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
No configured-by-FDW events would result in "return" directly out of a
PG_TRY block, making the exception stack dangling. Repair.
Oversight in commit 501cfd07d; back-patch to v14, like that commit, but
as we do not have this issue in HEAD (cf. commit 50c67c201), no need to
apply this patch to it.
In passing, improve a comment about the handling of in-process requests
in a postgres_fdw.c function called from this function.
Alexander Pyhalov, with comment adjustment/improvement by me.
Discussion: https://postgr.es/m/425fa29a429b21b0332737c42a4fdc70%40postgrespro.ru
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
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
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
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
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
In commit 272248a0c, we fixed the catalog lookup due to the wrong snapshot
for transactions and subtransactions during decoding. We failed to
consider the case where top-level xact is already marked as containing
catalog change but its subtransaction is not yet marked as containing
catalog change even though it contained such a change.
This can happen when during decoding, none of the WAL records from the
subtransaction was decoded and top-level xact contains a DDL.
We fix it by marking the transaction and all its subtransactions as
containing catalog changes if the top-level xact contains any catalog
change and it is present in the initial running xacts array.
This fix is required only for 14 and 15 because in prior branches we
already always mark the transaction and all its subtransactions as
containing catalog changes in the same case. In 16 and above, we preserve
the list of transaction IDs and sub-transaction IDs, that have modified
catalogs and are running during snapshot serialization, to the serialized
snapshot (see commit 7f13ac8123).
Author: Fei Changhong
Reviewed-by: Amit Kapila, Hayato Kuroda, Andy Fan
Discussion: https://postgr.es/m/18280-4c8060178cb41750@postgresql.org
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
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
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
If an error is thrown after calling CreateWaitEventSet(), the memory
of a WaitEventSet is free'd as it's allocated in the short-lived
memory context, but the file descriptor (on epoll- or kqueue-based
systems) or handles (on Windows) that it contains are leaked.
Use PG_TRY-FINALLY to ensure it gets freed. (On master, I will apply a
better fix, using ResourceOwners to track the WaitEventSet, but that's
not backpatchable.)
The added test doesn't check for leaking resources, so it passed even
before this commit. But at least it covers the code path.
In the passing, fix misleading comment on what the 'nevents' argument
to WaitEventSetWait means.
Report by Alexander Lakhin, analysis and suggestion for the fix by Tom
Lane. Fixes bug #17828. Backpatch to v14 where async execution was
introduced, but master gets a different fix.
Discussion: https://www.postgresql.org/message-id/17828-122da8cba23236be@postgresql.org
Discussion: https://www.postgresql.org/message-id/472235.1678387869@sss.pgh.pa.us
4b8266415 added a precheck to pgrowlocks() to ensure the given object's
pg_class.relam is HEAP_TABLE_AM_OID, however, that check was put before
another check which was checking if the given object was a partitioned
table. Since the pg_class.relam is always InvalidOid for partitioned
tables, if pgrowlocks() was called passing a partitioned table, then the
"only heap AM is supported" error would be raised instead of the intended
error about the given object being a partitioned table.
Here we simply move the pg_class.relam check to after the check that
verifies that we are in fact working with a normal (non-partitioned)
table.
Reported-by: jian he
Discussion: https://postgr.es/m/CACJufxFaSp_WguFCf0X98951zFVX+dXFnF1mxAb-G3g1HiHOow@mail.gmail.com
Backpatch-through: 12, where 4b8266415 was introduced.
pgstatindex failed with ERRCODE_DATA_CORRUPTED, of the "can't-happen"
class XX. The other functions succeeded on an empty index; they might
have malfunctioned if the failed index build left torn I/O or other
complex state. Report an ERROR in statistics functions pgstatindex,
pgstatginindex, pgstathashindex, and pgstattuple. Report DEBUG1 and
skip all index I/O in maintenance functions brin_desummarize_range,
brin_summarize_new_values, brin_summarize_range, and
gin_clean_pending_list. Back-patch to v11 (all supported versions).
Discussion: https://postgr.es/m/20231001195309.a3@google.com
This prevents false-positive reports about "the first child of leftmost
target page is not leftmost of its level", "block %u is not leftmost"
and "left link/right link pair". They appeared if amcheck ran before
VACUUM cleaned things, after a cluster exited recovery between the
first-stage and second-stage WAL records of a deletion. Back-patch to
v11 (all supported versions).
Reviewed by Peter Geoghegan.
Discussion: https://postgr.es/m/20231005025232.c7.nmisch@google.com
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
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
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
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
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
Some of the test_decoding test output was extremely wide, because it
deals with massive toasted values, and the aligned mode causes psql to
produce 200kB of whitespace and dashes. Change to unaligned mode
temporarily to avoid that behavior.
Backpatch to 14, where it applies cleanly.
Discussion: https://postgr.es/m/20230405103953.sxleixp3uz5lazst@alvherre.pgsql
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
The test inserted 70k rows into a foreign table, in order to verify
correct behavior with more than 65535 parameters, and was added in
response to a bug report.
However, this is rather expensive, especially when running the tests
under valgrind, CLOBBER_CACHE_ALWAYS etc. It doesn't seem worth it to
keep running the test, so remove it from all branches (14+).
Backpatch-through: 14
Discussion: https://postgr.es/m/2131017.1623451468@sss.pgh.pa.us
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
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
Non-leaf pages of GiST indexes contain key attributes, leaf pages
contain both key and non-key attributes, and gist_page_items() ignored
the handling of non-key attributes. This caused a few problems when
using gist_page_items() on a GiST index with INCLUDE:
- On a non-leaf page, the function would crash.
- On a leaf page, the function would work, but miss to display all the
values for included attributes.
This commit fixes gist_page_items() to handle such cases in a more
appropriate way, and now displays the values of key and non-key
attributes for each item separately in a style consistent with what
ruleutils.c would generate for the attribute list, depending on the page
type dealt with. In a way similar to how a record is displayed, values
would be double-quoted for key or non-key attributes if required.
ruleutils.c did not provide a routine able to control if non-key
attributes should be displayed, so an extended() routine for index
definitions is added to work around the leaf and non-leaf page
differences.
While on it, this commit fixes a third problem related to the amount of
data reported for key attributes. The code originally relied on
BuildIndexValueDescription() (used for error reports on constraints)
that would not print all the data stored in the index but the index
opclass's input type, so this limited the amount of information
available. This switch makes gist_page_items() much cheaper as there is
no need to run ACL checks for each item printed, which is not an issue
anyway as superuser rights are required to execute the functions of
pageinspect. Opclasses whose data cannot be displayed can rely on
gist_page_items_bytea().
The documentation of this function was slightly incorrect for the
output results generated on HEAD and v15, so adjust it on these
branches.
Author: Alexander Lakhin, Michael Paquier
Discussion: https://postgr.es/m/17884-cb8c326522977acb@postgresql.org
Backpatch-through: 14
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
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
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
The leak would show up when using batch inserts with foreign tables
included in a partition tree, as the slots used in the batch were not
reset once processed. In order to fix this problem, some
ExecClearTuple() are added to clean up the slots used once a batch is
filled and processed, mapping with the number of slots currently in use
as tracked by the counter ri_NumSlots.
This buffer refcount leak has been introduced in b676ac4 with the
addition of the executor facility to improve bulk inserts for FDWs, so
backpatch down to 14.
Alexander has provided the patch (slightly modified by me). The test
for postgres_fdw comes from me, based on the test case that the author
has sent in the report.
Author: Alexander Pyhalov
Discussion: https://postgr.es/m/b035780a740efd38dc30790c76927255@postgrespro.ru
Backpatch-through: 14
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
Commit e88754a196 caused that case
to be reported as corruption, but Peter Geoghegan pointed out that
it can legitimately happen in the case of a speculative insertion
that aborts, so we'd better not flag it as corruption after all.
Back-patch to v14, like the commit that introduced the issue.
Discussion: http://postgr.es/m/CAH2-WzmEabzcPTxSY-NXKH6Qt3FkAPYHGQSe2PtvGgj17ZQkCw@mail.gmail.com
In such cases, get_xid_status() doesn't set its output parameter (the
third argument), so we shouldn't fall through to code which will test
the value of that parameter. There are five existing calls to
get_xid_status(), three of which seem to already handle this case
properly. This commit tries to fix the other two.
If we're checking xmin and find that it is invalid (i.e. 0) just
report that as corruption, similar to what's already done in the
three cases that seem correct. If we're checking xmax and find
that's invalid, that's fine: it just means that the tuple hasn't
been updated or deleted.
Thanks to Andres Freund and valgrind for finding this problem, and
also to Andres for having a look at the patch. This bug seems to go
all the way back to where verify_heapam was first introduced, but
wasn't detected until recently, possibly because of the new test cases
added for update chain verification. Back-patch to v14, where this
code showed up.
Discussion: http://postgr.es/m/CA+TgmoZAYzQZqyUparXy_ks3OEOfLD9-bEXt8N-2tS1qghX9gQ@mail.gmail.com
64bit xids can't represent xids before epoch 0 (see also be504a3e97). When
FullTransactionIdFromXidAndCtx() was passed such an xid, it'd create a 64bit
xid far into the future. Noticed while adding assertions in the course of
investigating be504a3e97, as amcheck's test create such xids.
To fix the issue, just return FirstNormalFullTransactionId in this case. A
freshly initdb'd cluster already has a newer horizon. The most minimal version
of this would make the messages for some detected corruptions differently
inaccurate. To make those cases accurate, switch
FullTransactionIdFromXidAndCtx() to use the 32bit modulo difference between
xid and nextxid to compute the 64bit xid, yielding sensible "in the future" /
"in the past" answers.
Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://postgr.es/m/20230108002923.cyoser3ttmt63bfn@awork3.anarazel.de
Backpatch: 14-, where heapam verification was introduced
The initialization order in update_cached_xid_range() was wrong, calling
FullTransactionIdFromXidAndCtx() before setting
->next_xid. FullTransactionIdFromXidAndCtx() uses ->next_xid.
In most situations this will not cause visible issues, because the next call
to update_cached_xid_range() will use a less wrong ->next_xid. It's rare that
xids advance fast enough for this to be a problem.
Found while adding more asserts to the 64bit xid infrastructure.
Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://postgr.es/m/20230108002923.cyoser3ttmt63bfn@awork3.anarazel.de
Backpatch: 14-, where heapam verification was introduced
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
Attempting to use this function with a raw page not coming from a GiST
index would cause a crash, as it was missing the same sanity checks as
gist_page_items_bytea(). This slightly refactors the code so as all the
basic validation checks for GiST pages are done in a single routine,
in the same fashion as the pageinspect functions for hash and BRIN.
This fixes an issue similar to 076f4d9. A test is added to stress for
this case. While on it, I have added a similar test for
brin_page_items() with a combination make of a valid GiST index and a
raw btree page. This one was already protected, but it was not tested.
Reported-by: Egor Chindyaskin
Author: Dmitry Koval
Discussion: https://postgr.es/m/17815-fc4a2d3b74705703@postgresql.org
Backpatch-through: 14
postgres_fdw will close its remote session if an sinval cache reset
occurs, since it's possible that that means some FDW parameters
changed. We had two tests that were trying to ensure that the
session remains alive by setting debug_discard_caches = 0; but
that's not sufficient. Even though the tests seem stable enough
in the buildfarm, they flap a lot under CI.
In the first test, which is checking the ability to recover from
a lost connection, we can stabilize the results by just not
caring whether pg_terminate_backend() finds a victim backend.
If a reset did happen, there won't be a session to terminate
anymore, but the test can proceed anyway. (Arguably, we are
then not testing the unintentional-disconnect case, but as long
as that scenario is exercised in most runs I think it's fine;
testing the reset-driven case is of value too.)
In the second test, which is trying to verify the application_name
displayed in pg_stat_activity by a remote session, we had a race
condition in that the remote session might go away before we can
fetch its pg_stat_activity entry. We can close that race and make
the test more certainly test what it intends to by arranging things
so that the remote session itself fetches its pg_stat_activity entry
(based on PID rather than a somewhat-circular assumption about the
application name).
Both tests now demonstrably pass under debug_discard_caches = 1,
so we can remove that hack.
Back-patch into relevant back branches.
Discussion: https://postgr.es/m/20230226194340.u44bkfgyz64c67i6@awork3.anarazel.de
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
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
Commit b663a4136, which allowed FDWs to INSERT rows in bulk, added to
nodeModifyTable.c code to flush pending inserts to the foreign-table
result relation(s) before completing processing of the ModifyTable node,
but the code failed to take into account the case where the INSERT query
has modifying CTEs, leading to incorrect results.
Also, that commit failed to flush pending inserts before firing BEFORE
ROW triggers so that rows are visible to such triggers.
In that commit we scanned through EState's
es_tuple_routing_result_relations or es_opened_result_relations list to
find the foreign-table result relations to which pending inserts are
flushed, but that would be inefficient in some cases. So to fix, 1) add
a List member to EState to record the insert-pending result relations,
and 2) modify nodeModifyTable.c so that it adds the foreign-table result
relation to the list in ExecInsert() if appropriate, and flushes pending
inserts properly using the list where needed.
While here, fix a copy-and-pasteo in a comment in ExecBatchInsert(),
which was added by that commit.
Back-patch to v14 where that commit appeared.
Discussion: https://postgr.es/m/CAPmGK16qutyCmyJJzgQOhfBq%3DNoGDqTB6O0QBZTihrbqre%2BoxA%40mail.gmail.com
This reverts commit 5cda142bb9
(in v14 only).
It turns out that that fails under force_parallel_mode = regress,
because pageinspect's disk-access functions are marked parallel
safe, which they are not if you try to use them on a temp table.
The cost of fixing that pre-v15 seems to exceed the value of
making this test case fully stable, so we will just leave things
as-is in v14.
pageinspect has occasionally failed on slow buildfarm members,
with symptoms indicating that the expected effects of VACUUM
FREEZE didn't happen. This is presumably because a background
transaction such as auto-analyze was holding back global xmin.
We can work around that by using a temp table in the test.
Since commit a7212be8b, that will use an up-to-date cutoff xmin
regardless of other processes. And pageinspect itself shouldn't
really care whether the table is temp.
Back-patch to v14. There would be no point in older branches
without back-patching a7212be8b, which seems like more trouble
than the problem is worth.
Discussion: https://postgr.es/m/2892135.1668976646@sss.pgh.pa.us
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
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
Michael Paquier