Commit Graph

3936 Commits

Author SHA1 Message Date
Peter Geoghegan
e493ea866e Count contrib/bloom index scans in pgstat view.
Maintain the pg_stat_user_indexes.idx_scan pgstat counter during
contrib/Bloom index scans.

Oversight in commit 9ee014fc, which added the Bloom index contrib
module.

Author: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Reviewed-By: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/c48839d881388ee401a01807c686004d@oss.nttdata.com
Backpatch: 13- (all supported branches).
2024-11-12 20:57:35 -05:00
Alexander Korotkov
5411e82138 Fix arrays comparison in CompareOpclassOptions()
The current code calls array_eq() and does not provide FmgrInfo.  This commit
provides initialization of FmgrInfo and uses C collation as the safe option
for text comparison because we don't know anything about the semantics of
opclass options.

Backpatch to 13, where opclass options were introduced.

Reported-by: Nicolas Maus
Discussion: https://postgr.es/m/18692-72ea398df3ec6712%40postgresql.org
Backpatch-through: 13
2024-11-12 01:54:38 +02:00
Tom Lane
4310dfa254 Replace usages of xmlXPathCompile() with xmlXPathCtxtCompile().
In existing releases of libxml2, xmlXPathCompile can be driven
to stack overflow because it fails to protect itself against
too-deeply-nested input.  While there is an upstream fix as of
yesterday, it will take years for that to propagate into all
shipping versions.  In the meantime, we can protect our own
usages basically for free by calling xmlXPathCtxtCompile instead.

(The actual bug is that libxml2 keeps its nesting counter in the
xmlXPathContext, and its parsing code was willing to just skip
counting nesting levels if it didn't have a context.  So if we supply
a context, all is well.  It seems odd actually that it works at all
to not supply a context, because this means that XPath parsing does
not have access to XML namespace info.  Apparently libxml2 never
checks namespaces until runtime?  Anyway, this seems like good
future-proofing even if its only immediate effect is to dodge a bug.)

Sadly, this hack only offers protection with libxml2 2.9.11 and newer.
Before that there are multiple similar problems, so if you are
processing untrusted XML it behooves you to get a newer version.
But we have some pretty old libxml2 in the buildfarm, so it seems
impractical to add a regression test to verify this fix.

Per bug #18617 from Jingzhou Fu.  Back-patch to all supported
versions.

Discussion: https://postgr.es/m/18617-1cee4d2ed1f4e7ae@postgresql.org
Discussion: https://gitlab.gnome.org/GNOME/libxml2/-/issues/799
2024-09-15 13:33:09 -04:00
Nathan Bossart
ef46a73f69 Fix contrib/pageinspect's test for sequences.
I managed to break this test in two different ways in commit
05036a3155.

First, the output of the new call to tuple_data_split() on the test
sequence is dependent on endianness.  This is fixed by setting a
special start value for the test sequence that produces the same
output regardless of the endianness of the machine.

Second, on versions older than v15, the new test case fails under
"force_parallel_mode = regress" with the following error:

	ERROR:  cannot access temporary tables during a parallel operation

This is because pageinspect's disk-accessing functions are
incorrectly marked PARALLEL SAFE on versions older than v15 (see
commit aeaaf520f4 for details).  This one is fixed by changing the
test sequence to be permanent.  The only reason it was previously
marked temporary was to avoid needing a DROP SEQUENCE command at
the end of the test.  Unlike some other tests in this file, the use
of a permanent sequence here shouldn't result in any test
instability like what was fixed by commit e2933a6e11.

Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/ZuOKOut5hhDlf_bP%40nathan
Backpatch-through: 12
2024-09-13 10:16:40 -05:00
Nathan Bossart
ca902529cc Reintroduce support for sequences in pgstattuple and pageinspect.
Commit 4b82664156 restricted a number of functions provided by
contrib modules to only relations that use the "heap" table access
method.  Sequences always use this table access method, but they do
not advertise as such in the pg_class system catalog, so the
aforementioned commit also (presumably unintentionally) removed
support for sequences from some of these functions.  This commit
reintroduces said support for sequences to these functions and adds
a couple of relevant tests.

Co-authored-by: Ayush Vatsa
Reviewed-by: Robert Haas, Michael Paquier, Matthias van de Meent
Discussion: https://postgr.es/m/CACX%2BKaP3i%2Bi9tdPLjF5JCHVv93xobEdcd_eB%2B638VDvZ3i%3DcQA%40mail.gmail.com
Backpatch-through: 12
2024-09-12 16:31:29 -05:00
Masahiko Sawada
bbc94abf66 Restrict accesses to non-system views and foreign tables during pg_dump.
When pg_dump retrieves the list of database objects and performs the
data dump, there was possibility that objects are replaced with others
of the same name, such as views, and access them. This vulnerability
could result in code execution with superuser privileges during the
pg_dump process.

This issue can arise when dumping data of sequences, foreign
tables (only 13 or later), or tables registered with a WHERE clause in
the extension configuration table.

To address this, pg_dump now utilizes the newly introduced
restrict_nonsystem_relation_kind GUC parameter to restrict the
accesses to non-system views and foreign tables during the dump
process. This new GUC parameter is added to back branches too, but
these changes do not require cluster recreation.

Back-patch to all supported branches.

Reviewed-by: Noah Misch
Security: CVE-2024-7348
Backpatch-through: 12
2024-08-05 06:05:20 -07:00
Masahiko Sawada
cf2c69ec5a Fix possibility of logical decoding partial transaction changes.
When creating and initializing a logical slot, the restart_lsn is set
to the latest WAL insertion point (or the latest replay point on
standbys). Subsequently, WAL records are decoded from that point to
find the start point for extracting changes in the
DecodingContextFindStartpoint() function. Since the initial
restart_lsn could be in the middle of a transaction, the start point
must be a consistent point where we won't see the data for partial
transactions.

Previously, when not building a full snapshot, serialized snapshots
were restored, and the SnapBuild jumps to the consistent state even
while finding the start point. Consequently, the slot's restart_lsn
and confirmed_flush could be set to the middle of a transaction. This
could lead to various unexpected consequences. Specifically, there
were reports of logical decoding decoding partial transactions, and
assertion failures occurred because only subtransactions were decoded
without decoding their top-level transaction until decoding the commit
record.

To resolve this issue, the changes prevent restoring the serialized
snapshot and jumping to the consistent state while finding the start
point.

On v17 and HEAD, a flag indicating whether snapshot restores should be
skipped has been added to the SnapBuild struct, and SNAPBUILD_VERSION
has been bumpded.

On backbranches, the flag is stored in the LogicalDecodingContext
instead, preserving on-disk compatibility.

Backpatch to all supported versions.

Reported-by: Drew Callahan
Reviewed-by: Amit Kapila, Hayato Kuroda
Discussion: https://postgr.es/m/2444AA15-D21B-4CCE-8052-52C7C2DAFE5C%40amazon.com
Backpatch-through: 12
2024-07-11 22:48:10 +09:00
Heikki Linnakangas
12f327b210 Backport BackgroundPsql perl test module
Backport the new BackgroundPsql modules and the constructor functions,
background_psql() and interactive_psql, to all supported
branches. That makes it easier to backpatch tests that use it.

BackgroundPsql was introduced in version 16. On version 16, this
commit backports just the new timeout argument from master (commit
334f512f45). On older branches, the whole facility. This includes the
change to `use warnings FATAL => 'all'`, which we haven't otherwise
backported, but it seems good to keep the file identical across
branches.

Discussion: https://www.postgresql.org/message-id/b7c64f20-ea01-4f15-9088-0cd6832af149@iki.fi
2024-06-27 19:01:23 +03:00
Etsuro Fujita
2b461efc51 postgres_fdw: Refuse to send FETCH FIRST WITH TIES to remote servers.
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
2024-06-07 17:45:08 +09:00
Tom Lane
0e56b2b944 Make postgres_fdw request remote time zone 'GMT' not 'UTC'.
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
2024-04-21 13:46:20 -04:00
Michael Paquier
bb418aeee2 xml2: Replace deprecated routines with recommended ones
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
2024-04-16 12:26:17 +09:00
Alexander Korotkov
5cc1f26263 amcheck: Normalize index tuples containing uncompressed varlena
It might happen that the varlena value wasn't compressed by index_form_tuple()
due to current storage parameters.  If compression is currently enabled, we
need to compress such values to match index tuple coming from the heap.

Backpatch to all supported versions.

Discussion: https://postgr.es/m/flat/7bdbe559-d61a-4ae4-a6e1-48abdf3024cc%40postgrespro.ru
Author: Andrey Borodin
Reviewed-by: Alexander Lakhin, Michael Zhilin, Jian He, Alexander Korotkov
Backpatch-through: 12
2024-03-23 23:03:12 +02:00
Alexander Korotkov
e2c2414165 amcheck: Support for different header sizes of short varlena datum
In the heap, tuples may contain short varlena datum with both 1B header and 4B
headers.  But the corresponding index tuple should always have such varlena's
with 1B headers.  So, for fingerprinting, we need to convert.

Backpatch to all supported versions.

Discussion: https://postgr.es/m/flat/7bdbe559-d61a-4ae4-a6e1-48abdf3024cc%40postgrespro.ru
Author: Michael Zhilin
Reviewed-by: Alexander Lakhin, Andrey Borodin, Jian He, Alexander Korotkov
Backpatch-through: 12
2024-03-23 23:03:12 +02:00
David Rowley
20b85b3da6 Fix deparsing of Consts in postgres_fdw ORDER BY
For UNION ALL queries where a union child query contained a foreign
table, if the targetlist of that query contained a constant, and the
top-level query performed an ORDER BY which contained the column for the
constant value, then postgres_fdw would find the EquivalenceMember with
the Const and then try to produce an ORDER BY containing that Const.

This caused problems with INT typed Consts as these could appear to be
requests to order by an ordinal column position rather than the constant
value.  This could lead to either an error such as:

ERROR:  ORDER BY position <int const> is not in select list

or worse, if the constant value is a valid column, then we could just
sort by the wrong column altogether.

Here we fix this issue by just not including these Consts in the ORDER
BY clause.

In passing, add a new section for testing ORDER BY in the postgres_fdw
tests and move two existing tests which were misplaced in the WHERE
clause testing section into it.

Reported-by: Michał Kłeczek
Reviewed-by: Ashutosh Bapat, Richard Guo
Bug: #18381
Discussion: https://postgr.es/m/0714C8B8-8D82-4ABB-9F8D-A0C3657E7B6E%40kleczek.org
Discussion: https://postgr.es/m/18381-137456acd168bf93%40postgresql.org
Backpatch-through: 12, oldest supported version
2024-03-11 12:29:03 +13:00
Daniel Gustafsson
375d30bcbb pgcrypto: Fix check for buffer size
The code copying the PGP block into the temp buffer failed to
account for the extra 2 bytes in the buffer which are needed
for the prefix. If the block was oversized, subsequent checks
of the prefix would have exceeded the buffer size.  Since the
block sizes are hardcoded in the list of supported ciphers it
can be verified that there is no live bug here. Backpatch all
the way for consistency though, as this bug is old.

Author: Mikhail Gribkov <youzhick@gmail.com>
Discussion: https://postgr.es/m/CAMEv5_uWvcMCMdRFDsJLz2Q8g16HEa9xWyfrkr+FYMMFJhawOw@mail.gmail.com
Backpatch-through: v12
2024-01-30 11:15:46 +01:00
Tom Lane
7c53b1977b Fix incompatibilities with libxml2 >= 2.12.0.
libxml2 changed the required signature of error handler callbacks
to make the passed xmlError struct "const".  This is causing build
failures on buildfarm member caiman, and no doubt will start showing
up in the field quite soon.  Add a version check to adjust the
declaration of xml_errorHandler() according to LIBXML_VERSION.

2.12.x also produces deprecation warnings for contrib/xml2/xpath.c's
assignment to xmlLoadExtDtdDefaultValue.  I see no good reason for
that to still be there, seeing that we disabled external DTDs (at a
lower level) years ago for security reasons.  Let's just remove it.

Back-patch to all supported branches, since they might all get built
with newer libxml2 once it gets a bit more popular.  (The back
branches produce another deprecation warning about xpath.c's use of
xmlSubstituteEntitiesDefault().  We ought to consider whether to
back-patch all or part of commit 65c5864d7 to silence that.  It's
less urgent though, since it won't break the buildfarm.)

Discussion: https://postgr.es/m/1389505.1706382262@sss.pgh.pa.us
2024-01-29 12:06:08 -05:00
Tom Lane
9e7432fafc Fix integer-overflow problem in intarray's g_int_decompress().
An array element equal to INT_MAX gave this code indigestion,
causing an infinite loop that surely ended in SIGSEGV.  We fixed
some nearby problems awhile ago (cf 757c5182f) but missed this.

Report and diagnosis by Alexander Lakhin (bug #18273); patch by me

Discussion: https://postgr.es/m/18273-9a832d1da122600c@postgresql.org
2024-01-07 15:19:50 -05:00
Michael Paquier
586c6a091f pageinspect: Fix failure with hash_bitmap_info() for partitioned indexes
This function reads directly a page from a relation, relying on
index_open() to open the index to read from.  Unfortunately, this would
crash when using partitioned indexes, as these can be opened with
index_open() but they have no physical pages.

Alexander has fixed the module, while I have written the test.

Author: Alexander Lakhin, Michael Paquier
Discussion: https://postgr.es/m/18246-f4d9ff7cb3af77e6@postgresql.org
Backpatch-through: 12
2023-12-19 18:19:19 +09:00
Michael Paquier
b4c1d255c1 pgstattuple: Fix failure with pgstathashindex() for partitioned indexes
As coded, the function relied on index_open() when opening an index
relation, allowing partitioned indexes to be processed by
pgstathashindex().  This was leading to a "could not open file" error
because partitioned indexes have no physical files, or to a crash with
an assertion failure (like on HEAD).

This issue is fixed by applying the same checks as the other stat
functions for indexes, with a lookup at both RELKIND_INDEX and the index
AM expected.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/18246-f4d9ff7cb3af77e6@postgresql.org
Backpatch-through: 12
2023-12-19 15:20:53 +09:00
David Rowley
b3c8d1d0ea Adjust the order of the prechecks in pgrowlocks()
4b8266415 added a precheck to pgrowlocks() to ensure the given object's
pg_class.relam is HEAP_TABLE_AM_OID, however, that check was put before
another check which was checking if the given object was a partitioned
table.  Since the pg_class.relam is always InvalidOid for partitioned
tables, if pgrowlocks() was called passing a partitioned table, then the
"only heap AM is supported" error would be raised instead of the intended
error about the given object being a partitioned table.

Here we simply move the pg_class.relam check to after the check that
verifies that we are in fact working with a normal (non-partitioned)
table.

Reported-by: jian he
Discussion: https://postgr.es/m/CACJufxFaSp_WguFCf0X98951zFVX+dXFnF1mxAb-G3g1HiHOow@mail.gmail.com
Backpatch-through: 12, where 4b8266415 was introduced.
2023-10-31 16:44:00 +13:00
Noah Misch
123b0d1115 Diagnose !indisvalid in more SQL functions.
pgstatindex failed with ERRCODE_DATA_CORRUPTED, of the "can't-happen"
class XX.  The other functions succeeded on an empty index; they might
have malfunctioned if the failed index build left torn I/O or other
complex state.  Report an ERROR in statistics functions pgstatindex,
pgstatginindex, pgstathashindex, and pgstattuple.  Report DEBUG1 and
skip all index I/O in maintenance functions brin_desummarize_range,
brin_summarize_new_values, brin_summarize_range, and
gin_clean_pending_list.  Back-patch to v11 (all supported versions).

Discussion: https://postgr.es/m/20231001195309.a3@google.com
2023-10-30 14:46:09 -07:00
Noah Misch
f31ccb575e amcheck: Distinguish interrupted page deletion from corruption.
This prevents false-positive reports about "the first child of leftmost
target page is not leftmost of its level", "block %u is not leftmost"
and "left link/right link pair".  They appeared if amcheck ran before
VACUUM cleaned things, after a cluster exited recovery between the
first-stage and second-stage WAL records of a deletion.  Back-patch to
v11 (all supported versions).

Reviewed by Peter Geoghegan.

Discussion: https://postgr.es/m/20231005025232.c7.nmisch@google.com
2023-10-30 14:46:09 -07:00
Dean Rasheed
35e6a5c20d btree_gin: Fix calculation of leftmost interval value.
Formerly, the value computed by leftmostvalue_interval() was a long
way short of the minimum possible interval value.  As a result, an
index scan on a GIN index on an interval column with < or <= operators
would miss large negative interval values.

Fix by setting all fields of the leftmost interval to their minimum
values, ensuring that the result is less than any other possible
interval.  Since this only affects index searches, no index rebuild is
necessary.

Back-patch to all supported branches.

Dean Rasheed, reviewed by Heikki Linnakangas.

Discussion: https://postgr.es/m/CAEZATCV80%2BgOfF8ehNUUfaKBZgZMDfCfL-g1HhWGb6kC3rpDfw%40mail.gmail.com
2023-10-29 11:14:34 +00:00
Noah Misch
6fd1dbdb21 Dissociate btequalimage() from interval_ops, ending its deduplication.
Under interval_ops, some equal values are distinguishable.  One such
pair is '24:00:00' and '1 day'.  With that being so, btequalimage()
breaches the documented contract for the "equalimage" btree support
function.  This can cause incorrect results from index-only scans.
Users should REINDEX any btree indexes having interval-type columns.
After updating, pg_amcheck will report an error for almost all such
indexes.  This fix makes interval_ops simply omit the support function,
like numeric_ops does.  Back-pack to v13, where btequalimage() first
appeared.  In back branches, for the benefit of old catalog content,
btequalimage() code will return false for type "interval".  Going
forward, back-branch initdb will include the catalog change.

Reviewed by Peter Geoghegan.

Discussion: https://postgr.es/m/20231011013317.22.nmisch@google.com
2023-10-14 16:33:54 -07:00
Michael Paquier
a64b8b0355 unaccent: Tweak value of PYTHON when building without Python support
As coded, the module's Makefile would fail to set a value for PYTHON as
it checked if the variable is defined.  When compiling without
--with-python, PYTHON is defined and set to an empty value, so the
existing check is not able to do its work.

This commit switches the rule to check if the value is empty rather than
defined, allowing the generation of unaccent.rules even if --with-python
is not used as long as "python" exists.  BISON and FLEX do the same in
pgxs.mk, for instance.

Thinko in f85a485f89.

Author: Japin Li
Discussion: https://postgr.es/m/MEYP282MB1669F86C0DC7B4DC48489CB0B6C3A@MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM
Backpatch-through: 13
2023-09-27 14:41:26 +09:00
Heikki Linnakangas
db7394d4de Fix another bug in parent page splitting during GiST index build.
Yet another bug in the ilk of commits a7ee7c851 and 741b88435. In
741b88435, we took care to clear the memorized location of the
downlink when we split the parent page, because splitting the parent
page can move the downlink. But we missed that even *updating* a tuple
on the parent can move it, because updating a tuple on a gist page is
implemented as a delete+insert, so the updated tuple gets moved to the
end of the page.

This commit fixes the bug in two different ways (belt and suspenders):

1. Clear the downlink when we update a tuple on the parent page, even
   if it's not split. This the same approach as in commits a7ee7c851
   and 741b88435.

   I also noticed that gistFindCorrectParent did not clear the
   'downlinkoffnum' when it stepped to the right sibling. Fix that
   too, as it seems like a clear bug even though I haven't been able
   to find a test case to hit that.

2. Change gistFindCorrectParent so that it treats 'downlinkoffnum'
   merely as a hint. It now always first checks if the downlink is
   still at that location, and if not, it scans the page like before.
   That's more robust if there are still more cases where we fail to
   clear 'downlinkoffnum' that we haven't yet uncovered. With this,
   it's no longer necessary to meticulously clear 'downlinkoffnum',
   so this makes the previous fixes unnecessary, but I didn't revert
   them because it still seems nice to clear it when we know that the
   downlink has moved.

Also add the test case using the same test data that Alexander
posted. I tried to reduce it to a smaller test, and I also tried to
reproduce this with different test data, but I was not able to, so
let's just include what we have.

Backpatch to v12, like the previous fixes.

Reported-by: Alexander Lakhin
Discussion: https://www.postgresql.org/message-id/18129-caca016eaf0c3702@postgresql.org
2023-09-26 14:15:35 +03:00
Etsuro Fujita
019c13e7a9 postgres_fdw: Fix test for parameterized foreign scan.
Commit e4106b252 should have updated this test, but did not; back-patch
to all supported branches.

Reviewed by Richard Guo.

Discussion: http://postgr.es/m/CAPmGK15nR0NXLSCKQAcqbZbTzrzd5MozowWnTnGfPkayndF43Q%40mail.gmail.com
2023-08-30 17:15:07 +09:00
Etsuro Fujita
730f983eff Disallow replacing joins with scans in problematic cases.
Commit e7cb7ee14, which introduced the infrastructure for FDWs and
custom scan providers to replace joins with scans, failed to add support
handling of pseudoconstant quals assigned to replaced joins in
createplan.c, leading to an incorrect plan without a gating Result node
when postgres_fdw replaced a join with such a qual.

To fix, we could add the support by 1) modifying the ForeignPath and
CustomPath structs to store the list of RestrictInfo nodes to apply to
the join, as in JoinPaths, if they represent foreign and custom scans
replacing a join with a scan, and by 2) modifying create_scan_plan() in
createplan.c to use that list in that case, instead of the
baserestrictinfo list, to get pseudoconstant quals assigned to the join;
but #1 would cause an ABI break.  So fix by modifying the infrastructure
to just disallow replacing joins with such quals.

Back-patch to all supported branches.

Reported by Nishant Sharma.  Patch by me, reviewed by Nishant Sharma and
Richard Guo.

Discussion: https://postgr.es/m/CADrsxdbcN1vejBaf8a%2BQhrZY5PXL-04mCd4GDu6qm6FigDZd6Q%40mail.gmail.com
2023-07-28 15:45:06 +09:00
Tom Lane
7fffcc2ee9 Remove unnecessary pfree() in g_intbig_compress().
GiST compress functions (like all GiST opclass functions) are
supposed to be called in short-lived memory contexts, so that
minor memory leaks in them are not of concern, and indeed
explicit pfree's are likely slightly counterproductive.
But this one in g_intbig_compress() is more than
slightly counterproductive, because it's guarded by
"if (in != DatumGetArrayTypeP(entry->key))" which means
that if this test succeeds, we've detoasted the datum twice.
(And to add insult to injury, the extra detoast result is
leaked.)  Let's just drop the whole stanza, relying on the
GiST temporary context mechanism to clean up in good time.

The analogous bit in g_int_compress() is
       if (r != (ArrayType *) DatumGetPointer(entry->key))
           pfree(r);
which doesn't have the gratuitous-detoast problem so
I left it alone.  Perhaps there is a case for removing
unnecessary pfree's more widely, but I'm not sure if it's
worth the code churn.

The potential extra decompress seems expensive enough to
justify calling this a (minor) performance bug and
back-patching.

Konstantin Knizhnik, Matthias van de Meent, Tom Lane

Discussion: https://postgr.es/m/CAEze2Wi86=DxErfvf+SCB2UKmU2amKOF60BKuJOX=w-RojRn0A@mail.gmail.com
2023-07-13 13:08:28 -04:00
Michael Paquier
ae9aac64a3 intarray: Prevent out-of-bound memory reads with gist__int_ops
As gist__int_ops stands in intarray, it is possible to store GiST
entries for leaf pages that can cause corruptions when decompressed.
Leaf nodes are stored as decompressed all the time by the compression
method, and the decompression method should map with that, retrieving
the contents of the page without doing any decompression.  However, the
code authorized the insertion of leaf page data with a higher number of
array items than what can be supported, generating a NOTICE message to
inform about this matter (199 for a 8k page, for reference).  When
calling the decompression method, a decompression would be attempted on
this leaf node item but the contents should be retrieved as they are.

The NOTICE message generated when dealing with the compression of a leaf
page and too many elements in the input array for gist__int_ops has been
introduced by 08ee64e, removing the marker stored in the array to track
if this is actually a leaf node.  However, it also missed the fact that
the decompression path should do nothing for a leaf page.  Hence, as the
code stand, a too-large array would be stored as uncompressed but the
decompression path would attempt a decompression rather that retrieving
the contents as they are.

This leads to various problems.  First, even if 08ee64e tried to address
that, it is possible to do out-of-bound chunk writes with a large input
array, with the backend informing about that with WARNINGs.  On
decompression, retrieving the stored leaf data would lead to incorrect
memory reads, leading to crashes or even worse.

Perhaps somebody would be interested in expanding the number of array
items that can be handled in a leaf page for this operator in the
future, which would require revisiting the choice done in 08ee64e, but
based on the lack of reports about this problem since 2005 it does not
look so.  For now, this commit prevents the insertion of data for leaf
pages when using more array items that the code can handle on
decompression, switching the NOTICE message to an ERROR.  If one wishes
to use more array items, gist__intbig_ops is an optional choice.

While on it, use ERRCODE_PROGRAM_LIMIT_EXCEEDED as error code when a
limit is reached, because that's what the module is facing in such
cases.

Author: Ankit Kumar Pandey, Alexander Lakhin
Reviewed-by: Richard Guo, Michael Paquier
Discussion: https://postgr.es/m/796b65c3-57b7-bddf-b0d5-a8afafb8b627@gmail.com
Discussion: https://postgr.es/m/17888-f72930e6b5ce8c14@postgresql.org
Backpatch-through: 11
2023-06-15 13:45:41 +09:00
Michael Paquier
78bf0a256d hstore: Tighten key/value parsing check for whitespaces
isspace() can be locale-sensitive depending on the platform, causing
hstore to consider as whitespaces characters it should not see as such.
For example, U+0105, being decoded as 0xC4 0x85 in UTF-8, would be
discarded from the input given.

This problem is similar to 9ae2661, though it was missed that hstore
can also manipulate non-ASCII inputs, so replace the existing isspace()
calls with scanner_isspace().

This problem exists for a long time, so backpatch all the way down.

Author: Evan Jones
Discussion: https://postgr.es/m/CA+HWA9awUW0+RV_gO9r1ABZwGoZxPztcJxPy8vMFSTbTfi4jig@mail.gmail.com
Backpatch-through: 11
2023-06-12 09:14:17 +09:00
Tom Lane
0409c7fc74 Ensure Soundex difference() function handles empty input sanely.
fuzzystrmatch's difference() function assumes that _soundex()
always initializes its output buffer fully.  This was not so for
the case of a string containing no alphabetic characters, resulting
in unstable output and Valgrind complaints.

Fix by using memset() to fill the whole buffer in the early-exit
case.  Also make some cosmetic improvements (I didn't care for the
random switches between "instr[0]" and "*instr" notation).

Report and diagnosis by Alexander Lakhin (bug #17935).
Back-patch to all supported branches.

Discussion: https://postgr.es/m/17935-b99316aa79c18513@postgresql.org
2023-05-16 10:53:42 -04:00
Tom Lane
feb9e7fbbc Adjust sepgsql expected output for 681d9e462 et al.
Security: CVE-2023-2454
2023-05-08 11:24:47 -04:00
Noah Misch
2212f7db80 Replace last PushOverrideSearchPath() call with set_config_option().
The two methods don't cooperate, so set_config_option("search_path",
...) has been ineffective under non-empty overrideStack.  This defect
enabled an attacker having database-level CREATE privilege to execute
arbitrary code as the bootstrap superuser.  While that particular attack
requires v13+ for the trusted extension attribute, other attacks are
feasible in all supported versions.

Standardize on the combination of NewGUCNestLevel() and
set_config_option("search_path", ...).  It is newer than
PushOverrideSearchPath(), more-prevalent, and has no known
disadvantages.  The "override" mechanism remains for now, for
compatibility with out-of-tree code.  Users should update such code,
which likely suffers from the same sort of vulnerability closed here.
Back-patch to v11 (all supported versions).

Alexander Lakhin.  Reported by Alexander Lakhin.

Security: CVE-2023-2454
2023-05-08 06:14:12 -07:00
Tom Lane
de2dfa0538 In hstore_plpython, avoid crashing when return value isn't a mapping.
Python 3 changed the behavior of PyMapping_Check(), breaking the
test in plpython_to_hstore() that verifies whether a function result
to be transformed is acceptable.  A backwards-compatible fix is to
first verify that the object doesn't pass PySequence_Check().

Perhaps accidentally, our other uses of PyMapping_Check() already
follow uses of PySequence_Check(), so that no other bugs were
created by this change.

Per bug #17908 from Alexander Lakhin.  Back-patch to all supported
branches.

Dmitry Dolgov and Tom Lane

Discussion: https://postgr.es/m/17908-3f19a125d56a11d6@postgresql.org
2023-04-27 11:55:06 -04:00
Alexander Korotkov
48c6825d0e Validate ltree siglen GiST option to be int-aligned
Unaligned siglen could lead to an unaligned access to subsequent key fields.

Backpatch to 13, where opclass options were introduced.

Reported-by:  Alexander Lakhin
Bug: 17847
Discussion: https://postgr.es/m/17847-171232970bea406b%40postgresql.org
Reviewed-by: Tom Lane, Pavel Borisov, Alexander Lakhin
Backpatch-through: 13
2023-04-23 14:00:16 +03:00
Tom Lane
bc436e4a91 Fix misbehavior in contrib/pg_trgm with an unsatisfiable regex.
If the regex compiler can see that a regex is unsatisfiable
(for example, '$foo') then it may emit an NFA having no arcs.
pg_trgm's packGraph function did the wrong thing in this case;
it would access off the end of a work array, and with bad luck
could produce a corrupted output data structure causing more
problems later.  This could end with wrong answers or crashes
in queries using a pg_trgm GIN or GiST index with such a regex.

Fix by not trying to de-duplicate if there aren't at least 2 arcs.

Per bug #17830 from Alexander Lakhin.  Back-patch to all supported
branches.

Discussion: https://postgr.es/m/17830-57ff5f89bdb02b09@postgresql.org
2023-03-11 12:15:41 -05:00
Tom Lane
ad38e2f891 Fix calculation of which GENERATED columns need to be updated.
We were identifying the updatable generated columns of inheritance
children by transposing the calculation made for their parent.
However, there's nothing that says a traditional-inheritance child
can't have generated columns that aren't there in its parent, or that
have different dependencies than are in the parent's expression.
(At present it seems that we don't enforce that for partitioning
either, which is likely wrong to some degree or other; but the case
clearly needs to be handled with traditional inheritance.)

Hence, drop the very-klugy-anyway "extraUpdatedCols" RTE field
in favor of identifying which generated columns depend on updated
columns during executor startup.  In HEAD we can remove
extraUpdatedCols altogether; in back branches, it's still there but
always empty.  Another difference between the HEAD and back-branch
versions of this patch is that in HEAD we can add the new bitmap field
to ResultRelInfo, but that would cause an ABI break in back branches.
Like 4b3e37993, add a List field at the end of struct EState instead.

Back-patch to v13.  The bogus calculation is also being made in v12,
but it doesn't have the same visible effect because we don't use it
to decide which generated columns to recalculate; as a consequence of
which the patch doesn't apply easily.  I think that there might still
be a demonstrable bug associated with trigger firing conditions, but
that's such a weird corner-case usage that I'm content to leave it
unfixed in v12.

Amit Langote and Tom Lane

Discussion: https://postgr.es/m/CA+HiwqFshLKNvQUd1DgwJ-7tsTp=dwv7KZqXC4j2wYBV1aCDUA@mail.gmail.com
Discussion: https://postgr.es/m/2793383.1672944799@sss.pgh.pa.us
2023-01-05 14:12:17 -05:00
Tom Lane
d35f1d485c Fix contrib/seg to be more wary of long input numbers.
seg stores the number of significant digits in an input number
in a "char" field.  If char is signed, and the input is more than
127 digits long, the count can read out as negative causing
seg_out() to print garbage (or, if you're really unlucky,
even crash).

To fix, clamp the digit count to be not more than FLT_DIG.
(In theory this loses some information about what the original
input was, but it doesn't seem like useful information; it would
not survive dump/restore in any case.)

Also, in case there are stored values of the seg type containing
bad data, add a clamp in seg_out's restore() subroutine.

Per bug #17725 from Robins Tharakan.  It's been like this
forever, so back-patch to all supported branches.

Discussion: https://postgr.es/m/17725-0a09313b67fbe86e@postgresql.org
2022-12-21 17:51:50 -05:00
Tom Lane
9a299cf7c2 Replace RelationOpenSmgr() with RelationGetSmgr().
This is a back-patch of the v15-era commit f10f0ae42 into older
supported branches.  The idea is to design out bugs in which an
ill-timed relcache flush clears rel->rd_smgr partway through
some code sequence that wasn't expecting that.  We had another
report today of a corner case that reliably crashes v14 under
debug_discard_caches (nee CLOBBER_CACHE_ALWAYS), and therefore
would crash once in a blue moon in the field.  We're unlikely
to get rid of all such code paths unless we adopt the more
rigorous coding rules instituted by f10f0ae42.  Therefore,
even though this is a bit invasive, it's time to back-patch.
Some comfort can be taken in the fact that f10f0ae42 has been
in v15 for 16 months without problems.

I left the RelationOpenSmgr macro present in the back branches,
even though no core code should use it anymore, in order to not break
third-party extensions in minor releases.  Such extensions might opt
to start using RelationGetSmgr instead, to reduce their code
differential between v15 and earlier branches.  This carries a hazard
of failing to compile against headers from existing minor releases.
However, once compiled the extension should work fine even with such
releases, because RelationGetSmgr is a "static inline" function so
it creates no link-time dependency.  So depending on distribution
practices, that might be an OK tradeoff.

Per report from Spyridon Dimitrios Agathos.  Original patch
by Amul Sul.

Discussion: https://postgr.es/m/CAFM5RaqdgyusQvmWkyPYaWMwoK5gigdtW-7HcgHgOeAw7mqJ_Q@mail.gmail.com
Discussion: https://postgr.es/m/CANiYTQsU7yMFpQYnv=BrcRVqK_3U3mtAzAsJCaqtzsDHfsUbdQ@mail.gmail.com
2022-11-17 16:54:30 -05:00
Michael Paquier
c304c069d1 Fix compilation warnings with libselinux 3.1 in contrib/sepgsql/
Upstream SELinux has recently marked security_context_t as officially
deprecated, causing warnings with -Wdeprecated-declarations.  This is
considered as legacy code for some time now by upstream as
security_context_t got removed from most of the code tree during the
development of 2.3 back in 2014.

This removes all the references to security_context_t in sepgsql/ to be
consistent with SELinux, fixing the warnings.  Note that this does not
impact the minimum version of libselinux supported.

This has been applied first as 1f32136 for 14~, but no other branches
got the call.  This is in line with the recent project policy to have no
warnings in branches where builds should still be supported (9.2~ as of
today).  Per discussion with Tom Lane and Álvaro Herrera.

Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20200813012735.GC11663@paquier.xyz
Discussion: https://postgr.es/m/20221103181028.raqta27jcuypor4l@alvherre.pgsql
Backpatch-through: 9.2
2022-11-09 09:39:53 +09:00
Tom Lane
a9fdb48b73 pg_stat_statements: fetch stmt location/length before it disappears.
When executing a utility statement, we must fetch everything
we need out of the PlannedStmt data structure before calling
standard_ProcessUtility.  In certain cases (possibly only ROLLBACK
in extended query protocol), that data structure will get freed
during command execution.  The situation is probably often harmless
in production builds, but in debug builds we intentionally overwrite
the freed memory with garbage, leading to picking up garbage values
of statement location and length, typically causing an assertion
failure later in pg_stat_statements.  In non-debug builds, if
something did go wrong it would likely lead to storing garbage
for the query string.

Report and fix by zhaoqigui (with cosmetic adjustments by me).
It's an old problem, so back-patch to all supported versions.

Discussion: https://postgr.es/m/17663-a344fd0675f92128@postgresql.org
Discussion: https://postgr.es/m/1667307420050.56657@hundsun.com
2022-11-01 12:48:01 -04:00
Amit Kapila
25f7be1ca2 Fix assertion failures while processing NEW_CID record in logical decoding.
When the logical decoding restarts from NEW_CID, since there is no
association between the top transaction and its subtransaction, both are
created as top transactions and have the same LSN. This caused the
assertion failure in AssertTXNLsnOrder().

This patch skips the assertion check until we reach the LSN at which we
start decoding the contents of the transaction, specifically
start_decoding_at LSN in SnapBuild. This is okay because we don't
guarantee to make the association between top transaction and
subtransaction until we try to decode the actual contents of transaction.
The ordering of the records prior to the start_decoding_at LSN should have
been checked before the restart.

The other assertion failure is due to the reason that we forgot to track
that we have considered top-level transaction id in the list of catalog
changing transactions that were committed when one of its subtransactions
is marked as containing catalog change.

Reported-by: Tomas Vondra, Osumi Takamichi
Author: Masahiko Sawada, Kuroda Hayato
Reviewed-by: Amit Kapila, Dilip Kumar, Kuroda Hayato, Kyotaro Horiguchi, Masahiko Sawada
Backpatch-through: 10
Discussion: https://postgr.es/m/a89b46b6-0239-2fd5-71a9-b19b1f7a7145%40enterprisedb.com
Discussion: https://postgr.es/m/TYCPR01MB83733C6CEAE47D0280814D5AED7A9%40TYCPR01MB8373.jpnprd01.prod.outlook.com
2022-10-20 09:25:13 +05:30
Etsuro Fujita
6749d4e8c7 postgres_fdw: Avoid 'variable not found in subplan target list' error.
The tlist of the EvalPlanQual outer plan for a ForeignScan node is
adjusted to produce a tuple whose descriptor matches the scan tuple slot
for the ForeignScan node.  But in the case where the outer plan contains
an extra Sort node, if the new tlist contained columns required only for
evaluating PlaceHolderVars or columns required only for evaluating local
conditions, this would cause setrefs.c to fail with the error.

The cause of this is that when creating the outer plan by injecting the
Sort node into an alternative local join plan that could emit such extra
columns as well, we fail to arrange for the outer plan to propagate them
up through the Sort node, causing setrefs.c to fail to match up them in
the new tlist to what is available from the outer plan.  Repair.

Per report from Alexander Pyhalov.

Richard Guo and Etsuro Fujita, reviewed by Alexander Pyhalov and Tom Lane.
Backpatch to all supported versions.

Discussion: http://postgr.es/m/cfb17bf6dfdf876467bd5ef533852d18%40postgrespro.ru
2022-09-14 18:45:04 +09:00
Tom Lane
a61095aa79 Reject bogus output from uuid_create(3).
When using the BSD UUID functions, contrib/uuid-ossp expects
uuid_create() to produce a version-1 UUID.  FreeBSD still does so,
but in recent NetBSD releases that function produces a version-4
(random) UUID instead.  That's not acceptable for our purposes:
if the user wanted v4 she would have asked for v4, not v1.
Hence, check the version digit and complain if it's not '1'.

Also drop the documentation's claim that the NetBSD implementation
is usable.  It might be, depending on which OS version you're using,
but we're not going to get into that kind of detail.

(Maybe someday we should ditch all these external libraries
and just write our own UUID code, but today is not that day.)

Nazir Bilal Yavuz, with cosmetic adjustments and docs by me.
Backpatch to all supported versions.

Discussion: https://postgr.es/m/3848059.1661038772@sss.pgh.pa.us
Discussion: https://postgr.es/m/17358-89806e7420797025@postgresql.org
2022-09-09 12:41:36 -04:00
Amit Kapila
547b963683 Fix catalog lookup with the wrong snapshot during logical decoding.
Previously, we relied on HEAP2_NEW_CID records and XACT_INVALIDATION
records to know if the transaction has modified the catalog, and that
information is not serialized to snapshot. Therefore, after the restart,
if the logical decoding decodes only the commit record of the transaction
that has actually modified a catalog, we will miss adding its XID to the
snapshot. Thus, we will end up looking at catalogs with the wrong
snapshot.

To fix this problem, this changes the snapshot builder so that it
remembers the last-running-xacts list of the decoded RUNNING_XACTS record
after restoring the previously serialized snapshot. Then, we mark the
transaction as containing catalog changes if it's in the list of initial
running transactions and its commit record has XACT_XINFO_HAS_INVALS. To
avoid ABI breakage, we store the array of the initial running transactions
in the static variables InitialRunningXacts and NInitialRunningXacts,
instead of storing those in SnapBuild or ReorderBuffer.

This approach has a false positive; we could end up adding the transaction
that didn't change catalog to the snapshot since we cannot distinguish
whether the transaction has catalog changes only by checking the COMMIT
record. It doesn't have the information on which (sub) transaction has
catalog changes, and XACT_XINFO_HAS_INVALS doesn't necessarily indicate
that the transaction has catalog change. But that won't be a problem since
we use snapshot built during decoding only to read system catalogs.

On the master branch, we took a more future-proof approach by writing
catalog modifying transactions to the serialized snapshot which avoids the
above false positive. But we cannot backpatch it because of a change in
the SnapBuild.

Reported-by: Mike Oh
Author: Masahiko Sawada
Reviewed-by: Amit Kapila, Shi yu, Takamichi Osumi, Kyotaro Horiguchi, Bertrand Drouvot, Ahsan Hadi
Backpatch-through: 10
Discussion: https://postgr.es/m/81D0D8B0-E7C4-4999-B616-1E5004DBDCD2%40amazon.com
2022-08-11 09:30:55 +05:30
Tom Lane
6b67db10c3 Be more wary about 32-bit integer overflow in pg_stat_statements.
We've heard a couple of reports of people having trouble with
multi-gigabyte-sized query-texts files.  It occurred to me that on
32-bit platforms, there could be an issue with integer overflow
of calculations associated with the total query text size.
Address that with several changes:

1. Limit pg_stat_statements.max to INT_MAX / 2 not INT_MAX.
The hashtable code will bound it to that anyway unless "long"
is 64 bits.  We still need overflow guards on its use, but
this helps.

2. Add a check to prevent extending the query-texts file to
more than MaxAllocHugeSize.  If it got that big, qtext_load_file
would certainly fail, so there's not much point in allowing it.
Without this, we'd need to consider whether extent, query_offset,
and related variables shouldn't be off_t not size_t.

3. Adjust the comparisons in need_gc_qtexts() to be done in 64-bit
arithmetic on all platforms.  It appears possible that under duress
those multiplications could overflow 32 bits, yielding a false
conclusion that we need to garbage-collect the texts file, which
could lead to repeatedly garbage-collecting after every hash table
insertion.

Per report from Bruno da Silva.  I'm not convinced that these
issues fully explain his problem; there may be some other bug that's
contributing to the query-texts file becoming so large in the first
place.  But it did get that big, so #2 is a reasonable defense,
and #3 could explain the reported performance difficulties.

(See also commit 8bbe4cbd9, which addressed some related bugs.
The second Discussion: link is the thread that led up to that.)

This issue is old, and is primarily a problem for old platforms,
so back-patch.

Discussion: https://postgr.es/m/CAB+Nuk93fL1Q9eLOCotvLP07g7RAv4vbdrkm0cVQohDVMpAb9A@mail.gmail.com
Discussion: https://postgr.es/m/5601D354.5000703@BlueTreble.com
2022-08-02 18:05:34 -04:00
Tom Lane
6230bd7df4 postgres_fdw: set search_path to 'pg_catalog' while deparsing constants.
The motivation for this is to ensure successful transmission of the
values of constants of regconfig and other reg* types.  The remote
will be reading them with search_path = 'pg_catalog', so schema
qualification is necessary when referencing objects in other schemas.

Per bug #17483 from Emmanuel Quincerot.  Back-patch to all supported
versions.  (There's some other stuff to do here, but it's less
back-patchable.)

Discussion: https://postgr.es/m/1423433.1652722406@sss.pgh.pa.us
2022-07-17 17:27:50 -04:00
Noah Misch
8782ce49e4 CREATE INDEX: use the original userid for more ACL checks.
Commit a117cebd63 used the original userid
for ACL checks located directly in DefineIndex(), but it still adopted
the table owner userid for more ACL checks than intended.  That broke
dump/reload of indexes that refer to an operator class, collation, or
exclusion operator in a schema other than "public" or "pg_catalog".
Back-patch to v10 (all supported versions), like the earlier commit.

Nathan Bossart and Noah Misch

Discussion: https://postgr.es/m/f8a4105f076544c180a87ef0c4822352@stmuk.bayern.de
2022-06-25 09:07:45 -07:00
Tom Lane
60ca2e8418 Silence compiler warnings from some older compilers.
Since a117cebd6, some older gcc versions issue "variable may be used
uninitialized in this function" complaints for brin_summarize_range.
Silence that using the same coding pattern as in bt_index_check_internal;
arguably, a117cebd6 had too narrow a view of which compilers might give
trouble.

Nathan Bossart and Tom Lane.  Back-patch as the previous commit was.

Discussion: https://postgr.es/m/20220601163537.GA2331988@nathanxps13
2022-06-01 17:21:45 -04:00