Commit Graph

48525 Commits

Author SHA1 Message Date
Thomas Munro b9ed85698f Revert "Fix race in Parallel Hash Join batch cleanup."
This reverts commit 8fa2478b40.

Discussion: https://postgr.es/m/CA%2BhUKGJmcqAE3MZeDCLLXa62cWM0AJbKmp2JrJYaJ86bz36LFA%40mail.gmail.com
2021-03-18 01:06:01 +13:00
Thomas Munro 8fa2478b40 Fix race in Parallel Hash Join batch cleanup.
With very unlucky timing and parallel_leader_participation off, PHJ
could attempt to access per-batch state just as it was being freed.
There was code intended to prevent that by checking for a cleared
pointer, but it was buggy.

Fix, by introducing an extra barrier phase.  The new phase
PHJ_BUILD_RUNNING means that it's safe to access the per-batch state to
find a batch to help with, and PHJ_BUILD_DONE means that it is too late.
The last to detach will free the array of per-batch state as before, but
now it will also atomically advance the phase at the same time, so that
late attachers can avoid the hazard, without the data race.  This
mirrors the way per-batch hash tables are freed (see phases
PHJ_BATCH_PROBING and PHJ_BATCH_DONE).

Revealed by a one-off build farm failure, where BarrierAttach() failed a
sanity check assertion, because the memory had been clobbered by
dsa_free().

Back-patch to 11, where the code arrived.

Reported-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/20200929061142.GA29096%40paquier.xyz
2021-03-17 18:09:03 +13:00
Tom Lane 6e34755560 Avoid corner-case memory leak in SSL parameter processing.
After reading the root cert list from the ssl_ca_file, immediately
install it as client CA list of the new SSL context.  That gives the
SSL context ownership of the list, so that SSL_CTX_free will free it.
This avoids a permanent memory leak if we fail further down in
be_tls_init(), which could happen if bogus CRL data is offered.

The leak could only amount to something if the CRL parameters get
broken after server start (else we'd just quit) and then the server
is SIGHUP'd many times without fixing the CRL data.  That's rather
unlikely perhaps, but it seems worth fixing, if only because the
code is clearer this way.

While we're here, add some comments about the memory management
aspects of this logic.

Noted by Jelte Fennema and independently by Andres Freund.
Back-patch to v10; before commit de41869b6 it doesn't matter,
since we'd not re-execute this code during SIGHUP.

Discussion: https://postgr.es/m/16160-18367e56e9a28264@postgresql.org
2021-03-16 16:02:49 -04:00
Tom Lane 60e5c2b143 Fix race condition in psql \e's detection of file modification.
psql's editing commands decide whether the user has edited the file
by checking for change of modification timestamp.  This is probably
fine for a pre-existing file, but with a temporary file that is
created within the command, it's possible for a fast typist to
save-and-exit in less than the one-second granularity of stat(2)
timestamps.  On Windows FAT filesystems the granularity is even
worse, 2 seconds, making the race a bit easier to hit.

To fix, try to set the temp file's mod time to be two seconds ago.
It's unlikely this would fail, but then again the race condition
itself is unlikely, so just ignore any error.

Also, we might as well check the file size as well as its mod time.

While this is a difficult bug to hit, it still seems worth
back-patching, to ensure that users' edits aren't lost.

Laurenz Albe, per gripe from Jacob Champion; based on fix suggestions
from Jacob and myself

Discussion: https://postgr.es/m/0ba3f2a658bac6546d9934ab6ba63a805d46a49b.camel@cybertec.at
2021-03-12 12:20:15 -05:00
Tom Lane e7f7950f67 Forbid marking an identity column as nullable.
GENERATED ALWAYS AS IDENTITY implies NOT NULL, but the code failed
to complain if you overrode that with "GENERATED ALWAYS AS IDENTITY
NULL".  One might think the old behavior was a feature, but it was
inconsistent because the outcome varied depending on the order of
the clauses, so it seems to have been just an oversight.

Per bug #16913 from Pavel Boev.  Back-patch to v10 where identity
columns were introduced.

Vik Fearing (minor tweaks by me)

Discussion: https://postgr.es/m/16913-3b5198410f67d8c6@postgresql.org
2021-03-12 11:08:42 -05:00
Peter Geoghegan ce54c024d9 Restore vacuum_cleanup_index_scale_factor coverage.
Revert two recent commits that had btree_index.sql drop regression test
indexes rather than leave them behind for pg_dump testing.

This is intended to restore pg_upgrade coverage of indexes with the
vacuum_cleanup_index_scale_factor storage parameter set on buildfarm
member crake.

Backpatch: 11-12 only
2021-03-11 12:52:37 -08:00
Tom Lane 56defbdd0f Re-simplify management of inStart in pqParseInput3's subroutines.
Commit 92785dac2 copied some logic related to advancement of inStart
from pqParseInput3 into getRowDescriptions and getAnotherTuple,
because it wanted to allow user-defined row processor callbacks to
potentially longjmp out of the library, and inStart would have to be
updated before that happened to avoid an infinite loop.  We later
decided that that API was impossibly fragile and reverted it, but
we didn't undo all of the related code changes, and this bit of
messiness survived.  Undo it now so that there's just one place in
pqParseInput3's processing where inStart is advanced; this will
simplify addition of better tracing support.

getParamDescriptions had grown similar processing somewhere along
the way (not in 92785dac2; I didn't track down just when), but it's
actually buggy because its handling of corrupt-message cases seems to
have been copied from the v2 logic where we lacked a known message
length.  The cases where we "goto not_enough_data" should not simply
return EOF, because then we won't consume the message, potentially
creating an infinite loop.  That situation now represents a
definitively corrupt message, and we should report it as such.

Although no field reports of getParamDescriptions getting stuck in
a loop have been seen, it seems appropriate to back-patch that fix.
I chose to back-patch all of this to keep the logic looking more alike
in supported branches.

Discussion: https://postgr.es/m/2217283.1615411989@sss.pgh.pa.us
2021-03-11 14:43:45 -05:00
Peter Geoghegan 1cc33ab95c Drop other index behind pg_upgrade test issue.
Fix the test failure by dropping the index in question.  Missed by
commit 57ae7885.

Per buildfarm member crake.

Backpatch: 11-12 only
2021-03-10 23:32:58 -08:00
Peter Geoghegan 57ae7885cf Drop index behind pg_upgrade test issue.
The vacuum_cleanup_index_scale_factor storage parameter was set in a
btree index that was previously left behind in the regression test
database.  As a result, the index gets tested within pg_dump and
pg_restore tests, as well as pg_upgrade testing.  This won't work when
upgrading to Postgres 14, though, because the storage parameter was
removed on that version by commit 9f3665fb.

Fix the test failure by dropping the index in question.

Per buildfarm member crake.

Discussion: https://postgr.es/m/CAH2-WzmeXYBWdhF7BMhNjhq9exsk=E1ohqBFAwzPdXJZ1XDMUA@mail.gmail.com
Backpatch: 11-12 only
2021-03-10 19:00:48 -08:00
Bruce Momjian 5645a6af70 tutorial: land height is "elevation", not "altitude"
This is a follow-on patch to 92c12e46d5.  In that patch, we renamed
"altitude" to "elevation" in the docs, based on these details:

   https://mapscaping.com/blogs/geo-candy/what-is-the-difference-between-elevation-relief-and-altitude

This renames the tutorial SQL files to match the documentation.

Reported-by: max1@inbox.ru

Discussion: https://postgr.es/m/161512392887.1046.3137472627109459518@wrigleys.postgresql.org

Backpatch-through: 9.6
2021-03-10 20:25:18 -05:00
Tom Lane 74207b8fc5 Doc: improve introductory information about procedures.
Clarify the discussion in "User-Defined Procedures", by laying out
the key differences between functions and procedures in a bulleted
list.  Notably, this avoids burying the lede about procedures being
able to do transaction control.  Make the back-link in the CREATE
FUNCTION reference page more prominent, and add one in CREATE
PROCEDURE.

Per gripe from Guyren Howe.  Thanks to David Johnston for discussion.

Discussion: https://postgr.es/m/BYAPR03MB4903C53A8BB7EFF5EA289674A6949@BYAPR03MB4903.namprd03.prod.outlook.com
2021-03-10 11:33:50 -05:00
Tom Lane 8fff8a8749 Validate the OID argument of pg_import_system_collations().
"SELECT pg_import_system_collations(0)" caused an assertion failure.
With a random nonzero argument --- or indeed with zero, in non-assert
builds --- it would happily make pg_collation entries with garbage
values of collnamespace.  These are harmless as far as I can tell
(unless maybe the OID happens to become used for a schema, later on?).
In any case this isn't a security issue, since the function is
superuser-only.  But it seems like a gotcha for unwary DBAs, so let's
add a check that the given OID belongs to some schema.

Back-patch to v10 where this function was introduced.
2021-03-08 18:21:51 -05:00
Amit Kapila c267ca6828 Clarify the usage of max_replication_slots on the subscriber side.
It was not clear in the docs that the max_replication_slots is also used
to track replication origins on the subscriber side.

Author: Paul Martinez
Reviewed-by: Amit Kapila
Backpatch-through: 10 where logical replication was introduced
Discussion: https://postgr.es/m/CACqFVBZgwCN_pHnW6dMNCrOS7tiHCw6Retf_=U2Vvj3aUSeATw@mail.gmail.com
2021-03-03 10:30:27 +05:30
Alvaro Herrera f927767919
Use native path separators to pg_ctl in initdb
On Windows, CMD.EXE allegedly does not run a command that uses forward slashes,
so let's convert the path to use backslashes instead.

Backpatch to 10.

Author: Nitin Jadhav <nitinjadhavpostgres@gmail.com>
Reviewed-by: Juan José Santamaría Flecha <juanjo.santamaria@gmail.com>
Discussion: https://postgr.es/m/CAMm1aWaNDuaPYFYMAqDeJrZmPtNvLcJRS++CcZWY8LT6KcoBZw@mail.gmail.com
2021-03-02 15:39:34 -03:00
Michael Paquier 0f1b0c0b60 Fix duplicated test case in TAP tests of reindexdb
The same test for REINDEX (VERBOSE) was done twice, while it is clear
that the second test should use --concurrently.  Issue introduced in
5dc92b8, for what looks like a copy-paste mistake.

Reviewed-by: Mark Dilger
Discussion: https://postgr.es/m/A7AE97EA-F4B0-4CAB-8FFF-3FECD31F9D63@enterprisedb.com
Backpatch-through: 12
2021-03-02 13:19:11 +09:00
Alvaro Herrera 262eb990c7
Fix use-after-free bug with AfterTriggersTableData.storeslot
AfterTriggerSaveEvent() wrongly allocates the slot in execution-span
memory context, whereas the correct thing is to allocate it in
a transaction-span context, because that's where the enclosing
AfterTriggersTableData instance belongs into.

Backpatch to 12 (the test back to 11, where it works well with no code
changes, and it's good to have to confirm that the case was previously
well supported); this bug seems introduced by commit ff11e7f4b9.

Reported-by: Bertrand Drouvot <bdrouvot@amazon.com>
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/39a71864-b120-5a5c-8cc5-c632b6f16761@amazon.com
2021-02-27 18:09:15 -03:00
Tom Lane fb1e218cb0 Doc: further clarify libpq's description of connection string URIs.
Break the synopsis into named parts to make it less confusing.
Make more than zero effort at applying SGML markup.  Do a bit
of copy-editing of nearby text.

The synopsis revision is by Alvaro Herrera and Paul Förster,
the rest is my fault.  Back-patch to v10 where multi-host
connection strings appeared.

Discussion: https://postgr.es/m/6E752D6B-487C-463E-B6E2-C32E7FB007EA@gmail.com
2021-02-26 15:24:01 -05:00
Michael Paquier 9e9b5c0501 doc: Mention PGDATABASE as supported by pgbench
PGHOST, PGPORT and PGUSER were already mentioned, but not PGDATABASE.
Like 5aaa584, backpatch down to 12.

Reported-by: Christophe Courtois
Discussion: https://postgr.es/m/161399398648.21711.15387267201764682579@wrigleys.postgresql.org
Backpatch-through: 12
2021-02-25 16:07:08 +09:00
Michael Paquier 3b2af88788 Fix some typos, grammar and style in docs and comments
The portions fixing the documentation are backpatched where needed.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20210210235557.GQ20012@telsasoft.com
backpatch-through: 9.6
2021-02-24 16:14:00 +09:00
Alvaro Herrera 2796ae2ad2
Reinstate HEAP_XMAX_LOCK_ONLY|HEAP_KEYS_UPDATED as allowed
Commit 866e24d47d added an assert that HEAP_XMAX_LOCK_ONLY and
HEAP_KEYS_UPDATED cannot appear together, on the faulty assumption that
the latter necessarily referred to an update and not a tuple lock; but
that's wrong, because SELECT FOR UPDATE can use precisely that
combination, as evidenced by the amcheck test case added here.

Remove the Assert(), and also patch amcheck's verify_heapam.c to not
complain if the combination is found.  Also, out of overabundance of
caution, update (across all branches) README.tuplock to be more explicit
about this.

Author: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Mahendra Singh Thalor <mahi6run@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Discussion: https://postgr.es/m/20210124061758.GA11756@nol
2021-02-23 17:30:21 -03:00
Fujii Masao 67b3ee2929 Fix psql's ON_ERROR_ROLLBACK so that it handles COMMIT AND CHAIN.
When ON_ERROR_ROLLBACK is enabled, psql releases a temporary savepoint
if it's idle in a valid transaction block after executing a query. But psql
doesn't do that after RELEASE or ROLLBACK is executed because a temporary
savepoint has already been destroyed in that case.

This commit changes psql's ON_ERROR_ROLLBACK so that it doesn't release
a temporary savepoint also when COMMIT AND CHAIN is executed. A temporary
savepoint doesn't need to be released in that case because
COMMIT AND CHAIN also destroys any savepoints defined within the transaction
to commit. Otherwise psql tries to release the savepoint that
COMMIT AND CHAIN has already destroyed and cause an error
"ERROR:  savepoint "pg_psql_temporary_savepoint" does not exist".

Back-patch to v12 where transaction chaining was added.

Reported-by: Arthur Nascimento
Author: Arthur Nascimento
Reviewed-by: Fujii Masao, Vik Fearing
Discussion: https://postgr.es/m/16867-3475744069228158@postgresql.org
2021-02-19 22:02:44 +09:00
Fujii Masao fadcc4e81b Fix bug in COMMIT AND CHAIN command.
This commit fixes COMMIT AND CHAIN command so that it starts new transaction
immediately even if savepoints are defined within the transaction to commit.
Previously COMMIT AND CHAIN command did not in that case because
commit 280a408b48 forgot to make CommitTransactionCommand() handle
a transaction chaining when the transaction state was TBLOCK_SUBCOMMIT.

Also this commit adds the regression test for COMMIT AND CHAIN command
when savepoints are defined.

Back-patch to v12 where transaction chaining was added.

Reported-by: Arthur Nascimento
Author: Fujii Masao
Reviewed-by: Arthur Nascimento, Vik Fearing
Discussion: https://postgr.es/m/16867-3475744069228158@postgresql.org
2021-02-19 21:59:26 +09:00
Tom Lane e7cddb5f29 Fix another ancient bug in parsing of BRE-mode regular expressions.
While poking at the regex code, I happened to notice that the bug
squashed in commit afcc8772e had a sibling: next() failed to return
a specific value associated with the '}' token for a "\{m,n\}"
quantifier when parsing in basic RE mode.  Again, this could result
in treating the quantifier as non-greedy, which it never should be in
basic mode.  For that to happen, the last character before "\}" that
sets "nextvalue" would have to set it to zero, or it'd have to have
accidentally been zero from the start.  The failure can be provoked
repeatably with, for example, a bound ending in digit "0".

Like the previous patch, back-patch all the way.
2021-02-18 22:38:55 -05:00
Magnus Hagander 6a31b48ec8 Fix typo
Author: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/0CF087FC-BEAD-4010-8BB9-3CDD74DC9060@yesql.se
2021-02-17 13:56:10 +01:00
Heikki Linnakangas 2b81444a88 Make ExecGetInsertedCols() and friends more robust and improve comments.
If ExecGetInsertedCols(), ExecGetUpdatedCols() or ExecGetExtraUpdatedCols()
were called with a ResultRelInfo that's not in the range table and isn't a
partition routing target, the functions would dereference a NULL pointer,
relinfo->ri_RootResultRelInfo. Such ResultRelInfos are created when firing
RI triggers in tables that are not modified directly. None of the current
callers of these functions pass such relations, so this isn't a live bug,
but let's make them more robust.

Also update comment in ResultRelInfo; after commit 6214e2b228,
ri_RangeTableIndex is zero for ResultRelInfos created for partition tuple
routing.

Noted by Coverity. Backpatch down to v11, like commit 6214e2b228.

Reviewed-by: Tom Lane, Amit Langote
2021-02-15 09:29:45 +02:00
Thomas Munro a27f3a7f41 Default to wal_sync_method=fdatasync on FreeBSD.
FreeBSD 13 gained O_DSYNC, which would normally cause wal_sync_method to
choose open_datasync as its default value.  That may not be a good
choice for all systems, and performs worse than fdatasync in some
scenarios.  Let's preserve the existing default behavior for now.

Like commit 576477e73c, which did the same for Linux, back-patch to all
supported releases.

Discussion: https://postgr.es/m/CA%2BhUKGLsAMXBQrCxCXoW-JsUYmdOL8ALYvaX%3DCrHqWxm-nWbGA%40mail.gmail.com
2021-02-15 16:06:18 +13:00
Thomas Munro 840eda04eb Hold interrupts while running dsm_detach() callbacks.
While cleaning up after a parallel query or parallel index creation that
created temporary files, we could be interrupted by a statement timeout.
The error handling path would then fail to clean up the files when it
ran dsm_detach() again, because the callback was already popped off the
list.  Prevent this hazard by holding interrupts while the cleanup code
runs.

Thanks to Heikki Linnakangas for this suggestion, and also to Kyotaro
Horiguchi, Masahiko Sawada, Justin Pryzby and Tom Lane for discussion of
this and earlier ideas on how to fix the problem.

Back-patch to all supported releases.

Reported-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/20191212180506.GR2082@telsasoft.com
2021-02-15 14:20:52 +13:00
Tom Lane c3dc311ffd pg_attribute_no_sanitize_alignment() macro
Modern gcc and clang compilers offer alignment sanitizers, which help to detect
pointer misalignment.  However, our codebase already contains x86-specific
crc32 computation code, which uses unalignment access.  Thankfully, those
compilers also support the attribute, which disables alignment sanitizers at
the function level.  This commit adds pg_attribute_no_sanitize_alignment(),
which wraps this attribute, and applies it to pg_comp_crc32c_sse42() function.

Back-patch of commits 993bdb9f9 and ad2ad698a, to enable doing
alignment testing in all supported branches.

Discussion: https://postgr.es/m/CAPpHfdsne3%3DT%3DfMNU45PtxdhSL_J2PjLTeS8rwKnJzUR4YNd4w%40mail.gmail.com
Discussion: https://postgr.es/m/475514.1612745257%40sss.pgh.pa.us
Author: Alexander Korotkov, revised by Tom Lane
Reviewed-by: Tom Lane
2021-02-13 17:49:08 -05:00
Tom Lane 0347470b31 Avoid divide-by-zero in regex_selectivity() with long fixed prefix.
Given a regex pattern with a very long fixed prefix (approaching 500
characters), the result of pow(FIXED_CHAR_SEL, fixed_prefix_len) can
underflow to zero.  Typically the preceding selectivity calculation
would have underflowed as well, so that we compute 0/0 and get NaN.
In released branches this leads to an assertion failure later on.
That doesn't happen in HEAD, for reasons I've not explored yet,
but it's surely still a bug.

To fix, just skip the division when the pow() result is zero, so
that we'll (most likely) return a zero selectivity estimate.  In
the edge cases where "sel" didn't yet underflow, perhaps this
isn't desirable, but I'm not sure that the case is worth spending
a lot of effort on.  The results of regex_selectivity_sub() are
barely worth the electrons they're written on anyway :-(

Per report from Alexander Lakhin.  Back-patch to all supported versions.

Discussion: https://postgr.es/m/6de0a0c3-ada9-cd0c-3e4e-2fa9964b41e3@gmail.com
2021-02-12 16:26:47 -05:00
Michael Paquier 5b2945ec0a Fix ORDER BY clause in new regression test of REINDEX CONCURRENTLY
Oversight in bd12080.

Reported-by: Justin Pryzby
Discussion: https://postgr.es/m/20210210065805.GG20012@telsasoft.com
Backpatch-through: 12
2021-02-10 16:59:43 +09:00
Michael Paquier 85edb1f261 Preserve pg_attribute.attstattarget across REINDEX CONCURRENTLY
For an index, attstattarget can be updated using ALTER INDEX SET
STATISTICS.  This data was lost on the new index after REINDEX
CONCURRENTLY.

The update of this field is done when the old and new indexes are
swapped to make the fix back-patchable.  Another approach we could look
after in the long-term is to change index_create() to pass the wanted
values of attstattarget when creating the new relation, but, as this
would cause an ABI breakage this can be done only on HEAD.

Reported-by: Ronan Dunklau
Author: Michael Paquier
Reviewed-by: Ronan Dunklau, Tomas Vondra
Discussion: https://postgr.es/m/16628084.uLZWGnKmhe@laptop-ronand
Backpatch-through: 12
2021-02-10 13:09:12 +09:00
Tom Lane 1b9eb7cde7 Stamp 12.6. 2021-02-08 16:56:03 -05:00
Peter Eisentraut 73844356cf Translation updates
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: 08f1c10dca3d7b8efc365107c737b87c1c3a82ee
2021-02-08 17:50:22 +01:00
Tom Lane 392c530d10 Last-minute updates for release notes.
Security: CVE-2021-3393, CVE-2021-20229
2021-02-08 11:10:40 -05:00
Heikki Linnakangas f50e888990 Fix permission checks on constraint violation errors on partitions.
If a cross-partition UPDATE violates a constraint on the target partition,
and the columns in the new partition are in different physical order than
in the parent, the error message can reveal columns that the user does not
have SELECT permission on. A similar bug was fixed earlier in commit
804b6b6db4.

The cause of the bug is that the callers of the
ExecBuildSlotValueDescription() function got confused when constructing
the list of modified columns. If the tuple was routed from a parent, we
converted the tuple to the parent's format, but the list of modified
columns was grabbed directly from the child's RTE entry.

ExecUpdateLockMode() had a similar issue. That lead to confusion on which
columns are key columns, leading to wrong tuple lock being taken on tables
referenced by foreign keys, when a row is updated with INSERT ON CONFLICT
UPDATE. A new isolation test is added for that corner case.

With this patch, the ri_RangeTableIndex field is no longer set for
partitions that don't have an entry in the range table. Previously, it was
set to the RTE entry of the parent relation, but that was confusing.

NOTE: This modifies the ResultRelInfo struct, replacing the
ri_PartitionRoot field with ri_RootResultRelInfo. That's a bit risky to
backpatch, because it breaks any extensions accessing the field. The
change that ri_RangeTableIndex is not set for partitions could potentially
break extensions, too. The ResultRelInfos are visible to FDWs at least,
and this patch required small changes to postgres_fdw. Nevertheless, this
seem like the least bad option. I don't think these fields widely used in
extensions; I don't think there are FDWs out there that uses the FDW
"direct update" API, other than postgres_fdw. If there is, you will get a
compilation error, so hopefully it is caught quickly.

Backpatch to 11, where support for both cross-partition UPDATEs, and unique
indexes on partitioned tables, were added.

Reviewed-by: Amit Langote
Security: CVE-2021-3393
2021-02-08 11:01:55 +02:00
Tom Lane e474abdadd Release notes for 13.2, 12.6, 11.11, 10.16, 9.6.21, 9.5.25. 2021-02-07 15:46:38 -05:00
Tom Lane 46f2971135 Revert "Propagate CTE property flags when copying a CTE list into a rule."
This reverts commit ed29089633 and
equivalent back-branch commits.  The issue is subtler than I thought,
and it's far from new, so just before a release deadline is no time
to be fooling with it.  We'll consider what to do at a bit more
leisure.

Discussion: https://postgr.es/m/CAJcOf-fAdj=nDKMsRhQzndm-O13NY4dL6xGcEvdX5Xvbbi0V7g@mail.gmail.com
2021-02-07 12:54:08 -05:00
Tom Lane 2a7664a79c Propagate CTE property flags when copying a CTE list into a rule.
rewriteRuleAction() neglected this step, although it was careful to
propagate other similar flags such as hasSubLinks or hasRowSecurity.
Omitting to transfer hasRecursive is just cosmetic at the moment,
but omitting hasModifyingCTE is a live bug, since the executor
certainly looks at that.

The proposed test case only fails back to v10, but since the executor
examines hasModifyingCTE in 9.x as well, I suspect that a test case
could be devised that fails in older branches.  Given the nearness
of the release deadline, though, I'm not going to spend time looking
for a better test.

Report and patch by Greg Nancarrow, cosmetic changes by me

Discussion: https://postgr.es/m/CAJcOf-fAdj=nDKMsRhQzndm-O13NY4dL6xGcEvdX5Xvbbi0V7g@mail.gmail.com
2021-02-06 19:28:39 -05:00
Tom Lane f733219570 Disallow converting an inheritance child table to a view.
Generally, members of inheritance trees must be plain tables (or,
in more recent versions, foreign tables).  ALTER TABLE INHERIT
rejects creating an inheritance relationship that has a view at
either end.  When DefineQueryRewrite attempts to convert a relation
to a view, it already had checks prohibiting doing so for partitioning
parents or children as well as traditional-inheritance parents ...
but it neglected to check that a traditional-inheritance child wasn't
being converted.  Since the planner assumes that any inheritance
child is a table, this led to making plans that tried to do a physical
scan on a view, causing failures (or even crashes, in recent versions).

One could imagine trying to support such a case by expanding the view
normally, but since the rewriter runs before the planner does
inheritance expansion, it would take some very fundamental refactoring
to make that possible.  There are probably a lot of other parts of the
system that don't cope well with such a situation, too.  For now,
just forbid it.

Per bug #16856 from Yang Lin.  Back-patch to all supported branches.
(In versions before v10, this includes back-patching the portion of
commit 501ed02cf that added has_superclass().  Perhaps the lack of
that infrastructure partially explains the missing check.)

Discussion: https://postgr.es/m/16856-0363e05c6e1612fd@postgresql.org
2021-02-06 15:17:01 -05:00
Heikki Linnakangas 9b0ce89579 Fix backslash-escaping multibyte chars in COPY FROM.
If a multi-byte character is escaped with a backslash in TEXT mode input,
and the encoding is one of the client-only encodings where the bytes after
the first one can have an ASCII byte "embedded" in the char, we didn't
skip the character correctly. After a backslash, we only skipped the first
byte of the next character, so if it was a multi-byte character, we would
try to process its second byte as if it was a separate character. If it
was one of the characters with special meaning, like '\n', '\r', or
another '\\', that would cause trouble.

One such exmple is the byte sequence '\x5ca45c2e666f6f' in Big5 encoding.
That's supposed to be [backslash][two-byte character][.][f][o][o], but
because the second byte of the two-byte character is 0x5c, we incorrectly
treat it as another backslash. And because the next character is a dot, we
parse it as end-of-copy marker, and throw an "end-of-copy marker corrupt"
error.

Backpatch to all supported versions.

Reviewed-by: John Naylor, Kyotaro Horiguchi
Discussion: https://www.postgresql.org/message-id/a897f84f-8dca-8798-3139-07da5bb38728%40iki.fi
2021-02-05 11:16:33 +02:00
Tom Lane 77e760d5cc Avoid crash when rolling back within a prepared statement.
If a portal is used to run a prepared CALL or DO statement that
contains a ROLLBACK, PortalRunMulti fails because the portal's
statement list gets cleared by the rollback.  (Since the grammar
doesn't allow CALL/DO in PREPARE, the only easy way to get to this is
via extended query protocol, which treats all inputs as prepared
statements.)  It's difficult to avoid resetting the portal early
because of resource-management issues, so work around this by teaching
PortalRunMulti to be wary of portal->stmts having suddenly become NIL.

The crash has only been seen to occur in v13 and HEAD (as a
consequence of commit 1cff1b95a having added an extra touch of
portal->stmts).  But even before that, the code involved touching a
List that the portal no longer has any claim on.  In the test case at
hand, the List will still exist because of another refcount on the
cached plan; but I'm far from convinced that it's impossible for the
cached plan to have been dropped by the time control gets back to
PortalRunMulti.  Hence, backpatch to v11 where nested transactions
were added.

Thomas Munro and Tom Lane, per bug #16811 from James Inform

Discussion: https://postgr.es/m/16811-c1b599b2c6c2d622@postgresql.org
2021-02-03 19:38:29 -05:00
Peter Eisentraut 1dd6baf788 pg_dump: Fix dumping of inherited generated columns
Generation expressions of generated columns are always inherited, so
there is no need to set them separately in child tables, and there is
no syntax to do so either.  The code previously used the code paths
for the handling of default values, for which different rules apply;
in particular it might want to set a default value explicitly for an
inherited column.  This resulted in unrestorable dumps.  For generated
columns, just skip them in inherited tables.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/15830.1575468847%40sss.pgh.pa.us
2021-02-03 11:58:15 +01:00
Tom Lane 78fab84338 Remove extra increment of plpgsql's statement counter for FOR loops.
This left gaps in the internal statement numbering, which is not
terribly harmful (else we'd have noticed sooner), but it's not
great either.

Oversight in bbd5c207b; backpatch to v12 where that came in.

Pavel Stehule

Discussion: https://postgr.es/m/CAFj8pRDXyQaJmpotNTQVc-t-WxdWZC35V2PnmwOaV1-taidFWA@mail.gmail.com
2021-02-02 14:35:25 -05:00
Tom Lane 7428469586 Fix ancient memory leak in contrib/auto_explain.
The ExecutorEnd hook is invoked in a context that could be quite
long-lived, not the executor's own per-query context as I think
we were sort of assuming.  Thus, any cruft generated while producing
the EXPLAIN output could accumulate over multiple queries.  This can
result in spectacular leakage if log_nested_statements is on, and
even without that I'm surprised nobody complained before.

To fix, just switch into the executor's context so that anything we
allocate will be released when standard_ExecutorEnd frees the executor
state.  We might as well nuke the code's retail pfree of the explain
output string, too; that's laughably inadequate to the need.

Japin Li, per report from Jeff Janes.  This bug is old, so
back-patch to all supported branches.

Discussion: https://postgr.es/m/CAMkU=1wCVtbeRn0s9gt12KwQ7PLXovbpM8eg25SYocKW3BT4hg@mail.gmail.com
2021-02-02 13:49:08 -05:00
Noah Misch be843ce297 Fix CREATE INDEX CONCURRENTLY for simultaneous prepared transactions.
In a cluster having used CREATE INDEX CONCURRENTLY while having enabled
prepared transactions, queries that use the resulting index can silently
fail to find rows.  Fix this for future CREATE INDEX CONCURRENTLY by
making it wait for prepared transactions like it waits for ordinary
transactions.  This expands the VirtualTransactionId structure domain to
admit prepared transactions.  It may be necessary to reindex to recover
from past occurrences.  Back-patch to 9.5 (all supported versions).

Andrey Borodin, reviewed (in earlier versions) by Tom Lane and Michael
Paquier.

Discussion: https://postgr.es/m/2E712143-97F7-4890-B470-4A35142ABC82@yandex-team.ru
2021-01-30 00:01:56 -08:00
Alexander Korotkov bd6366129b Document behavior of the .** jsonpath accessor in the lax mode
When the .** jsonpath accessor handles the array, it selects both array and
each of its elements.  When using lax mode, subsequent accessors automatically
unwrap arrays.  So, the content of each array element may be selected twice.

Even though this behavior is counterintuitive, it's correct because everything
works as designed.  This commit documents it.

Backpatch to 12 where the jsonpath language was introduced.

Reported-by: Thomas Kellerer
Bug: #16828
Discussion: https://postgr.es/m/16828-2b0229babfad2d8c%40postgresql.org
Discussion: https://postgr.es/m/CAPpHfdtS-nNidT%3DEqZbAYOPcnNOWh_sd6skVdu2CAQUGdvpT8Q%40mail.gmail.com
Author: Alexandex Korotkov, revised by Tom Lane
Reviewed-by: Alvaro Herrera, Thomas Kellerer, Tom Lane
Backpatch-through: 12
2021-01-29 15:28:16 +03:00
Tom Lane 22f71a6e1d Silence another gcc 11 warning.
Per buildfarm and local experimentation, bleeding-edge gcc isn't
convinced that the MemSet in reorder_function_arguments() is safe.
Shut it up by adding an explicit check that pronargs isn't negative,
and by changing MemSet to memset.  (It appears that either change is
enough to quiet the warning at -O2, but let's do both to be sure.)
2021-01-28 17:18:34 -05:00
Tom Lane 7c53a80675 Fix hash partition pruning with asymmetric partition sets.
perform_pruning_combine_step() was not taught about the number of
partition indexes used in hash partitioning; more embarrassingly,
get_matching_hash_bounds() also had it wrong.  These errors are masked
in the common case where all the partitions have the same modulus
and no partition is missing.  However, with missing or unequal-size
partitions, we could erroneously prune some partitions that need
to be scanned, leading to silently wrong query answers.

While a minimal-footprint fix for this could be to export
get_partition_bound_num_indexes and make the incorrect functions use it,
I'm of the opinion that that function should never have existed in the
first place.  It's not reasonable data structure design that
PartitionBoundInfoData lacks any explicit record of the length of
its indexes[] array.  Perhaps that was all right when it could always
be assumed equal to ndatums, but something should have been done about
it as soon as that stopped being true.  Putting in an explicit
"nindexes" field makes both partition_bounds_equal() and
partition_bounds_copy() simpler, safer, and faster than before,
and removes explicit knowledge of the number-of-partition-indexes
rules from some other places too.

This change also makes get_hash_partition_greatest_modulus obsolete.
I left that in place in case any external code uses it, but no core
code does anymore.

Per bug #16840 from Michał Albrycht.  Back-patch to v11 where the
hash partitioning code came in.  (In the back branches, add the new
field at the end of PartitionBoundInfoData to minimize ABI risks.)

Discussion: https://postgr.es/m/16840-571a22976f829ad4@postgresql.org
2021-01-28 13:41:55 -05:00
Tom Lane 25f9a72662 Make ecpg's rjulmdy() and rmdyjul() agree with their declarations.
We had "short *mdy" in the extern declarations, but "short mdy[3]"
in the actual function definitions.  Per C99 these are equivalent,
but recent versions of gcc have started to issue warnings about
the inconsistency.  Clean it up before the warnings get any more
widespread.

Back-patch, in case anyone wants to build older PG versions with
bleeding-edge compilers.

Discussion: https://postgr.es/m/2401575.1611764534@sss.pgh.pa.us
2021-01-28 11:17:33 -05:00
Alvaro Herrera 30854d94c6
pgbench: Remove dead code
doConnect() never returns connections in state CONNECTION_BAD, so
checking for that is pointless.  Remove the code that does.

This code has been dead since ba708ea3dc, 20 years ago.

Discussion: https://postgr.es/m/20210126195224.GA20361@alvherre.pgsql
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
2021-01-28 12:50:40 -03:00