion from Tom Lane, with some changes to
the comments by me. Review by Onder Kalaci, Alvaro Herrera, and me.
Discussion: https://postgr.es/m/18467-7bb89084ff03a08d%40postgresql.org
Before the v13-era commit 913bbd88d, check_sql_fn_retval fails to
resolve polymorphic output types and then just throws up its hands and
assumes the check will be made at runtime. I think that's true for
ordinary functions returning RECORD, but it doesn't happen in CALL,
potentially resulting in crashes if the actual output of the SQL
procedure's SELECT doesn't match the type inferred from polymorphism.
With a little bit of rearrangement, we can use get_call_result_type
instead of get_func_result_type and thereby infer the correct types.
I'm still unwilling to back-patch all of 913bbd88d, so if the types
don't match you'll get an error rather than perhaps silently inserting
a cast as v13 and later can. That's consistent with prior behavior
though, so it seems fine.
Prior to 70ffb27b2, you'd typically get other errors due to other
shortcomings of CALL's management of polymorphism. Nonetheless,
this is an independent bug.
Although there is no bug in v13 and up, it seems prudent to add
the test case for this to the newer branches too. It's clearly
an under-tested area.
Per report from Andrew Bille.
Discussion: https://postgr.es/m/CAJnzarw9EeWHAQRm76dXd=7j+rgw6ERqC=nCay8jeFqTwKwhqQ@mail.gmail.com
The documentation for POSIX semaphores is missing a reference to
max_wal_senders. This commit fixes that in the same way that
commit 4ebe51a5fb fixed the same issue in the documentation for
System V semaphores.
Discussion: https://postgr.es/m/20240517164452.GA1914161%40nathanxps13
Backpatch-through: 12
In a procedure or function returning tuple, we use that function to
parse the Tcl script's result, which is supposed to be a Tcl list.
If it isn't, you get an error. Commit 26abb50c4 incautiously
supposed that we could use throw_tcl_error() to report such an error.
That doesn't actually work, because low-level functions like
Tcl_ListObjGetElements() don't fill Tcl's errorInfo variable.
The result is either a null-pointer-dereference crash or emission
of misleading context information describing the previous Tcl error.
Back off to just reporting the interpreter's result string, and
improve throw_tcl_error()'s comment to explain when to use it.
Also, although the similar code in pltcl_trigger_handler() avoided
this mistake, it was using a fairly confusing wording of the
error message. Improve that while we're here.
Per report from A. Kozhemyakin. Back-patch to all supported
branches.
Erik Wienhold and Tom Lane
Discussion: https://postgr.es/m/6a2a1c40-2b2c-4a33-8b72-243c0766fcda@postgrespro.ru
The formulas for SEMMNI and SEMMNS do not include the archiver
process, which was converted to an auxiliary process in v14, and
the WAL summarizer process, which was introduced in v17. This
commit corrects these formulas and adds a missing reference to
max_wal_senders nearby. Since this section of the documentation
tends to be incorrect quite often, we should likely give up on
documenting the exact formulas in favor of something less fragile,
but that is left as a future exercise.
Reported-by: Sami Imseih
Reviewed-by: Sami Imseih
Discussion: https://postgr.es/m/20240517164452.GA1914161%40nathanxps13
Backpatch-through: 12
Coverity complains that ECPGdebug is accessing debugstream without
holding debug_mutex, which is a fair complaint: we should take
debug_mutex while changing the settings ecpg_log looks at.
In some branches it also complains about unlocked use of simple_debug.
I think it's intentional and safe to have a quick unlocked check of
simple_debug at the start of ecpg_log, since that early exit will
always be taken in non-debug cases. But we should recheck
simple_debug after acquiring the mutex. In the worst case, calling
ECPGdebug concurrently with ecpg_log in another thread could result
in a null-pointer dereference due to debugstream transiently being
NULL while simple_debug isn't 0.
This is largely hypothetical, since it's unlikely anybody uses
ECPGdebug() at all in the field, and our own regression tests
don't seem to be hitting the theoretical race conditions either.
Still, if we're going to the trouble of having mutexes here, we ought
to be using them in a way that's actually safe not just almost safe.
Hence, back-patch to all supported branches.
Parameter column_name must be an existing column because ALTER
MATERIALIZED VIEW cannot add new columns. The old description was
likely copied from ALTER TABLE.
Author: Erik Wienhold
Discussion: https://postgr.es/m/6880ca53-7961-4eeb-86d5-6bd05fc2027e@ewie.name
Backpatch-through: 12
transformTableLikeClause believed that it could process extended
statistics immediately because "the representation of CreateStatsStmt
doesn't depend on column numbers". That was true when extended stats
were first introduced, but it was falsified by the addition of
extended stats on expressions: the parsed expression tree is fed
forward by the LIKE option, and that will contain Vars. So if the
new table doesn't have attnums identical to the old one's (typically
because there are some dropped columns in the old one), that doesn't
work. The CREATE goes through, but it emits invalid statistics
objects that will cause problems later.
Fortunately, we already have logic that can adapt expression trees
to the possibly-new column numbering. To use it, we have to delay
processing of CREATE_TABLE_LIKE_STATISTICS into expandTableLikeClause,
just as for other LIKE options that involve expressions.
Per bug #18468 from Alexander Lakhin. Back-patch to v14 where
extended statistics on expressions were added.
Discussion: https://postgr.es/m/18468-f5add190e3fa5902@postgresql.org
We are capable of optimizing MIN() and MAX() aggregates on indexed
columns into subqueries that exploit the index, rather than the normal
thing of scanning the whole table. When we do this, we replace the
Aggref node(s) with Params referencing subquery outputs. Such Params
really ought to be included in the per-plan-node extParam/allParam
sets computed by SS_finalize_plan. However, we've never done so
up to now because of an ancient implementation choice to perform
that substitution during set_plan_references, which runs after
SS_finalize_plan, so that SS_finalize_plan never sees these Params.
The cleanest fix would be to perform a separate tree walk to do
these substitutions before SS_finalize_plan runs. That seems
unattractive, first because a whole-tree mutation pass is expensive,
and second because we lack infrastructure for visiting expression
subtrees in a Plan tree, so that we'd need a new function knowing
as much as SS_finalize_plan knows about that. I also considered
swapping the order of SS_finalize_plan and set_plan_references,
but that fell foul of various assumptions that seem tricky to fix.
So the approach adopted here is to teach SS_finalize_plan itself
to check for such Aggrefs. I refactored things a bit in setrefs.c
to avoid having three copies of the code that does that.
Back-patch of v17 commits d0d44049d and 779ac2c74. When d0d44049d
went in, there was no evidence that it was fixing a reachable bug,
so I refrained from back-patching. Now we have such evidence.
Per bug #18465 from Hal Takahara. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18465-2fae927718976b22@postgresql.org
Discussion: https://postgr.es/m/2391880.1689025003@sss.pgh.pa.us
Commit 695b4a113a added a dependency on retrieving oldestxid from
pg_control, which only exists in 9.0 and onwards, but the check for
8.4 as the oldest version was retained. Since there has been few if
any complaints of 8.4 upgrades not working, fix by setting 9.0 as
the oldest version supported rather than resurrecting 8.4 support.
Backpatch to all supported versions.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1973418.1657040382@sss.pgh.pa.us
Backpatch-through: v12
Specifically, it terminates a background worker even if the caller
couldn't terminate the background worker with pg_terminate_backend().
Commit 3a9b18b309 neglected to update
this. Back-patch to v13, which introduced DROP DATABASE FORCE.
Reviewed by Amit Kapila. Reported by Kirill Reshke.
Discussion: https://postgr.es/m/20240429212756.60.nmisch@google.com
Most of the infrastructure for procedure arguments was already
okay with polymorphic output arguments, but it turns out that
CallStmtResultDesc() was a few bricks shy of a load here. It thought
all it needed to do was call build_function_result_tupdesc_t, but
that function specifically disclaims responsibility for resolving
polymorphic arguments. Failing to handle that doesn't seem to be
a problem for CALL in plpgsql, but CALL from plain SQL would get
errors like "cannot display a value of type anyelement", or even
crash outright.
In v14 and later we can simply examine the exposed types of the
CallStmt.outargs nodes to get the right type OIDs. But it's a lot
more complicated to fix in v12/v13, because those versions don't
have CallStmt.outargs, nor do they do expand_function_arguments
until ExecuteCallStmt runs. We have to duplicatively run
expand_function_arguments, and then re-determine which elements
of the args list are output arguments.
Per bug #18463 from Drew Kimball. Back-patch to all supported
versions, since it's busted in all of them.
Discussion: https://postgr.es/m/18463-f8cd77e12564d8a2@postgresql.org
Presently, when this function is called for an unlogged sequence on
a standby server, it will error out with a message like
ERROR: could not open file "base/5/16388": No such file or directory
Since the pg_sequences system view uses pg_sequence_last_value(),
it can error similarly. To fix, modify the function to return NULL
for unlogged sequences on standby servers. Since this bug is
present on all versions since v15, this approach is preferable to
making the ERROR nicer because we need to repair the pg_sequences
view without modifying its definition on released versions. For
consistency, this commit also modifies the function to return NULL
for other sessions' temporary sequences. The pg_sequences view
already appropriately filters out such sequences, so there's no bug
there, but we might as well offer some defense in case someone
invokes this function directly.
Unlogged sequences were first introduced in v15, but temporary
sequences are much older, so while the fix for unlogged sequences
is only back-patched to v15, the temporary sequence portion is
back-patched to all supported versions.
We could also remove the privilege check in the pg_sequences view
definition in v18 if we modify this function to return NULL for
sequences for which the current user lacks privileges, but that is
left as a future exercise for when v18 development begins.
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/20240501005730.GA594666%40nathanxps13
Backpatch-through: 12
If we recursed to a new call of the same function, with a different
coldeflist (AS clause), it would fail because the inner call would
overwrite the outer call's idea of what to return. This is vaguely
like 1d2fe56e4 and c5bec5426, but it's not due to any API decisions:
it's just that we computed the actual output rowtype at the start of
the call, and saved it in the per-procedure data structure. We can
fix it at basically zero cost by doing the computation at the end
of each call instead of the start.
It's not clear that there's any real-world use-case for such a
function, but given that it doesn't cost anything to fix,
it'd be silly not to.
Per report from Andreas Karlsson. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/1651a46d-3c15-4028-a8c1-d74937b54e19@proxel.se
json_lex_string() relies on pg_encoding_mblen_bounded() to point to the
end of a JSON string when generating an error message, and the input it
uses is not guaranteed to be null-terminated.
It was possible to walk off the end of the input buffer by a few bytes
when the last bytes consist of an incomplete multi-byte sequence, as
token_terminator would point to a location defined by
pg_encoding_mblen_bounded() rather than the end of the input. This
commit switches token_terminator so as the error uses data up to the
end of the JSON input.
More work should be done so as this code could rely on an equivalent of
report_invalid_encoding() so as incorrect byte sequences can show in
error messages in a readable form. This requires work for at least two
cases in the JSON parsing API: an incomplete token and an invalid escape
sequence. A more complete solution may be too invasive for a backpatch,
so this is left as a future improvement, taking care of the overread
first.
A test is added on HEAD as test_json_parser makes this issue
straight-forward to check.
Note that pg_encoding_mblen_bounded() no longer has any callers. This
will be removed on HEAD with a separate commit, as this is proving to
encourage unsafe coding.
Author: Jacob Champion
Discussion: https://postgr.es/m/CAOYmi+ncM7pwLS3AnKCSmoqqtpjvA8wmCdoBtKA3ZrB2hZG6zA@mail.gmail.com
Backpatch-through: 13
If -l was specified together with selective-restore options such as -n
or -N, dependent TOC entries such as comments would be omitted from
the listing, even when an actual restore would have selected them.
This happened because PrintTOCSummary neglected to update the te->reqs
marking of the entry they depended on.
Per report from Justin Pryzby. This has been wrong since 0d4e6ed30
taught _tocEntryRequired to sometimes look at the "reqs" marking of
other TOC entries, so back-patch to all supported branches.
Discussion: https://postgr.es/m/ZjoeirG7yxODdC4P@pryzbyj2023
If a plpython-language trigger caused another one to be invoked,
the "TD" dictionary created for the inner one would overwrite the
outer one's "TD" dictionary. This is more or less the same problem
that 1d2fe56e4 fixed for ordinary functions in plpython, so fix it
the same way, by saving and restoring "TD" during a recursive
invocation.
This fix makes an ABI-incompatible change in struct PLySavedArgs.
I'm not too worried about that because it seems highly unlikely that
any extension is messing with those structs. We could imagine doing
something weird to preserve nominal ABI compatibility in the back
branches, like keeping the saved TD object in an extra element of
namedargs[]. However, that would only be very nominal compatibility:
if anything *is* touching PLySavedArgs, it would likely do the wrong
thing due to not knowing about the additional value. So I judge it
not worth the ugliness to do something different there.
(I also changed struct PLyProcedure, but its added field fits
into formerly-padding space, so that should be safe.)
Per bug #18456 from Jacques Combrink. This bug is very ancient,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/3008982.1714853799@sss.pgh.pa.us
The catalog view pg_stats_ext fails to consider privileges for
expression statistics. The catalog view pg_stats_ext_exprs fails
to consider privileges and row-level security policies. To fix,
restrict the data in these views to table owners or roles that
inherit privileges of the table owner. It may be possible to apply
less restrictive privilege checks in some cases, but that is left
as a future exercise. Furthermore, for pg_stats_ext_exprs, do not
return data for tables with row-level security enabled, as is
already done for pg_stats_ext.
On the back-branches, a fix-CVE-2024-4317.sql script is provided
that will install into the "share" directory. This file can be
used to apply the fix to existing clusters.
Bumps catversion on 'master' branch only.
Reported-by: Lukas Fittl
Reviewed-by: Noah Misch, Tomas Vondra, Tom Lane
Security: CVE-2024-4317
Backpatch-through: 14
The documentation said that you need to pick a suitable LC_COLLATE
setting in addition to setting the DETERMINISTIC flag. This would
have been correct if the libc provider supported nondeterministic
collations, but since it doesn't, you actually need to set the LOCALE
option.
Reviewed-by: Kashif Zeeshan <kashi.zeeshan@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/a71023c2-0ae0-45ad-9688-cf3b93d0d65b%40eisentraut.org
As an optimization, we store "name" columns as cstrings in btree
indexes.
Here we modify it so that Index Only Scans convert these cstrings back
to names with NAMEDATALEN bytes rather than storing the cstring in the
tuple slot, as was happening previously.
Bug: #17855
Reported-by: Alexander Lakhin
Reviewed-by: Alexander Lakhin, Tom Lane
Discussion: https://postgr.es/m/17855-5f523e0f9769a566@postgresql.org
Backpatch-through: 12, all supported versions
We have long disallowed all forms of ALTER TABLE if the table is
already opened by some outer SQL command in the same session.
This has the same purpose as obtaining AccessExclusiveLock, but
since a session's own locks don't conflict the lock only blocks use
of the table by other sessions, not our own. Without this check,
the ALTER might confuse the outer SQL command since any previous
inspection of the table would potentially become invalid.
However, the RelisBecomingView code path in DefineQueryRewrite never
got that memo, and assumed that AccessExclusiveLock is sufficient
for performing something morally equivalent to a rather invasive
ALTER TABLE. Unsurprisingly, this can confuse an outer command
that is trying to do something with the table.
This was submitted as a security issue, but the security team
has been unable to identify any consequence worse than a null
pointer dereference (from trying to access rd_tableam methods
that the relation no longer has). Therefore, in accordance
with our usual policy, it's not security material and should
just be fixed as a routine bug.
Fix by disallowing the operation if the table is open locally,
exactly as ALTER TABLE does it.
Per an anonymous security researcher, via Bundesamt für Sicherheit
in der Informationstechnik.
Patch v12-v15 only. In v16 and later, we removed this code
altogether (cf. commit b23cd185f), so that there's no issue.
vac_update_datfrozenxid() did multiple loads of relfrozenxid and
relminmxid from buffer memory, and it assumed each would get the same
value. Not so if a concurrent vac_update_relstats() did an inplace
update. Commit 2d2e40e3be fixed the same
kind of bug in vac_truncate_clog(). Today's bug could cause the
rel-level field and XIDs in the rel's rows to precede the db-level
field. A cluster having such values should VACUUM affected tables.
Back-patch to v12 (all supported versions).
Discussion: https://postgr.es/m/20240423003956.e7.nmisch@google.com
ALTER COLUMN TYPE wasn't expecting to find any pg_proc objects
depending on the column whose type is to be altered. That indeed
wasn't possible when this code was written, but it is possible
since we introduced new-style SQL function bodies.
It's about as difficult to fix this case as it is to fix dependent
views, and we've been punting on those for years, so I don't feel
too awful about punting for functions too. (I sure wouldn't risk
back-patching such code.) So just throw a more user-facing error.
Also, adjust some of the existing comments to reflect that these
are all pretty much the same issue.
(This patch also fixes it so we will tolerate finding such a
dependency during ALTER COLUMN SET EXPRESSION; in that, we need
not do anything to the function, so no error is wanted. That
problem is new in HEAD.)
Per bug #18449 from Alexander Lakhin. Back-patch to v14 where
we added new-style SQL functions.
Discussion: https://postgr.es/m/18449-f8248467aaa294d5@postgresql.org
In commit 25cd2d640 I (tgl) opined that "The additions of the months
and microseconds fields could also overflow, of course. However,
I believe we need no additional checks there; the existing range
checks should catch such cases". This is demonstrably wrong however
for the microseconds field, and given that discovery it seems prudent
to be paranoid about the months addition as well.
Report and patch by Joseph Koshakow. As before, back-patch to all
supported branches. (However, the test case doesn't work before
v15 because we didn't allow wider-than-int32 numbers in interval
literals. A variant test could probably be built that fits within
that restriction, but it didn't seem worth the trouble.)
Discussion: https://postgr.es/m/CAAvxfHf77sRHKoEzUw9_cMYSpbpNS2C+J_+8Dq4+0oi8iKopeA@mail.gmail.com
The paragraph describing the JavaScript string literals allowed in
jsonpath expressions unnecessarily mentions JSON by erroneously
listing \v as allowed by JSON and mentioning the \xNN and \u{N...}
backslash escapes as deviations from JSON when in fact both are
accepted by ECMAScript/JavaScript. Fix this by only referring to
JavaScript.
Author: Erik Wienhold <ewie@ewie.name>
Discussion: https://www.postgresql.org/message-id/flat/1EB17DF9-2636-484B-9DD0-3CAB19C4F5C4@justatheory.com
This should have the same results for all practical purposes.
The advantage of selecting 'GMT' is that it's guaranteed to work
even when the remote system's timezone database is missing
entries, because pg_tzset() hard-wires handling of that,
at least in 9.2 and later.
(It seems like it would be a good idea to similarly hard-wire
correct handling of 'UTC', but that'll be a little more invasive
than I want to consider back-patching. Leave that for another
day when we're not in feature freeze.)
Per trouble report from Adnan Dautovic. Back-patch to all
supported branches.
Discussion: https://postgr.es/m/465248.1712211585@sss.pgh.pa.us
The documents were clear that queryid should not be assumed to be stable
between major versions but said nothing about minor versions and left
the reader to guess if that was implied by the mention of the
instability of queryid between major versions.
Here we give minor versions an explicit mention to indicate queryid can
generally be assumed stable between minor versions.
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CAApHDvpYGE6h0cD9UO-eHySPynPj1L3J%3DHxT%2BA7Ud8_Yo6AuzA%40mail.gmail.com
Backpatch-through: 12
These operators were removed by 2f70fdb064 in the v14 cycle but they were
accidentally left in the table of build-in operator classes. Backpatch down
to v14 where the operators where removed.
Author: Aleksander Alekseev <aleksander@timescale.com>
Reported-by: Colin Caine <cmcaine@gmail.com>
Discussion: https://postgr.es/m/CADwQTQbbr2UQ_fpbyc+8ay=RwEYgYk=TZxH3+RHDqAQfoG+EWA@mail.gmail.com
Backpatch-through: v14
While back-patching commit 6f0cef935, I forgot that the MSVC
build scripts would also need adjustment in the back branches.
This is a blind attempt at a fix, but it's basically copying
nearby code so I think it will work.
Per buildfarm (via Andrew Dunstan)
Discussion: https://postgr.es/m/4cc4dc47-ca2b-4129-8784-db69b5f82777@dunslane.net
The code associated with EXEC SQL DEFINE was unreadable and full of
bugs, notably:
* It'd attempt to free a non-malloced string if the ecpg program
tries to redefine a macro that was defined on the command line.
* Possible memory stomp if user writes "-D=foo".
* Undef'ing or redefining a macro defined on the command line would
change the state visible to the next file, when multiple files are
specified on the command line. (While possibly that could have been
an intentional choice, the code clearly intends to revert to the
original macro state; it's just failing to consider this interaction.)
* Missing "break" in defining a new macro meant that redefinition
of an existing name would cause an extra entry to be added to the
definition list. While not immediately harmful, a subsequent undef
would result in the prior entry becoming visible again.
* The interactions with input buffering are subtle and were entirely
undocumented.
It's not that surprising that we hadn't noticed these bugs,
because there was no test coverage at all of either the -D
command line switch or multiple input files. This patch adds
such coverage (in a rather hacky way I guess).
In addition to the code bugs, the user documentation was confused
about whether the -D switch defines a C macro or an ecpg one, and
it failed to mention that you can write "-Dsymbol=value".
These problems are old, so back-patch to all supported branches.
Discussion: https://postgr.es/m/998011.1713217712@sss.pgh.pa.us
get_baserel_parampathinfo previously assumed without checking that
the results of generate_join_implied_equalities "necessarily satisfy
join_clause_is_movable_into". This turns out to be wrong in the
presence of outer joins, because the generated clauses could include
Vars that mustn't be evaluated below a relevant outer join. That
led to applying clauses at the wrong plan level and possibly getting
incorrect query results. We must check each clause's nullable_relids,
and really the right thing to do is test join_clause_is_movable_into.
However, trying to fix it that way exposes an oversight in
equivclass.c: it wasn't careful about marking join clauses for
appendrel children with the correct clause_relids. That caused the
modified get_baserel_parampathinfo code to reject some clauses it
still needs to accept. (See parallel commit for HEAD/v16 for more
commentary about that.)
Per bug #18429 from Benoît Ryder. This misbehavior existed for
a long time before commit 2489d76c4, so patch v12-v15 this way.
Discussion: https://postgr.es/m/18429-8982d4a348cc86c6@postgresql.org
Some functions are used in the tree and are currently marked as
deprecated by upstream. This commit refreshes the code to use the
recommended functions, leading to the following changes:
- xmlSubstituteEntitiesDefault() is gone, and needs to be replaced with
XML_PARSE_NOENT for the paths doing the parsing.
- xmlParseMemory() -> xmlReadMemory().
These functions, as well as more functions setting global states, have
been officially marked as deprecated by upstream in August 2022. Their
replacements exist since the 2001-ish area, as far as I have checked,
so that should be safe.
This has been originally applied as 65c5864d7f without a backpatch,
and this has come up as well when working on 400928b83. Per request
from Tom Lane, for new buildfarm member indri that is able to see
deprecation warnings with xmlSubstituteEntitiesDefault() in 16 and older
stable branches.
Author: Dmitry Koval
Discussion: https://postgr.es/m/18274-98d16bc03520665f@postgresql.org
Discussion: https://postgr.es/m/1012981.1713222862@sss.pgh.pa.us
Bakpatch-through: 12
Commit 2ed8f9a01 intended to institute a policy that if a
RangeTblFunction has a coldeflist, then the function return type is
certainly RECORD, and we should use the coldeflist as the source of
truth about what the columns of the record type are. When the
original function has been folded to a constant, inspection of the
constant might give a different answer. This situation will lead to
a tuple-type-mismatch error at execution, but up until that point we
need to consistently believe the coldeflist, or we'll have problems
from different bits of code reaching different conclusions.
expandRTE didn't get that memo though, and would try to produce a
tupdesc based on the constant in this situation, leading to an
assertion failure. (Desultory testing suggests that non-assert
builds often manage to give the expected error, although I also
saw a "cache lookup failed for type 0" error, and it seems at
least possible that a crash could happen.)
Some other callers of get_expr_result_type and get_expr_result_tupdesc
were also being incautious about this. While none of them seem to
have actual bugs, they're working harder than necessary in this case,
besides which it seems safest to have an explicit policy of not using
those functions on an RTE with a coldeflist. Adjust the code
accordingly, and add commentary to funcapi.c about this policy.
Also fix an obsolete comment that claimed "get_expr_result_type()
doesn't know how to extract type info from a RECORD constant".
That hasn't been true since commit d57534740.
Per bug #18422 from Alexander Lakhin.
As with the previous commit, back-patch to all supported branches.
Discussion: https://postgr.es/m/18422-89ca86c8eac5246d@postgresql.org
Properly update the number of bits set in the bitmap after merging the
filters in brin_bloom_union.
This is mostly harmless, as the counter is used only in the output
function, which means pageinspect may show incorrect information about
the BRIN summary. The counter does not affect correctness.
Discovered while adding a regression test comparing indexes built with
and without parallelism. The parallel index builds exercise the union
procedure when merging results from workers, which is otherwise very
hard to do in a test. Which is why this went unnoticed until now.
Backpatch through 14, where the BRIN bloom opclasses were introduced.
Backpatch-through: 14
Discussion: https://postgr.es/m/1df00a66-db5a-4e66-809a-99b386a06d86%40enterprisedb.com
GetPageWithFreeSpace() callers assume the returned block exists in the
main fork, failing with "could not read block" errors if that doesn't
hold. Make that assumption reliable now. It hadn't been guaranteed,
due to the weak WAL and data ordering of participating components. Most
operations on the fsm fork are not WAL-logged. Relation extension is
not WAL-logged. Hence, an fsm-fork block on disk can reference a
main-fork block that no WAL record has initialized. That could happen
after an OS crash, a replica promote, or a PITR restore. wal_log_hints
makes the trouble easier to hit; a replica promote or PITR ending just
after a relevant fsm-fork FPI_FOR_HINT may yield this broken state. The
v16 RelationAddBlocks() mechanism also makes the trouble easier to hit,
since it bulk-extends even without extension lock waiters. Commit
917dc7d239 stopped trouble around
truncation, but vectors involving PageIsNew() pages remained.
This implementation adds a RelationGetNumberOfBlocks() call when the
cached relation size doesn't confirm a block exists. We've been unable
to identify a benchmark that slows materially, but this may show up as
additional time in lseek(). An alternative without that overhead would
be a new ReadBufferMode such that ReadBufferExtended() returns NULL
after a 0-byte read, with all other errors handled normally. However,
each GetFreeIndexPage() caller would then need code for the return-NULL
case. Back-patch to v14, due to earlier versions not caching relation
size and the absence of a pre-v16 problem report.
Ronan Dunklau. Reported by Ronan Dunklau.
Discussion: https://postgr.es/m/1878547.tdWV9SEqCh%40aivenlaptop
This function would have the same issue we solved in commit 501cfd07d:
If an error is thrown after calling CreateWaitEventSet(), the file
descriptor (on epoll- or kqueue-based systems) or handles (on Windows)
that the WaitEventSet contains are leaked.
Like that commit, use PG_TRY-PG_FINALLY (PG_TRY-PG_CATCH in v12) to make
sure the WaitEventSet is freed properly.
Back-patch to all supported versions, but as we do not have this issue
in HEAD (cf. commit 50c67c201), no need to apply this patch to it.
Discussion: https://postgr.es/m/CAPmGK16MqdDoD8oatp8SQWaEa4vS3nfQqDN_Sj9YRuu5J3Lj9g%40mail.gmail.com
Up to now, read_sql_construct() has collected all the source text from
the statement or expression's initial token up to the character just
before the "until" token. It normally tries to strip trailing
whitespace from that, largely for neatness. If there was a "-- text"
comment after the expression, this resulted in removing the newline
that terminates the comment, which creates a hazard if we try to paste
the collected text into a larger SQL construct without inserting a
newline after it. In particular this caused our handling of CASE
constructs to fail if there's a comment after a WHEN expression.
Commit 4adead1d2 noticed a similar problem with cursor arguments,
and worked around it through the rather crude hack of suppressing
the whitespace-trimming behavior for those. Rather than do that
and leave the hazard open for future hackers to trip over, let's
fix it properly. pl_scanner.c already has enough infrastructure
to report the end location of the expression's last token, so
we can copy up to that location and never collect any trailing
whitespace or comment to begin with.
Erik Wienhold and Tom Lane, per report from Michal Bartak.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAAVzF_FjRoi8fOVuLCZhQJx6HATQ7MKm=aFOHWZODFnLmjX-xA@mail.gmail.com
The tools.ietf.org site has been decommissioned and replaced by a
number of sites serving various purposes. Links to RFCs and BCPs
are now 301 redirected to their new respective IETF sites. Since
this serves no purpose and only adds network overhead, update our
links to the new locations.
Backpatch to all supported versions.
Discussion: https://postgr.es/m/3C1CEA99-FCED-447D-9858-5A579B4C6687@yesql.se
Backpatch-through: v12
Tom Lane