Commit Graph

21522 Commits

Author SHA1 Message Date
Andres Freund e6d77f22c7 Fix corruption due to vacuum_defer_cleanup_age underflowing 64bit xids
When vacuum_defer_cleanup_age is bigger than the current xid, including the
epoch, the subtraction of vacuum_defer_cleanup_age would lead to a wrapped
around xid. While that normally is not a problem, the subsequent conversion to
a 64bit xid results in a 64bit-xid very far into the future. As that xid is
used as a horizon to detect whether rows versions are old enough to be
removed, that allows removal of rows that are still visible (i.e. corruption).

If vacuum_defer_cleanup_age was never changed from the default, there is no
chance of this bug occurring.

This bug was introduced in dc7420c2c9.  A lesser version of it exists in
12-13, introduced by fb5344c969, affecting only GiST.

The 12-13 version of the issue can, in rare cases, lead to pages in a gist
index getting recycled too early, potentially causing index entries to be
found multiple times.

The fix is fairly simple - don't allow vacuum_defer_cleanup_age to retreat
further than FirstNormalTransactionId.

Patches to make similar bugs easier to find, by adding asserts to the 64bit
xid infrastructure, have been proposed, but are not suitable for backpatching.

Currently there are no tests for vacuum_defer_cleanup_age. A patch introducing
infrastructure to make writing a test easier has been posted to the list.

Reported-by: Michail Nikolaev <michail.nikolaev@gmail.com>
Reviewed-by: Matthias van de Meent <boekewurm+postgres@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20230108002923.cyoser3ttmt63bfn@awork3.anarazel.de
Backpatch: 12-, but impact/fix is smaller for 12-13
2023-03-07 21:36:51 -08:00
Tom Lane 695b34ab35 Fix more bugs caused by adding columns to the end of a view.
If a view is defined atop another view, and then CREATE OR REPLACE
VIEW is used to add columns to the lower view, then when the upper
view's referencing RTE is expanded by ApplyRetrieveRule we will have
a subquery RTE with fewer eref->colnames than output columns.  This
confuses various code that assumes those lists are always in sync,
as they are in plain parser output.

We have seen such problems before (cf commit d5b760ecb), and now
I think the time has come to do what was speculated about in that
commit: let's make ApplyRetrieveRule synthesize some column names to
preserve the invariant that holds in parser output.  Otherwise we'll
be chasing this class of bugs indefinitely.  Moreover, it appears from
testing that this actually gives us better results in the test case
d5b760ecb added, and likely in other corner cases that we lack
coverage for.

In HEAD, I replaced d5b760ecb's hack to make expandRTE exit early with
an elog(ERROR) call, since the case is now presumably unreachable.
But it seems like changing that in back branches would bring more risk
than benefit, so there I just updated the comment.

Per bug #17811 from Alexander Lakhin.  Back-patch to all supported
branches.

Discussion: https://postgr.es/m/17811-d31686b78f0dffc9@postgresql.org
2023-03-07 18:21:37 -05:00
Tom Lane 4a94cbd02b Fix some more cases of missed GENERATED-column updates.
If UPDATE is forced to retry after an EvalPlanQual check, it neglected
to repeat GENERATED-column computations, even though those might well
have changed since we're dealing with a different tuple than before.
Fixing this is mostly a matter of looping back a bit further when
we retry.  In v15 and HEAD that's most easily done by altering the API
of ExecUpdateAct so that it includes computing GENERATED expressions.

Also, if an UPDATE in a partitioned table turns into a cross-partition
INSERT operation, we failed to recompute GENERATED columns.  That's a
bug since 8bf6ec3ba allowed partitions to have different generation
expressions; although it seems to have no ill effects before that.
Fixing this is messier because we can now have situations where the same
query needs both the UPDATE-aligned set of GENERATED columns and the
INSERT-aligned set, and it's unclear which set will be generated first
(else we could hack things by forcing the INSERT-aligned set to be
generated, which is indeed how fe9e658f4 made it work for MERGE).
The best fix seems to be to build and store separate sets of expressions
for the INSERT and UPDATE cases.  That would create ABI issues in the
back branches, but so far it seems we can leave this alone in the back
branches.

Per bug #17823 from Hisahiro Kauchi.  The first part of this affects all
branches back to v12 where GENERATED columns were added.

Discussion: https://postgr.es/m/17823-b64909cf7d63de84@postgresql.org
2023-03-06 18:31:16 -05:00
Thomas Munro a0f55fc86a Fix assert failures in parallel SERIALIZABLE READ ONLY.
1.  Make sure that we don't decrement SxactGlobalXminCount twice when
the SXACT_FLAG_RO_SAFE optimization is reached in a parallel query.
This could trigger a sanity check failure in assert builds.  Non-assert
builds recompute the count in SetNewSxactGlobalXmin(), so the problem
was hidden, explaining the lack of field reports.  Add a new isolation
test to exercise that case.

2.  Remove an assertion that the DOOMED flag can't be set on a partially
released SERIALIZABLEXACT.  Instead, ignore the flag (our transaction
was already determined to be read-only safe, and DOOMED is in fact set
during partial release, and there was already an assertion that it
wasn't set sooner).  Improve an existing isolation test so that it
reaches that case (previously it wasn't quite testing what it was
supposed to be testing; see discussion).

Back-patch to 12.  Bug #17116.  Defects in commit 47a338cf.

Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/17116-d6ca217acc180e30%40postgresql.org
2023-03-06 16:28:34 +13:00
Tom Lane 3b37e84422 Avoid fetching one past the end of translate()'s "to" parameter.
This is usually harmless, but if you were very unlucky it could
provoke a segfault due to the "to" string being right up against
the end of memory.  Found via valgrind testing (so we might've
found it earlier, except that our regression tests lacked any
exercise of translate()'s deletion feature).

Fix by switching the order of the test-for-end-of-string and
advance-pointer steps.  While here, compute "to_ptr + tolen"
just once.  (Smarter compilers might figure that out for
themselves, but let's just make sure.)

Report and fix by Daniil Anisimov, in bug #17816.

Discussion: https://postgr.es/m/17816-70f3d2764e88a108@postgresql.org
2023-03-01 11:30:17 -05:00
Tom Lane 1e199c2599 Fix MULTIEXPR_SUBLINK with partitioned target tables, yet again.
We already tried to fix this in commits 3f7323cbb et al (and follow-on
fixes), but now it emerges that there are still unfixed cases;
moreover, these cases affect all branches not only pre-v14.  I thought
we had eliminated all cases of making multiple clones of an UPDATE's
target list when we nuked inheritance_planner.  But it turns out we
still do that in some partitioned-UPDATE cases, notably including
INSERT ... ON CONFLICT UPDATE, because ExecInitPartitionInfo thinks
it's okay to clone and modify the parent's targetlist.

This fix is based on a suggestion from Andres Freund: let's stop
abusing the ParamExecData.execPlan mechanism, which was only ever
meant to handle initplans, and instead solve the execution timing
problem by having the expression compiler move MULTIEXPR_SUBLINK steps
to the front of their expression step lists.  This is feasible because
(a) all branches still in support compile the entire targetlist of
an UPDATE into a single ExprState, and (b) we know that all
MULTIEXPR_SUBLINKs do need to be evaluated --- none could be buried
inside a CASE, for example.  There is a minor semantics change
concerning the order of execution of the MULTIEXPR's subquery versus
other parts of the parent targetlist, but that seems like something
we can get away with.  By doing that, we no longer need to worry
about whether different clones of a MULTIEXPR_SUBLINK share output
Params; their usage of that data structure won't overlap.

Per bug #17800 from Alexander Lakhin.  Back-patch to all supported
branches.  In v13 and earlier, we can revert 3f7323cbb and follow-on
fixes; however, I chose to keep the SubPlan.subLinkId field added
in ccbb54c72.  We don't need that anymore in the core code, but it's
cheap enough to fill, and removing a plan node field in a minor
release seems like it'd be asking for trouble.

Andres Freund and Tom Lane

Discussion: https://postgr.es/m/17800-ff90866b3906c964@postgresql.org
2023-02-25 14:44:14 -05:00
Dean Rasheed 39ad791e85 Fix mishandling of OLD/NEW references in subqueries in rule actions.
If a rule action contains a subquery that refers to columns from OLD
or NEW, then those are really lateral references, and the planner will
complain if it sees such things in a subquery that isn't marked as
lateral. However, at rule-definition time, the user isn't required to
mark the subquery with LATERAL, and so it can fail when the rule is
used.

Fix this by marking such subqueries as lateral in the rewriter, at the
point where they're used.

Dean Rasheed and Tom Lane, per report from Alexander Lakhin.
Back-patch to all supported branches.

Discussion: https://postgr.es/m/5e09da43-aaba-7ea7-0a51-a2eb981b058b%40gmail.com
2023-02-25 14:45:44 +00:00
Tom Lane 861e9e4860 Don't repeatedly register cache callbacks in pgoutput plugin.
Multiple cycles of starting up and shutting down the plugin within a
single session would eventually lead to "out of relcache_callback_list
slots", because pgoutput_startup blindly re-registered its cache
callbacks each time.  Fix it to register them only once, as all other
users of cache callbacks already take care to do.

This has been broken all along, so back-patch to all supported branches.

Shi Yu

Discussion: https://postgr.es/m/OSZPR01MB631004A78D743D68921FFAD3FDA79@OSZPR01MB6310.jpnprd01.prod.outlook.com
2023-02-23 15:40:28 -05:00
Dean Rasheed 226da3d476 Fix multi-row DEFAULT handling for INSERT ... SELECT rules.
Given an updatable view with a DO ALSO INSERT ... SELECT rule, a
multi-row INSERT ... VALUES query on the view fails if the VALUES list
contains any DEFAULTs that are not replaced by view defaults. This
manifests as an "unrecognized node type" error, or an Assert failure,
in an assert-enabled build.

The reason is that when RewriteQuery() attempts to replace the
remaining DEFAULT items with NULLs in any product queries, using
rewriteValuesRTEToNulls(), it assumes that the VALUES RTE is located
at the same rangetable index in each product query. However, if the
product query is an INSERT ... SELECT, then the VALUES RTE is actually
in the SELECT part of that query (at the same index), rather than the
top-level product query itself.

Fix, by descending to the SELECT in such cases. Note that we can't
simply use getInsertSelectQuery() for this, since that expects to be
given a raw rule action with OLD and NEW placeholder entries, so we
duplicate its logic instead.

While at it, beef up the checks in getInsertSelectQuery() by checking
that the jointree->fromlist node is indeed a RangeTblRef, and that the
RTE it points to has rtekind == RTE_SUBQUERY.

Per bug #17803, from Alexander Lakhin. Back-patch to all supported
branches.

Dean Rasheed, reviewed by Tom Lane.

Discussion: https://postgr.es/m/17803-53c63ed4ecb4eac6%40postgresql.org
2023-02-23 10:56:41 +00:00
Tomas Vondra 4df581fa0f Fix snapshot handling in logicalmsg_decode
Whe decoding a transactional logical message, logicalmsg_decode called
SnapBuildGetOrBuildSnapshot. But we may not have a consistent snapshot
yet at that point. We don't actually need the snapshot in this case
(during replay we'll have the snapshot from the transaction), so in
practice this is harmless. But in assert-enabled build this crashes.

Fixed by requesting the snapshot only in non-transactional case, where
we are guaranteed to have SNAPBUILD_CONSISTENT.

Backpatch to 11. The issue exists since 9.6.

Backpatch-through: 11
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/84d60912-6eab-9b84-5de3-41765a5449e8@enterprisedb.com
2023-02-22 16:09:30 +01:00
Dean Rasheed 906356cf61 Add missing support for the latest SPI status codes.
SPI_result_code_string() was missing support for SPI_OK_TD_REGISTER,
and in v15 and later, it was missing support for SPI_OK_MERGE, as was
pltcl_process_SPI_result().

The last of those would trigger an error if a MERGE was executed from
PL/Tcl. The others seem fairly innocuous, but worth fixing.

Back-patch to all supported branches. Before v15, this is just adding
SPI_OK_TD_REGISTER to SPI_result_code_string(), which is unlikely to
be seen by anyone, but seems worth doing for completeness.

Reviewed by Tom Lane.

Discussion:
  https://postgr.es/m/CAEZATCUg8V%2BK%2BGcafOPqymxk84Y_prXgfe64PDoopjLFH6Z0Aw%40mail.gmail.com
  https://postgr.es/m/CAEZATCUMe%2B_KedPMM9AxKqm%3DSZogSxjUcrMe%2BsakusZh3BFcQw%40mail.gmail.com
2023-02-22 13:27:29 +00:00
Tom Lane 99e74cd235 Fix erroneous Valgrind markings in AllocSetRealloc.
If asked to decrease the size of a large (>8K) palloc chunk,
AllocSetRealloc could improperly change the Valgrind state of memory
beyond the new end of the chunk: it would mark data UNDEFINED as far
as the old end of the chunk after having done the realloc(3) call,
thus tromping on the state of memory that no longer belongs to it.
One would normally expect that memory to now be marked NOACCESS,
so that this mislabeling might prevent detection of later errors.
If realloc() had chosen to move the chunk someplace else (unlikely,
but well within its rights) we could also mismark perfectly-valid
DEFINED data as UNDEFINED, causing false-positive valgrind reports
later.  Also, any malloc bookkeeping data placed within this area
might now be wrongly marked, causing additional problems.

Fix by replacing relevant uses of "oldsize" with "Min(size, oldsize)".
It's sufficient to mark as far as "size" when that's smaller, because
whatever remains in the new chunk size will be marked NOACCESS below,
and we expect realloc() to have taken care of marking the memory
beyond the new official end of the chunk.

While we're here, also rename the function's "oldsize" variable
to "oldchksize" to more clearly explain what it actually holds,
namely the distance to the end of the chunk (that is, requested size
plus trailing padding).  This is more consistent with the use of
"size" and "chksize" to hold the new requested size and chunk size.
Add a new variable "oldsize" in the one stanza where we're actually
talking about the old requested size.

Oversight in commit c477f3e44.  Back-patch to all supported branches,
as that was, just in case anybody wants to do valgrind testing on back
branches.

Karina Litskevich

Discussion: https://postgr.es/m/CACiT8iaAET-fmzjjZLjaJC4zwSJmrFyL7LAdHwaYyjjQOQ4hcg@mail.gmail.com
2023-02-21 18:47:47 -05:00
Tom Lane 4efb4f0d48 Print the correct aliases for DML target tables in ruleutils.
ruleutils.c blindly printed the user-given alias (or nothing if there
hadn't been one) for the target table of INSERT/UPDATE/DELETE queries.
That works a large percentage of the time, but not always: for queries
appearing in WITH, it's possible that we chose a different alias to
avoid conflict with outer-scope names.  Since the chosen alias would
be used in any Var references to the target table, this'd lead to an
inconsistent printout with consequences such as dump/restore failures.

The correct logic for printing (or not) a relation alias was embedded
in get_from_clause_item.  Factor it out to a separate function so that
we don't need a jointree node to use it.  (Only a limited part of that
function can be reached from these new call sites, but this seems like
the cleanest non-duplicative factorization.)

In passing, I got rid of a redundant "\d+ rules_src" step in rules.sql.

Initial report from Jonathan Katz; thanks to Vignesh C for analysis.
This has been broken for a long time, so back-patch to all supported
branches.

Discussion: https://postgr.es/m/e947fa21-24b2-f922-375a-d4f763ef3e4b@postgresql.org
Discussion: https://postgr.es/m/CALDaNm1MMntjmT_NJGp-Z=xbF02qHGAyuSHfYHias3TqQbPF2w@mail.gmail.com
2023-02-17 16:40:34 -05:00
Michael Paquier 2eb8e54cc3 Fix handling of SCRAM-SHA-256's channel binding with RSA-PSS certificates
OpenSSL 1.1.1 and newer versions have added support for RSA-PSS
certificates, which requires the use of a specific routine in OpenSSL to
determine which hash function to use when compiling it when using
channel binding in SCRAM-SHA-256.  X509_get_signature_nid(), that is the
original routine the channel binding code has relied on, is not able to
determine which hash algorithm to use for such certificates.  However,
X509_get_signature_info(), new to OpenSSL 1.1.1, is able to do it.  This
commit switches the channel binding logic to rely on
X509_get_signature_info() over X509_get_signature_nid(), which would be
the choice when building with 1.1.1 or newer.

The error could have been triggered on the client or the server, hence
libpq and the backend need to have their related code paths patched.
Note that attempting to load an RSA-PSS certificate with OpenSSL 1.1.0
or older leads to a failure due to an unsupported algorithm.

The discovery of relying on X509_get_signature_info() comes from Jacob,
the tests have been written by Heikki (with few tweaks from me), while I
have bundled the whole together while adding the bits needed for MSVC
and meson.

This issue exists since channel binding exists, so backpatch all the way
down.  Some tests are added in 15~, triggered if compiling with OpenSSL
1.1.1 or newer, where the certificate and key files can easily be
generated for RSA-PSS.

Reported-by: Gunnar "Nick" Bluth
Author: Jacob Champion, Heikki Linnakangas
Discussion: https://postgr.es/m/17760-b6c61e752ec07060@postgresql.org
Backpatch-through: 11
2023-02-15 10:12:36 +09:00
David Rowley 301eb3ee4e Disable WindowAgg inverse transitions when subplans are present
When an aggregate function is used as a WindowFunc and a tuple transitions
out of the window frame, we ordinarily try to make use of the aggregate
function's inverse transition function to "unaggregate" the exiting tuple.

This optimization is disabled for various cases, including when the
aggregate contains a volatile function.  In such a case we'd be unable to
ensure that the transition value was calculated to the same value during
transitions and inverse transitions.  Unfortunately, we did this check by
calling contain_volatile_functions() which does not recursively search
SubPlans for volatile functions.  If the aggregate function's arguments or
its FILTER clause contained a subplan with volatile functions then we'd
fail to notice this.

Here we fix this by just disabling the optimization when the WindowFunc
contains any subplans.  Volatile functions are not the only reason that a
subplan may have nonrepeatable results.

Bug: #17777
Reported-by: Anban Company
Discussion: https://postgr.es/m/17777-860b739b6efde977%40postgresql.org
Reviewed-by: Tom Lane
Backpatch-through: 11
2023-02-13 17:09:26 +13:00
Peter Eisentraut 07113f15cd Translation updates
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: a7bebd06a02093ea07899fc0804adeb372126620
2023-02-06 12:18:46 +01:00
Thomas Munro 1a5afe0077 Fix rare sharedtuplestore.c corruption.
If the final chunk of an oversized tuple being written out to disk was
exactly 32760 bytes, it would be corrupted due to a fencepost bug.

Bug #17619.  Back-patch to 11 where the code arrived.

While testing that (see test module in archives), I (tmunro) noticed
that the per-participant page counter was not initialized to zero as it
should have been; that wasn't a live bug when it was written since DSM
memory was originally always zeroed, but since 14
min_dynamic_shared_memory might be configured and it supplies non-zeroed
memory, so that is also fixed here.

Author: Dmitry Astapov <dastapov@gmail.com>
Discussion: https://postgr.es/m/17619-0de62ceda812b8b5%40postgresql.org
2023-01-26 14:54:39 +13:00
Andres Freund c5864805ba Fix error handling in libpqrcv_connect()
When libpqrcv_connect (also known as walrcv_connect()) failed, it leaked the
libpq connection. In most paths that's fairly harmless, as the calling process
will exit soon after. But e.g. CREATE SUBSCRIPTION could lead to a somewhat
longer lived leak.

Fix by releasing resources, including the libpq connection, on error.

Add a test exercising the error code path. To make it reliable and safe, the
test tries to connect to port=-1, which happens to fail during connection
establishment, rather than during connection string parsing.

Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20230121011237.q52apbvlarfv6jm6@awork3.anarazel.de
Backpatch: 11-
2023-01-23 18:27:51 -08:00
Tom Lane 72d611109e Allow REPLICA IDENTITY to be set on an index that's not (yet) valid.
The motivation for this change is that when pg_dump dumps a
partitioned index that's marked REPLICA IDENTITY, it generates a
command sequence that applies REPLICA IDENTITY before the partitioned
index has been marked valid, causing restore to fail.  We could
perhaps change pg_dump to not do it like that, but that would be
difficult and would not fix existing dump files with the problem.
There seems to be very little reason for the backend to disallow
this anyway --- the code ignores indisreplident when the index
isn't valid --- so instead let's fix it by allowing the case.

Commit 9511fb37a previously expressed a concern that allowing
indisreplident to be set on invalid indexes might allow us to
wind up in a situation where a table could have indisreplident
set on multiple indexes.  I'm not sure I follow that concern
exactly, but in any case the only way that could happen is because
relation_mark_replica_identity is too trusting about the existing set
of markings being valid.  Let's just rip out its early-exit code path
(which sure looks like premature optimization anyway; what are we
doing expending code to make redundant ALTER TABLE ... REPLICA
IDENTITY commands marginally faster and not-redundant ones marginally
slower?) and fix it to positively guarantee that no more than one
index is marked indisreplident.

The pg_dump failure can be demonstrated in all supported branches,
so back-patch all the way.  I chose to back-patch 9511fb37a as well,
just to keep indisreplident handling the same in all branches.

Per bug #17756 from Sergey Belyashov.

Discussion: https://postgr.es/m/17756-dd50e8e0c8dd4a40@postgresql.org
2023-01-21 13:10:29 -05:00
Noah Misch a9bccffe5a Reject CancelRequestPacket having unexpected length.
When the length was too short, the server read outside the allocation.
That yielded the same log noise as sending the correct length with
(backendPID,cancelAuthCode) matching nothing.  Change to a message about
the unexpected length.  Given the attacker's lack of control over the
memory layout and the general lack of diversity in memory layouts at the
code in question, we doubt a would-be attacker could cause a segfault.
Hence, while the report arrived via security@postgresql.org, this is not
a vulnerability.  Back-patch to v11 (all supported versions).

Andrey Borodin, reviewed by Tom Lane.  Reported by Andrey Borodin.
2023-01-21 06:08:04 -08:00
Tom Lane 1b9a0b96a8 Log the correct ending timestamp in recovery_target_xid mode.
When ending recovery based on recovery_target_xid matching with
recovery_target_inclusive = off, we printed an incorrect timestamp
(always 2000-01-01) in the "recovery stopping before ... transaction"
log message.  This is a consequence of sloppy refactoring in
c945af80c: the code to fetch recordXtime out of the commit/abort
record used to be executed unconditionally, but it was changed
to get called only in the RECOVERY_TARGET_TIME case.  We need only
flip the order of operations to restore the intended behavior.

Per report from Torsten Förtsch.  Back-patch to all supported
branches.

Discussion: https://postgr.es/m/CAKkG4_kUevPqbmyOfLajx7opAQk6Cvwkvx0HRcFjSPfRPTXanA@mail.gmail.com
2023-01-19 12:23:20 -05:00
Michael Paquier fed4e92f3b Add missing assign hook for GUC checkpoint_completion_target
This is wrong since 88e9823, that has switched the WAL sizing
configuration from checkpoint_segments to min_wal_size and
max_wal_size.  This missed the recalculation of the internal value of
the internal "CheckPointSegments", that works as a mapping of the old
GUC checkpoint_segments, on reload, for example, and it controls the
timing of checkpoints depending on the volume of WAL generated.

Most users tend to leave checkpoint_completion_target at 0.9 to smooth
the I/O workload, which is why I guess this has gone unnoticed for so
long, still it can be useful to tweak and reload the value dynamically
in some cases to control the timing of checkpoints.

Author: Bharath Rupireddy
Discussion: https://postgr.es/m/CALj2ACXgPPAm28mruojSBno+F_=9cTOOxHAywu_dfZPeBdybQw@mail.gmail.com
Backpatch-through: 11
2023-01-19 13:13:30 +09:00
Peter Eisentraut cf74b6eadb Fix some BufFileRead() error reporting
Remove "%m" from error messages where errno would be bogus.  Add short
read byte counts where appropriate.

This is equivalent to what was done in
7897e3bb90, but some code was apparently
developed concurrently to that and not updated accordingly.

Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/f3501945-c591-8cc3-5ef0-b72a2e0eaa9c@enterprisedb.com
2023-01-16 09:54:15 +01:00
Tom Lane 787db4be94 Make new GENERATED-expressions code more bulletproof.
In commit 8bf6ec3ba I assumed that no code path could reach
ExecGetExtraUpdatedCols without having gone through
ExecInitStoredGenerated.  That turns out not to be the case in
logical replication: if there's an ON UPDATE trigger on the target
table, trigger.c will call this code before anybody has set up its
generated columns.  Having seen that, I don't have a lot of faith in
there not being other such paths.  ExecGetExtraUpdatedCols can call
ExecInitStoredGenerated for itself, as long as we are willing to
assume that it is only called in CMD_UPDATE operations, which on
the whole seems like a safer leap of faith.

Per report from Vitaly Davydov.

Discussion: https://postgr.es/m/d259d69652b8c2ff50e14cda3c236c7f@postgrespro.ru
2023-01-15 14:06:46 -05:00
Thomas Munro c159b0383f Fix WaitEventSetWait() buffer overrun.
The WAIT_USE_EPOLL and WAIT_USE_KQUEUE implementations of
WaitEventSetWaitBlock() confused the size of their internal buffer with
the size of the caller's output buffer, and could ask the kernel for too
many events.  In fact the set of events retrieved from the kernel needs
to be able to fit in both buffers, so take the smaller of the two.

The WAIT_USE_POLL and WAIT_USE WIN32 implementations didn't have this
confusion.

This probably didn't come up before because we always used the same
number in both places, but commit 7389aad6 calculates a dynamic size at
construction time, while using MAXLISTEN for its output event buffer on
the stack.  That seems like a reasonable thing to want to do, so
consider this to be a pre-existing bug worth fixing.

As discovered by valgrind on skink.

Back-patch to all supported releases for epoll, and to release 13 for
the kqueue part, which copied the incorrect epoll code.

Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/901504.1673504836%40sss.pgh.pa.us
2023-01-13 10:54:49 +13:00
Alexander Korotkov 2ff3ac3b5f Fix jsonpath existense checking of missing variables
The current jsonpath code assumes that the referenced variable always exists.
It could only throw an error at the value valuation time.  At the same time
existence checking assumes variable is present without valuation, and error
suppression doesn't work for missing variables.

This commit makes existense checking trigger an error for missing variables.
This makes the overall behavior consistent.

Backpatch to 12 where jsonpath was introduced.

Reported-by: David G. Johnston
Discussion: https://postgr.es/m/CAKFQuwbeytffJkVnEqDyLZ%3DrQsznoTh1OgDoOF3VmOMkxcTMjA%40mail.gmail.com
Author: Alexander Korotkov, David G. Johnston
Backpatch-through: 12
2023-01-12 18:18:31 +03:00
Michael Paquier 72b6098be4 Avoid using tuple from syscache for update of pg_database.datfrozenxid
pg_database.datfrozenxid gets updated using an in-place update at the
end of vacuum or autovacuum.  Since 96cdeae, as pg_database has a toast
relation, it is possible for a pg_database tuple to have toast values
if there is a large set of ACLs in place.  In such a case, the in-place
update would fail because of the flattening of the toast values done for
the catcache entry fetched.  Instead of using a copy from the catcache,
this changes the logic to fetch the copy of the tuple by directly
scanning pg_database.

Note that before 96cdeae, attempting to insert such a tuple to
pg_database would cause a "row is too big" error, so the end-of-vacuum
problem was not reachable.

This issue has been originally fixed in 947789f on v14~, and there have
been reports about this problem on v12 and v13, causing failures at the
end of VACUUM.  This completes the fix on all the stable branches where
pg_database can use a toast table, down to 12.

Author: Ashwin Agrawal, Junfeng Yang
Discussion: https://postgr.es/m/DM5PR0501MB38800D9E4605BCA72DD35557CCE10@DM5PR0501MB3880.namprd05.prod.outlook.com
Discussion: https://postgr.es/m/Y70XNVbUWQsR2Car@paquier.xyz
Backpatch-through: 12
2023-01-11 09:56:14 +09:00
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
Michael Paquier 1c89549ca4 Fix typos in comments, code and documentation
While on it, newlines are removed from the end of two elog() strings.
The others are simple grammar mistakes.  One comment in pg_upgrade
referred incorrectly to sequences since a7e5457.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20221230231257.GI1153@telsasoft.com
Backpatch-through: 11
2023-01-03 16:26:34 +09:00
Tom Lane 19adcaf00f Avoid reference to nonexistent array element in ExecInitAgg().
When considering an empty grouping set, we fetched
phasedata->eqfunctions[-1].  Because the eqfunctions array is
palloc'd, that would always be an aset pointer in released versions,
and thus the code accidentally failed to malfunction (since it would
do nothing unless it found a null pointer).  Nonetheless this seems
like trouble waiting to happen, so add a check for length == 0.

It's depressing that our valgrind testing did not catch this.
Maybe we should reconsider the choice to not mark that word NOACCESS?

Richard Guo

Discussion: https://postgr.es/m/CAMbWs4-vZuuPOZsKOYnSAaPYGKhmacxhki+vpOKk0O7rymccXQ@mail.gmail.com
2023-01-02 16:17:00 -05:00
Michael Paquier 4dbe72d61a Fix come incorrect elog() messages in aclchk.c
Three error strings used with cache lookup failures were referring to
incorrect object types for ACL checks:
- Schemas
- Types
- Foreign Servers
There errors should never be triggered, but if they do incorrect
information would be reported.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20221222153041.GN1153@telsasoft.com
Backpatch-through: 11
2022-12-23 10:04:34 +09:00
Tom Lane 4fceb454f2 Add some recursion and looping defenses in prepjointree.c.
Andrey Lepikhov demonstrated a case where we spend an unreasonable
amount of time in pull_up_subqueries().  Not only is that recursing
with no explicit check for stack overrun, but the code seems not
interruptable by control-C.  Let's stick a CHECK_FOR_INTERRUPTS
there, along with sprinkling some stack depth checks.

An actual fix for the excessive time consumption seems a bit
risky to back-patch; but this isn't, so let's do so.

Discussion: https://postgr.es/m/703c09a2-08f3-d2ec-b33d-dbecd62428b8@postgrespro.ru
2022-12-22 10:35:03 -05:00
Tom Lane 942cc240f9 Rethink handling of [Prevent|Is]InTransactionBlock in pipeline mode.
Commits f92944137 et al. made IsInTransactionBlock() set the
XACT_FLAGS_NEEDIMMEDIATECOMMIT flag before returning "false",
on the grounds that that kept its API promises equivalent to those of
PreventInTransactionBlock().  This turns out to be a bad idea though,
because it allows an ANALYZE in a pipelined series of commands to
cause an immediate commit, which is unexpected.

Furthermore, if we return "false" then we have another issue,
which is that ANALYZE will decide it's allowed to do internal
commit-and-start-transaction sequences, thus possibly unexpectedly
committing the effects of previous commands in the pipeline.

To fix the latter situation, invent another transaction state flag
XACT_FLAGS_PIPELINING, which explicitly records the fact that we
have executed some extended-protocol command and not yet seen a
commit for it.  Then, require that flag to not be set before allowing
InTransactionBlock() to return "false".

Having done that, we can remove its setting of NEEDIMMEDIATECOMMIT
without fear of causing problems.  This means that the API guarantees
of IsInTransactionBlock now diverge from PreventInTransactionBlock,
which is mildly annoying, but it seems OK given the very limited usage
of IsInTransactionBlock.  (In any case, a caller preferring the old
behavior could always set NEEDIMMEDIATECOMMIT for itself.)

For consistency also require XACT_FLAGS_PIPELINING to not be set
in PreventInTransactionBlock.  This too is meant to prevent commands
such as CREATE DATABASE from silently committing previous commands
in a pipeline.

Per report from Peter Eisentraut.  As before, back-patch to all
supported branches (which sadly no longer includes v10).

Discussion: https://postgr.es/m/65a899dd-aebc-f667-1d0a-abb89ff3abf8@enterprisedb.com
2022-12-13 14:23:59 -05:00
Tom Lane 4ebca555cf Fix generate_partitionwise_join_paths() to tolerate failure.
We might fail to generate a partitionwise join, because
reparameterize_path_by_child() does not support all path types.
This should not be a hard failure condition: we should just fall back
to a non-partitioned join.  However, generate_partitionwise_join_paths
did not consider this possibility and would emit the (misleading)
error "could not devise a query plan for the given query" if we'd
failed to make any paths for a child join.  Fix it to give up on
partitionwise joining if so.  (The accepted technique for giving up
appears to be to set rel->nparts = 0, which I find pretty bizarre,
but there you have it.)

I have not added a test case because there'd be little point:
any omissions of this sort that we identify would soon get fixed
by extending reparameterize_path_by_child(), so the test would stop
proving anything.  However, right now there is a known test case based
on failure to cover MaterialPath, and with that I've found that this
is broken in all supported versions.  Hence, patch all the way back.

Original report and patch by me; thanks to Richard Guo for
identifying a test case that works against committed versions.

Discussion: https://postgr.es/m/1854233.1669949723@sss.pgh.pa.us
2022-12-04 13:17:18 -05:00
Dean Rasheed 3bed881237 Fix DEFAULT handling for multi-row INSERT rules.
When updating a relation with a rule whose action performed an INSERT
from a multi-row VALUES list, the rewriter might skip processing the
VALUES list, and therefore fail to replace any DEFAULTs in it. This
would lead to an "unrecognized node type" error.

The reason was that RewriteQuery() assumed that a query doing an
INSERT from a multi-row VALUES list would necessarily only have one
item in its fromlist, pointing to the VALUES RTE to read from. That
assumption is correct for the original query, but not for product
queries produced for rule actions. In such cases, there may be
multiple items in the fromlist, possibly including multiple VALUES
RTEs.

What is required instead is for RewriteQuery() to skip any RTEs from
the product query's originating query, which might include one or more
already-processed VALUES RTEs. What's left should then include at most
one VALUES RTE (from the rule action) to be processed.

Patch by me. Thanks to Tom Lane for reviewing.

Back-patch to all supported branches.

Discussion: https://postgr.es/m/CAEZATCV39OOW7LAR_Xq4i%2BLc1Byux%3DeK3Q%3DHD_pF1o9LBt%3DphA%40mail.gmail.com
2022-12-03 12:17:47 +00:00
Jeff Davis a844052b5d Fix memory leak for hashing with nondeterministic collations.
Backpatch through 12, where nondeterministic collations were
introduced (5e1963fb76).

Backpatch-through: 12
2022-12-01 11:52:06 -08:00
Tom Lane 6e8ad11521 Improve heuristics for compressing the KnownAssignedXids array.
Previously, we'd compress only when the active range of array entries
reached Max(4 * PROCARRAY_MAXPROCS, 2 * pArray->numKnownAssignedXids).
If max_connections is large, the first term could result in not
compressing for a long time, resulting in much wastage of cycles in
hot-standby backends scanning the array to take snapshots.  Get rid
of that term, and just bound it to 2 * pArray->numKnownAssignedXids.

That however creates the opposite risk, that we might spend too much
effort compressing.  Hence, consider compressing only once every 128
commit records.  (This frequency was chosen by benchmarking.  While
we only tried one benchmark scenario, the results seem stable over
a fairly wide range of frequencies.)

Also, force compression when processing RecoveryInfo WAL records
(which should be infrequent); the old code could perform compression
then, but would do so only after the same array-range check as for
the transaction-commit path.

Also, opportunistically run compression if the startup process is about
to wait for WAL, though not oftener than once a second.  This should
prevent cases where we waste lots of time by leaving the array
not-compressed for long intervals due to low WAL traffic.

Lastly, add a simple check to keep us from uselessly compressing
when the array storage is already compact.

Back-patch, as the performance problem is worse in pre-v14 branches
than in HEAD.

Simon Riggs and Michail Nikolaev, with help from Tom Lane and
Andres Freund.

Discussion: https://postgr.es/m/CALdSSPgahNUD_=pB_j=1zSnDBaiOtqVfzo8Ejt5J_k7qZiU1Tw@mail.gmail.com
2022-11-29 15:43:17 -05:00
Tom Lane aca695fb68 Remove bogus Assert and dead code in remove_useless_results_recurse().
The JOIN_SEMI case Assert'ed that there are no PlaceHolderVars that
need to be evaluated at the semijoin's RHS, which is wrong because
there could be some in the semijoin's qual condition.  However, there
could not be any references further up than that, and within the qual
there is not any way that such a PHV could have gone to null yet, so
we don't really need the PHV and there is no need to avoid making the
RHS-removal optimization.  The upshot is that there's no actual bug
in production code, and we ought to just remove this misguided Assert.

While we're here, also drop the JOIN_RIGHT case, which is dead code
because reduce_outer_joins() already got rid of JOIN_RIGHT.

Per bug #17700 from Xin Wen.  Uselessness of the JOIN_RIGHT case
pointed out by Richard Guo.  Back-patch to v12 where this code
was added.

Discussion: https://postgr.es/m/17700-2b5c10d917c30687@postgresql.org
2022-11-29 10:52:44 -05:00
Amit Kapila 4ec157c150 Fix uninitialized access to InitialRunningXacts during decoding.
In commit 272248a0c, we introduced an InitialRunningXacts array to
remember transactions and subtransactions that were running when the
xl_running_xacts record that we decoded was written. This array was
allocated in the snapshot builder memory context after we restore
serialized snapshot but we forgot to reset the array while freeing the
builder memory context. So, the next time when we start decoding in the
same session where we don't restore any serialized snapshot, we ended up
using the uninitialized array and that can lead to unpredictable behavior.

This problem doesn't exist in HEAD as instead of using
InitialRunningXacts, we added 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).

Reported-by: Maxim Orlov
Author: Masahiko Sawada
Reviewed-by: Amit Kapila, Maxim Orlov
Backpatch-through: 11
Discussion: https://postgr.es/m/CACG=ezZoz_KG+Ryh9MrU_g5e0HiVoHocEvqFF=NRrhrwKmEQJQ@mail.gmail.com
2022-11-25 09:15:31 +05:30
Alvaro Herrera 5a185246f9
Make multixact error message more explicit
There are recent reports involving a very old error message that we have
no history of hitting -- perhaps a recently introduced bug.  Improve the
error message in an attempt to improve our chances of investigating the
bug.

Per reports from Dimos Stamatakis and Bob Krier.

Backpatch to 11.

Discussion: https://postgr.es/m/CO2PR0801MB2310579F65529380A4E5EDC0E20A9@CO2PR0801MB2310.namprd08.prod.outlook.com
Discussion: https://postgr.es/m/17518-04e368df5ad7f2ee@postgresql.org
2022-11-24 10:45:10 +01:00
Tom Lane 6e639267a5 YA attempt at taming worst-case behavior of get_actual_variable_range.
We've made multiple attempts at preventing get_actual_variable_range
from taking an unreasonable amount of time (3ca930fc3, fccebe421).
But there's still an issue for the very first planning attempt after
deletion of a large number of extremal-valued tuples.  While that
planning attempt will set "killed" bits on the tuples it visits and
thereby reduce effort for next time, there's still a lot of work it
has to do to visit the heap and then set those bits.  It's (usually?)
not worth it to do that much work at plan time to have a slightly
better estimate, especially in a context like this where the table
contents are known to be mutating rapidly.

Therefore, let's bound the amount of work to be done by giving up
after we've visited 100 heap pages.  Giving up just means we'll
fall back on the extremal value recorded in pg_statistic, so it
shouldn't mean that planner estimates suddenly become worthless.

Note that this means we'll still gradually whittle down the problem
by setting a few more index "killed" bits in each planning attempt;
so eventually we'll reach a good state (barring further deletions),
even in the absence of VACUUM.

Simon Riggs, per a complaint from Jakub Wartak (with cosmetic
adjustments by me).  Back-patch to all supported branches.

Discussion: https://postgr.es/m/CAKZiRmznOwi0oaV=4PHOCM4ygcH4MgSvt8=5cu_vNCfc8FSUug@mail.gmail.com
2022-11-22 14:40:45 -05:00
Alvaro Herrera 36eeb37cd6
Ignore invalidated slots while computing oldest catalog Xmin
Once a logical slot has acquired a catalog_xmin, it doesn't let go of
it, even when invalidated by exceeding the max_slot_wal_keep_size, which
means that dead catalog tuples are not removed by vacuum anymore since
the point is invalidated, until the slot is dropped.  This could be
catastrophic if catalog churn is high.

Change the computation of Xmin to ignore invalidated slots,
to prevent dead rows from accumulating.

Backpatch to 13, where slot invalidation appeared.

Author: Sirisha Chamarthi <sirichamarthi22@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/CAKrAKeUEDeqquN9vwzNeG-CN8wuVsfRYbeOUV9qKO_RHok=j+g@mail.gmail.com
2022-11-22 10:56:07 +01:00
Tom Lane 74670688fa Add comments and a missing CHECK_FOR_INTERRUPTS in ts_headline.
I just spent an annoying amount of time reverse-engineering the
100%-undocumented API between ts_headline and the text search
parser's prsheadline function.  Add some commentary about that
while it's fresh in mind.  Also remove some unused macros in
wparser_def.c.

While at it, I noticed that when commit 78e73e875 added a
CHECK_FOR_INTERRUPTS call in TS_execute_recurse, it missed
doing so in the parallel function TS_phrase_execute, which
surely needs one just as much.

Back-patch because of the missing CHECK_FOR_INTERRUPTS.
Might as well back-patch the rest of this too.
2022-11-21 17:07:07 -05:00
Andres Freund c13667b518 Fix mislabeling of PROC_QUEUE->links as PGPROC, fixing UBSan on 32bit
ProcSleep() used a PGPROC* variable to point to PROC_QUEUE->links.next,
because that does "the right thing" with SHMQueueInsertBefore(). While that
largely works, it's certainly not correct and unnecessary - we can just use
SHM_QUEUE* to point to the insertion point.

Noticed when testing a 32bit of postgres with undefined behavior
sanitizer. UBSan noticed that sometimes the supposed PGPROC wasn't
sufficiently aligned (required since 46d6e5f567, ensured indirectly, via
ShmemAllocRaw() guaranteeing cacheline alignment).

For now fix this by using a SHM_QUEUE* for the insertion point. Subsequently
we should replace all the use of PROC_QUEUE and SHM_QUEUE with ilist.h, but
that's a larger change that we don't want to backpatch.

Backpatch to all supported versions - it's useful to be able to run postgres
under UBSan.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20221117014230.op5kmgypdv2dtqsf@awork3.anarazel.de
Backpatch: 11-
2022-11-19 12:36:33 -08:00
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
Amit Kapila 20c2233363 Fix cleanup lock acquisition in SPLIT_ALLOCATE_PAGE replay.
During XLOG_HASH_SPLIT_ALLOCATE_PAGE replay, we were checking for a
cleanup lock on the new bucket page after acquiring an exclusive lock on
it and raising a PANIC error on failure. However, it is quite possible
that checkpointer can acquire the pin on the same page before acquiring a
lock on it, and then the replay will lead to an error. So instead, directly
acquire the cleanup lock on the new bucket page during
XLOG_HASH_SPLIT_ALLOCATE_PAGE replay operation.

Reported-by: Andres Freund
Author: Robert Haas
Reviewed-By: Amit Kapila, Andres Freund, Vignesh C
Backpatch-through: 11
Discussion: https://postgr.es/m/20220810022617.fvjkjiauaykwrbse@awork3.anarazel.de
2022-11-14 10:11:10 +05:30
Jeff Davis 58a45bb1d8 Fix theoretical torn page hazard.
The original report was concerned with a possible inconsistency
between the heap and the visibility map, which I was unable to
confirm. The concern has been retracted.

However, there did seem to be a torn page hazard when using
checksums. By not setting the heap page LSN during redo, the
protections of minRecoveryPoint were bypassed. Fixed, along with a
misleading comment.

It may have been impossible to hit this problem in practice, because
it would require a page tear between the checksum and the flags, so I
am marking this as a theoretical risk. But, as discussed, it did
violate expectations about the page LSN, so it may have other
consequences.

Backpatch to all supported versions.

Reported-by: Konstantin Knizhnik
Reviewed-by: Konstantin Knizhnik
Discussion: https://postgr.es/m/fed17dac-8cb8-4f5b-d462-1bb4908c029e@garret.ru
Backpatch-through: 11
2022-11-11 12:46:34 -08:00
Tom Lane 1949135e79 Doc: add comments about PreventInTransactionBlock/IsInTransactionBlock.
Add a little to the header comments for these functions to make it
clearer what guarantees about commit behavior are provided to callers.
(See commit f92944137 for context.)

Although this is only a comment change, it's really documentation
aimed at authors of extensions, so it seems appropriate to back-patch.

Yugo Nagata and Tom Lane, per further discussion of bug #17434.

Discussion: https://postgr.es/m/17434-d9f7a064ce2a88a3@postgresql.org
2022-11-09 11:08:52 -05:00
Peter Eisentraut 5680c5de32 Translation updates
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: 93ab2efcf9d6fb34739c57e61d57ae37e1fb03d3
2022-11-07 13:57:17 +01:00
Etsuro Fujita 26c1cab4c9 Correct error message for row-level triggers with transition tables on partitioned tables.
"Triggers on partitioned tables cannot have transition tables." is
incorrect as we allow statement-level triggers on partitioned tables to
have transition tables.

This has been wrong since commit 86f575948; back-patch to v11 where that
commit came in.

Reviewed by Tom Lane.

Discussion: https://postgr.es/m/CAPmGK17gk4vXLzz2iG%2BG4LWRWCoVyam70nZ3OuGm1hMJwDrhcg%40mail.gmail.com
2022-11-04 19:15:04 +09:00
Alvaro Herrera 41b6e7c9a3
Create FKs properly when attaching table as partition
Commit f56f8f8da6 added some code in CloneFkReferencing that's way too
lax about a Constraint node it manufactures, not initializing enough
struct members -- initially_valid in particular was forgotten.  This
causes some FKs in partitions added by ALTER TABLE ATTACH PARTITION to
be marked as not validated.  Set initially_valid true, which fixes the
bug.

While at it, make the struct initialization more complete.  Very similar
code was added in two other places by the same commit; make them all
follow the same pattern for consistency, though no bugs are apparent
there.

This bug has never been reported: I only happened to notice while
working on commit 614a406b4f.  The test case that was added there with
the improper result is repaired.

Backpatch to 12.

Discussion: https://postgr.es/m/20221005105523.bhuhkdx4olajboof@alvherre.pgsql
2022-11-03 20:40:21 +01:00
Tom Lane b00f342ea0 Avoid crash after function syntax error in a replication worker.
If a syntax error occurred in a SQL-language or PL/pgSQL-language
CREATE FUNCTION or DO command executed in a logical replication worker,
we'd suffer a null pointer dereference or assertion failure.  That
seems like a rather contrived case, but nonetheless worth fixing.

The cause is that function_parse_error_transpose assumes it must be
executing within the context of a Portal, but logical/worker.c
doesn't create a Portal since it's not running the standard executor.
We can just back off the hard Assert check and make it fail gracefully
if there's not an ActivePortal.  (I have a feeling that the aggressive
check here was my fault originally, probably because I wasn't sure if
the case would always hold and wanted to find out.  Well, now we know.)

The hazard seems to exist in all branches that have logical replication,
so back-patch to v10.

Maxim Orlov, Anton Melnikov, Masahiko Sawada, Tom Lane

Discussion: https://postgr.es/m/b570c367-ba38-95f3-f62d-5f59b9808226@inbox.ru
Discussion: https://postgr.es/m/adf0452f-8c6b-7def-d35e-ab516c80088e@inbox.ru
2022-11-03 12:01:57 -04:00
Tom Lane 4d3f7e75c8 Defend against unsupported partition relkind in logical replication worker.
Since partitions can be foreign tables not only plain tables, but
logical replication only supports plain tables, we'd better check the
relkind of a partition after we find it.  (There was some discussion
of checking this when adding a partitioned table to a subscription;
but that would be inadequate since the troublesome partition could be
added later.)  Without this, the situation leads to a segfault or
assertion failure.

In passing, add a separate variable for the target Relation of
a cross-partition UPDATE; reusing partrel seemed mighty confusing
and error-prone.

Shi Yu and Tom Lane, per report from Ilya Gladyshev.  Back-patch
to v13 where logical replication into partitioned tables became
a thing.

Discussion: https://postgr.es/m/6b93e3748ba43298694f376ca8797279d7945e29.camel@gmail.com
2022-11-02 12:29:39 -04:00
Etsuro Fujita 197cbca6bc Fix copy-and-pasteo in comment. 2022-11-02 18:15:05 +09:00
Michael Paquier 594b97509e Fix ordering issue with WAL operations in GIN fast insert path
Contrary to what is documented in src/backend/access/transam/README,
ginHeapTupleFastInsert() had a few ordering issues with the way it does
its WAL operations when inserting items in its fast path.

First, when using a separate list, XLogBeginInsert() was being always
called before START_CRIT_SECTION(), and in this case a second thing was
wrong when merging lists, as an exclusive lock was taken on the tail
page *before* calling XLogBeginInsert().  Finally, when inserting items
into a tail page, the order of XLogBeginInsert() and
START_CRIT_SECTION() was reversed.  This commit addresses all these
issues by moving the calls of XLogBeginInsert() after all the pages
logged are locked and pinned, within a critical section.

This has been applied first only on HEAD as of 56b6625, but as per
discussion with Tom Lane and Álvaro Herrera, a backpatch is preferred to
keep all the branches consistent and to respect the transam's README
where we can.

Author:  Matthias van de Meent, Zhang Mingli
Discussion: https://postgr.es/m/CAEze2WhL8uLMqynnnCu1LAPwxD5RKEo0nHV+eXGg_N6ELU88HQ@mail.gmail.com
Backpatch-through: 10
2022-10-26 09:41:22 +09:00
Amit Kapila 1eed947f98 Add CHECK_FOR_INTERRUPTS while restoring changes during decoding.
Previously in commit 42681dffaf, we added CFI during decoding changes but
missed another similar case that can happen while restoring changes
spilled to disk back into memory in a loop.

Reported-by: Robert Haas
Author: Amit Kapila
Backpatch-through: 10
Discussion: https://postgr.es/m/CA+TgmoaLObg0QbstbC8ykDwOdD1bDkr4AbPpB=0DPgA2JW0mFg@mail.gmail.com
2022-10-21 12:22:47 +05:30
Amit Kapila 38dbaaf273 Fix executing invalidation messages generated by subtransactions during decoding.
This problem has been introduced by commit 272248a0c1 where we started
assigning the subtransactions to the top-level transaction when we mark
both the top-level transaction and its subtransactions as containing
catalog changes. After we assign subtransactions to the top-level
transaction, we were not allowed to execute any invalidations associated
with it when we decide to skip the transaction.

The reason to assign the subtransactions to the top-level transaction was
to avoid the assertion failure in AssertTXNLsnOrder() as they have the
same LSN when we sometimes start accumulating transaction changes for
partial transactions after the restart. Now that with commit 64ff0fe4e8,
we skip this assertion check until we reach the LSN at which we start
decoding the contents of the transaction, so, there is no reason for such
an assignment anymore.

The assignment change was introduced in 15 and prior versions but this bug
doesn't exist in branches prior to 14 since we don't add invalidation
messages to subtransactions. We decided to backpatch through 11 for
consistency but not for 10 since its final release is near.

Reported-by: Kuroda Hayato
Author: Masahiko Sawada
Reviewed-by: Amit Kapila
Backpatch-through: 11
Discussion: https://postgr.es/m/TYAPR01MB58660803BCAA7849C8584AA4F57E9%40TYAPR01MB5866.jpnprd01.prod.outlook.com
Discussion: https://postgr.es/m/a89b46b6-0239-2fd5-71a9-b19b1f7a7145%40enterprisedb.com
2022-10-21 09:42:24 +05:30
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
Thomas Munro cf94cb5866 Track LLVM 15 changes.
Per https://llvm.org/docs/OpaquePointers.html, support for non-opaque
pointers still exists and we can request that on our context.  We have
until LLVM 16 to move to opaque pointers, a much larger change.

Back-patch to 11, where LLVM support arrived.

Author: Thomas Munro <thomas.munro@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAMHz58Sf_xncdyqsekoVsNeKcruKootLtVH6cYXVhhUR1oKPCg%40mail.gmail.com
2022-10-19 22:38:58 +13:00
Tom Lane b21615d1e9 Reject non-ON-SELECT rules that are named "_RETURN".
DefineQueryRewrite() has long required that ON SELECT rules be named
"_RETURN".  But we overlooked the converse case: we should forbid
non-ON-SELECT rules that are named "_RETURN".  In particular this
prevents using CREATE OR REPLACE RULE to overwrite a view's _RETURN
rule with some other kind of rule, thereby breaking the view.

Per bug #17646 from Kui Liu.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/17646-70c93cfa40365776@postgresql.org
2022-10-17 12:14:39 -04:00
Tom Lane 62b263bf77 Guard against table-AM-less relations in planner.
The executor will dump core if it's asked to execute a seqscan on
a relation having no table AM, such as a view.  While that shouldn't
really happen, it's possible to get there via catalog corruption,
such as a missing ON SELECT rule.  It seems worth installing a defense
against that.  There are multiple plausible places for such a defense,
but I picked the planner's get_relation_info().

Per discussion of bug #17646 from Kui Liu.  Back-patch to v12 where
the tableam APIs were introduced; in older versions you won't get a
SIGSEGV, so it seems less pressing.

Discussion: https://postgr.es/m/17646-70c93cfa40365776@postgresql.org
2022-10-17 11:35:23 -04:00
Tom Lane bc7a40b42e Rename parser token REF to REF_P to avoid a symbol conflict.
In the latest version of Apple's macOS SDK, <sys/socket.h>
fails to compile if "REF" is #define'd as something.
Apple may or may not agree that this is a bug, and even if
they do accept the bug report I filed, they probably won't
fix it very quickly.  In the meantime, our back branches will all
fail to compile gram.y.  v15 and HEAD currently escape the problem
thanks to the refactoring done in 98e93a1fc, but that's purely
accidental.  Moreover, since that patch removed a widely-visible
inclusion of <netdb.h>, back-patching it seems too likely to break
third-party code.

Instead, change the token's code name to REF_P, following our usual
convention for naming parser tokens that are likely to have symbol
conflicts.  The effects of that should be localized to the grammar
and immediately surrounding files, so it seems like a safer answer.

Per project policy that we want to keep recently-out-of-support
branches buildable on modern systems, back-patch all the way to 9.2.

Discussion: https://postgr.es/m/1803927.1665938411@sss.pgh.pa.us
2022-10-16 15:27:04 -04:00
Tom Lane 7442701374 Harden pmsignal.c against clobbered shared memory.
The postmaster is not supposed to do anything that depends
fundamentally on shared memory contents, because that creates
the risk that a backend crash that trashes shared memory will
take the postmaster down with it, preventing automatic recovery.
In commit 969d7cd43 I lost sight of this principle and coded
AssignPostmasterChildSlot() in such a way that it could fail
or even crash if the shared PMSignalState structure became
corrupted.  Remarkably, we've not seen field reports of such
crashes; but I managed to induce one while testing the recent
changes around palloc chunk headers.

To fix, make a semi-duplicative state array inside the postmaster
so that we need consult only local state while choosing a "child
slot" for a new backend.  Ensure that other postmaster-executed
routines in pmsignal.c don't have critical dependencies on the
shared state, either.  Corruption of PMSignalState might now
lead ReleasePostmasterChildSlot() to conclude that backend X
failed, when actually backend Y was the one that trashed things.
But that doesn't matter, because we'll force a cluster-wide reset
regardless.

Back-patch to all supported branches, since this is an old bug.

Discussion: https://postgr.es/m/3436789.1665187055@sss.pgh.pa.us
2022-10-11 18:54:31 -04:00
Tom Lane 21e042b0bd Yet further fixes for multi-row VALUES lists for updatable views.
DEFAULT markers appearing in an INSERT on an updatable view
could be mis-processed if they were in a multi-row VALUES clause.
This would lead to strange errors such as "cache lookup failed
for type NNNN", or in older branches even to crashes.

The cause is that commit 41531e42d tried to re-use rewriteValuesRTE()
to remove any SetToDefault nodes (that hadn't previously been replaced
by the view's own default values) appearing in "product" queries,
that is DO ALSO queries.  That's fundamentally wrong because the
DO ALSO queries might not even be INSERTs; and even if they are,
their targetlists don't necessarily match the view's column list,
so that almost all the logic in rewriteValuesRTE() is inapplicable.

What we want is a narrow focus on replacing any such nodes with NULL
constants.  (That is, in this context we are interpreting the defaults
as being strictly those of the view itself; and we already replaced
any that aren't NULL.)  We could add still more !force_nulls tests
to further lobotomize rewriteValuesRTE(); but it seems cleaner to
split out this case to a new function, restoring rewriteValuesRTE()
to the charter it had before.

Per bug #17633 from jiye_sw.  Patch by me, but thanks to
Richard Guo and Japin Li for initial investigation.
Back-patch to all supported branches, as the previous fix was.

Discussion: https://postgr.es/m/17633-98cc85e1fa91e905@postgresql.org
2022-10-11 18:24:14 -04:00
Alvaro Herrera 7d520e68ea
Fix self-referencing foreign keys with partitioned tables
There are a number of bugs in this area.  Two of them are fixed here,
namely:
1. get_relation_idx_constraint_oid does not restrict the type of
   constraint that's returned, so with sufficient bad luck it can
   return the OID of a foreign key constraint.  This has the effect that
   a primary key in a partition can end up as a child of a foreign key,
   which makes no sense (it needs to be the child of the equivalent
   primary key.)
   Change the API contract so that only index-backed constraints are
   returned, mimicking get_constraint_index().

2. Both CloneFkReferenced and CloneFkReferencing clone a
   self-referencing foreign key, so the partition ends up with
   a duplicate foreign key.  Change the former function to ignore such
   constraints.

Add some tests to verify that things are better now.  (However, these
new tests show some additional misbehavior that will be fixed later --
namely that there's a constraint marked NOT VALID.)

Backpatch to 12, where these constraints are possible at all.

Author: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Discussion: https://postgr.es/m/20220603154232.1715b14c@karst
2022-10-07 19:37:48 +02:00
Tom Lane 92941f2643 Avoid improbable PANIC during heap_update, redux.
Commit 34f581c39 intended to ensure that RelationGetBufferForTuple
would acquire a visibility-map page pin in case the otherBuffer's
all-visible bit had become set since we last had lock on that page.
But I missed a case: when we're extending the relation, VM concerns
were dealt with only in the relatively-less-likely case that we
fail to conditionally lock the otherBuffer.  I think I'd believed
that we couldn't need to worry about it if the conditional lock
succeeds, which is true for the target buffer; but the otherBuffer
was unlocked for awhile so its bit might be set anyway.  So we need
to do the GetVisibilityMapPins dance, and then also recheck the
page's free space, in both cases.

Per report from Jaime Casanova.  Back-patch to v12 as the previous
patch was (although there's still no evidence that the bug is
reachable pre-v14).

Discussion: https://postgr.es/m/E1lWLjP-00006Y-Ml@gemulon.postgresql.org
2022-09-30 19:36:46 -04:00
Alvaro Herrera 1dd468c348
Change some errdetail() to errdetail_internal()
This prevents marking the argument string for translation for gettext,
and it also prevents the given string (which is already translated) from
being translated at runtime.

Also, mark the strings used as arguments to check_rolespec_name for
translation.

Backpatch all the way back as appropriate.  None of this is caught by
any tests (necessarily so), so I verified it manually.
2022-09-28 17:14:53 +02:00
Tom Lane 8c17c86154 Fix tupdesc lifespan bug with AfterTriggersTableData.storeslot.
Commit 25936fd46 adjusted things so that the "storeslot" we use
for remapping trigger tuples would have adequate lifespan, but it
neglected to consider the lifespan of the tuple descriptor that
the slot depends on.  It turns out that in at least some cases, the
tupdesc we are passing is a refcounted tupdesc, and the refcount for
the slot's reference can get assigned to a resource owner having
different lifespan than the slot does.  That leads to an error like
"tupdesc reference 0x7fdef236a1b8 is not owned by resource owner
SubTransaction".  Worse, because of a second oversight in the same
commit, we'd try to free the same tupdesc refcount again while
cleaning up after that error, leading to recursive errors and an
"ERRORDATA_STACK_SIZE exceeded" PANIC.

To fix the initial problem, let's just make a non-refcounted copy
of the tupdesc we're supposed to use.  That seems likely to guard
against additional problems, since there's no strong reason for
this code to assume that what it's given is a refcounted tupdesc;
in which case there's an independent hazard of the tupdesc having
shorter lifespan than the slot does.  (I didn't bother trying to
free said copy, since it should go away anyway when the (sub)
transaction context is cleaned up.)

The other issue can be fixed by making the code added to
AfterTriggerFreeQuery work like the rest of that function, ie be
sure that it doesn't try to free the same slot twice in the event
of recursive error cleanup.

While here, also clean up minor stylistic issues in the test case
added by 25936fd46: don't use "create or replace function", as any
name collision within the tests is likely to have ill effects
that that won't mask; and don't use function names as generic as
trigger_function1, especially if you're not going to drop them
at the end of the test stanza.

Per bug #17607 from Thomas Mc Kay.  Back-patch to v12, as the
previous fix was.

Discussion: https://postgr.es/m/17607-bd8ccc81226f7f80@postgresql.org
2022-09-25 17:10:58 -04:00
Jeff Davis 410c422b75 Fix race condition where heap_delete() fails to pin VM page.
Similar to 5f12bc94dc, the code must re-check PageIsAllVisible() after
buffer lock is re-acquired. Backpatching to the same version, 12.

Discussion: https://postgr.es/m/CAEP4nAw9jYQDKd_5Y+-s2E4YiUJq1vqiikFjYGpLShtp-K3gag@mail.gmail.com
Reported-by: Robins Tharakan
Reviewed-by: Robins Tharakan
Backpatch-through: 12
2022-09-22 11:06:42 -07:00
Etsuro Fujita 5f9dda4c06 Fix thinko in comment.
This comment has been wrong since its introduction in commit 0d5f05cde;
backpatch to v12 where that came in.

Discussion: https://postgr.es/m/CAPmGK14VGf-xQjGQN4o1QyAbXAaxugU5%3DqfcmTDh1iufUDnV_w%40mail.gmail.com
2022-09-22 15:55:05 +09:00
Tom Lane db8e36682d Suppress more variable-set-but-not-used warnings from clang 15.
Mop up assorted set-but-not-used warnings in the back branches.
This includes back-patching relevant fixes from commit 152c9f7b8
the rest of the way, but there are also several cases that did not
appear in HEAD.  Some of those we'd fixed in a retail way but not
back-patched, and others I think just got rewritten out of existence
during nearby refactoring.

While here, also back-patch b1980f6d0 (PL/Tcl: Fix compiler warnings
with Tcl 8.6) into 9.2, so that that branch compiles warning-free
with modern Tcl.

Per project policy, this is a candidate for back-patching into
out-of-support branches: it suppresses annoying compiler warnings
but changes no behavior.  Hence, back-patch all the way to 9.2.

Discussion: https://postgr.es/m/514615.1663615243@sss.pgh.pa.us
2022-09-21 13:52:38 -04:00
Tom Lane ca3b730baa Suppress variable-set-but-not-used warnings from clang 15.
clang 15+ will issue a set-but-not-used warning when the only
use of a variable is in autoincrements (e.g., "foo++;").
That's perfectly sensible, but it detects a few more cases that
we'd not noticed before.  Silence the warnings with our usual
methods, such as PG_USED_FOR_ASSERTS_ONLY, or in one case by
actually removing a useless variable.

One thing that we can't nicely get rid of is that with %pure-parser,
Bison emits "yynerrs" as a local variable that falls foul of this
warning.  To silence those, I inserted "(void) yynerrs;" in the
top-level productions of affected grammars.

Per recently-established project policy, this is a candidate
for back-patching into out-of-support branches: it suppresses
annoying compiler warnings but changes no behavior.  Hence,
back-patch to 9.5, which is as far as these patches go without
issues.  (A preliminary check shows that the prior branches
need some other set-but-not-used cleanups too, so I'll leave
them for another day.)

Discussion: https://postgr.es/m/514615.1663615243@sss.pgh.pa.us
2022-09-20 12:04:37 -04:00
Tom Lane c58513f095 Future-proof the recursion inside ExecShutdownNode().
The API contract for planstate_tree_walker() callbacks is that they
take a PlanState pointer and a context pointer.  Somebody figured
they could save a couple lines of code by ignoring that, and passing
ExecShutdownNode itself as the walker even though it has but one
argument.  Somewhat remarkably, we've gotten away with that so far.
However, it seems clear that the upcoming C2x standard means to
forbid such cases, and compilers that actively break such code
likely won't be far behind.  So spend the extra few lines of code
to do it honestly with a separate walker function.

In HEAD, we might as well go further and remove ExecShutdownNode's
useless return value.  I left that as-is in back branches though,
to forestall complaints about ABI breakage.

Back-patch, with the thought that this might become of practical
importance before our stable branches are all out of service.
It doesn't seem to be fixing any live bug on any currently known
platform, however.

Discussion: https://postgr.es/m/208054.1663534665@sss.pgh.pa.us
2022-09-19 12:16:02 -04:00
Daniel Gustafsson eb8b848079 Fix NaN comparison in circle_same test
Commit c4c340088 changed geometric operators to use float4 and float8
functions, and handle NaN's in a better way. The circle sameness test
had a typo in the code which resulted in all comparisons with the left
circle having a NaN radius considered same.

  postgres=# select '<(0,0),NaN>'::circle ~= '<(0,0),1>'::circle;
  ?column?
  ----------
  t
  (1 row)

This fixes the sameness test to consider the radius of both the left
and right circle.

Backpatch to v12 where this was introduced.

Author: Ranier Vilela <ranier.vf@gmail.com>
Discussion: https://postgr.es/m/CAEudQAo8dK=yctg2ZzjJuzV4zgOPBxRU5+Kb+yatFiddtQk6Rw@mail.gmail.com
Backpatch-through: v12
2022-09-12 12:59:06 +02:00
Alvaro Herrera 80ef25b1ad
Choose FK name correctly during partition attachment
During ALTER TABLE ATTACH PARTITION, if the name of a parent's foreign
key constraint is already used on the partition, the code tries to
choose another one before the FK attributes list has been populated,
so the resulting constraint name was "<relname>__fkey" instead of
"<relname>_<attrs>_fkey".  Repair, and add a test case.

Backpatch to 12.  In 11, the code to attach a partition was not smart
enough to cope with conflicting constraint names, so the problem doesn't
exist there.

Author: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Discussion: https://postgr.es/m/20220901184156.738ebee5@karst
2022-09-08 13:17:02 +02:00
Tom Lane ccbb54c729 Further fixes for MULTIEXPR_SUBLINK fix.
Some more things I didn't think about in commits 3f7323cbb et al:

MULTIEXPR_SUBLINK subplans might have been converted to initplans
instead of regular subplans, in which case they won't show up in
the modified targetlist.  Fortunately, this would only happen if
they have no input parameters, which means that the problem we
originally needed to fix can't happen with them.  Therefore, there's
no need to clone their output parameters, and thus it doesn't hurt
that we'll fail to see them in the first pass over the targetlist.
Nonetheless, this complicates matters greatly, because now we have
to distinguish output Params of initplans (which shouldn't get
renumbered) from those of regular subplans (which should).
This also breaks the simplistic scheme I used of assuming that the
subplans found in the targetlist have consecutive subLinkIds.
We really can't avoid the need to know the subplans' subLinkIds in
this code.  To fix that, add subLinkId as the last field of SubPlan.
We can get away with that change in back branches because SubPlan
nodes will never be stored in the catalogs, and there's no ABI
break for external code that might be looking at the existing
fields of SubPlan.

Secondly, rewriteTargetListIU might have rolled up multiple
FieldStores or SubscriptingRefs into one targetlist entry,
breaking the assumption that there's at most one Param to fix
per targetlist entry.  (That assumption is OK I think in the
ruleutils.c code I stole the logic from in 18f51083c, because
that only deals with pre-rewrite query trees.  But it's
definitely not OK here.)  Abandon that shortcut and just do a
full tree walk on the targetlist to ensure we find all the
Params we have to change.

Per bug #17606 from Andre Lin.  As before, only v10-v13 need the
patch.

Discussion: https://postgr.es/m/17606-e5c8ad18d31db96a@postgresql.org
2022-09-06 16:38:18 -04:00
Peter Geoghegan 43e409cea4 Backpatch nbtree page deletion hardening.
Postgres 14 commit 5b861baa taught nbtree VACUUM to tolerate buggy
opclasses.  VACUUM's inability to locate a to-be-deleted page's downlink
in the parent page was logged instead of throwing an error.  VACUUM
could just press on with vacuuming the index, and vacuuming the table as
a whole.

There are now anecdotal reports of this error causing problems that were
much more disruptive than the underlying index corruption ever could be.
Anything that makes VACUUM unable to make forward progress against one
table/index ultimately risks making the system enter xidStopLimit mode.
There is no good reason to take any chances here, so backpatch the
hardening commit.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wzm9HR6Pow=t-iQa57zT8qmX6_M4h14F-pTtb=xFDW5FBA@mail.gmail.com
Backpatch: 10-13 (all supported versions that lacked the hardening)
2022-09-05 11:20:05 -07:00
Tom Lane 18f51083c9 Fix oversight in recent MULTIEXPR_SUBLINK fix.
Commits 3f7323cbb et al missed the possibility that the Params
they are looking for could be buried under implicit coercions,
as well as other stuff that processIndirection() could add to
the original targetlist entry.  Copy the code in ruleutils.c
that deals with such cases.  (I thought about refactoring so
that there's just one copy; but seeing that we only need this
in old back branches, it seems not worth the trouble.)

Per off-list report from Andre Lin.  As before, only v10-v13
need the patch.

Discussion: https://postgr.es/m/17596-c5357f61427a81dc@postgresql.org
2022-09-02 14:54:40 -04:00
David Rowley 210bece161 Fix some possibly latent bugs in slab.c
Primarily, this fixes an incorrect calculation in SlabCheck which was
looking in the wrong byte for the sentinel check.  The reason that we've
never noticed this before in the form of a failing sentinel check is
because the pre-check to this always fails because all current core users
of slab contexts have a chunk size which is already MAXALIGNed, therefore
there's never any space for the sentinel byte.  It is possible that an
extension needs to use a slab context and if they do with a chunk size
that's not MAXALIGNed, then they'll likely get errors about overwritten
sentinel bytes.

Additionally, this patch changes various calculations which are being done
based on the sizeof(SlabBlock).  Currently, sizeof(SlabBlock) is a
multiple of 8, therefore sizeof(SlabBlock) is the same as
MAXALIGN(sizeof(SlabBlock)), however, if we were to ever have to add any
fields to that struct as part of a bug fix, then SlabAlloc could end up
returning a non-MAXALIGNed pointer.  To be safe, let's ensure we always
MAXALIGN sizeof(SlabBlock) before using it in any calculations.

This patch has already been applied to master in d5ee4db0e.

Diagnosed-by: Tomas Vondra, Tom Lane
Author: Tomas Vondra, David Rowley
Discussion: https://postgr.es/m/CAA4eK1%2B1JyW5TiL%3DyV-3Uq1CrfnTyn0Xrk5uArt31Z%3D8rgPhXQ%40mail.gmail.com
Backpatch-through: 10
2022-09-01 19:23:08 +12:00
Tom Lane 45f7152b9b Prevent long-term memory leakage in autovacuum launcher.
get_database_list() failed to restore the caller's memory context,
instead leaving current context set to TopMemoryContext which is
how CommitTransactionCommand() leaves it.  The callers both think
they are using short-lived contexts, for the express purpose of
not having to worry about cleaning up individual allocations.
The net effect therefore is that supposedly short-lived allocations
could accumulate indefinitely in the launcher's TopMemoryContext.

Although this has been broken for a long time, it seems we didn't
have any obvious memory leak here until v15's rearrangement of the
stats logic.  I (tgl) am not entirely convinced that there's no
other leak at all, though, and we're surely at risk of adding one
in future back-patched fixes.  So back-patch to all supported
branches, even though this may be only a latent bug in pre-v15.

Reid Thompson

Discussion: https://postgr.es/m/972a4e12b68b0f96db514777a150ceef7dcd2e0f.camel@crunchydata.com
2022-08-31 16:23:20 -04:00
Tom Lane f204ad3a2b In the Snowball dictionary, don't try to stem excessively-long words.
If the input word exceeds 1000 bytes, don't pass it to the stemmer;
just return it as-is after case folding.  Such an input is surely
not a word in any human language, so whatever the stemmer might
do to it would be pretty dubious in the first place.  Adding this
restriction protects us against a known recursion-to-stack-overflow
problem in the Turkish stemmer, and it seems like good insurance
against any other safety or performance issues that may exist in
the Snowball stemmers.  (I note, for example, that they contain no
CHECK_FOR_INTERRUPTS calls, so we really don't want them running
for a long time.)  The threshold of 1000 bytes is arbitrary.

An alternative definition could have been to treat such words as
stopwords, but that seems like a bigger break from the old behavior.

Per report from Egor Chindyaskin and Alexander Lakhin.
Thanks to Olly Betts for the recommendation to fix it this way.

Discussion: https://postgr.es/m/1661334672.728714027@f473.i.mail.ru
2022-08-31 10:42:05 -04:00
Robert Haas 3f2701cda5 Prevent WAL corruption after a standby promotion.
When a PostgreSQL instance performing archive recovery but not using
standby mode is promoted, and the last WAL segment that it attempted
to read ended in a partial record, the previous code would create
invalid WAL on the new timeline. The WAL from the previously timeline
would be copied to the new timeline up until the end of the last valid
record, but instead of beginning to write WAL at immediately
afterwards, the promoted server would write an overwrite contrecord at
the beginning of the next segment. The end of the previous segment
would be left as all-zeroes, resulting in failures if anything tried
to read WAL from that file.

The root of the issue is that ReadRecord() decides whether to set
abortedRecPtr and missingContrecPtr based on the value of StandbyMode,
but ReadRecord() switches to a new timeline based on the value of
ArchiveRecoveryRequested. We shouldn't try to write an overwrite
contrecord if we're switching to a new timeline, so change the test in
ReadRecod() to check ArchiveRecoveryRequested instead.

Code fix by Dilip Kumar. Comments by me incorporating suggested
language from Álvaro Herrera. Further review from Kyotaro Horiguchi
and Sami Imseih.

Discussion: http://postgr.es/m/CAFiTN-t7umki=PK8dT1tcPV=mOUe2vNhHML6b3T7W7qqvvajjg@mail.gmail.com
Discussion: http://postgr.es/m/FB0DEA0B-E14E-43A0-811F-C1AE93D00FF3%40amazon.com
2022-08-29 11:30:17 -04:00
Tom Lane 3f7323cbbd Repair rare failure of MULTIEXPR_SUBLINK subplans in inherited updates.
Prior to v14, if we have a MULTIEXPR SubPlan (that is, use of the syntax
UPDATE ... SET (c1, ...) = (SELECT ...)) in an UPDATE with an inherited
or partitioned target table, inheritance_planner() will clone the
targetlist and therefore also the MULTIEXPR SubPlan and the Param nodes
referencing it for each child target table.  Up to now, we've allowed
all the clones to share the underlying subplan as well as the output
parameter IDs -- that is, the runtime ParamExecData slots.  That
technique is borrowed from the far older code that supports initplans,
and it works okay in that case because the cloned SubPlan nodes are
essentially identical.  So it doesn't matter which one of the clones
the shared ParamExecData.execPlan field might point to.

However, this fails to hold for MULTIEXPR SubPlans, because they can
have nonempty "args" lists (values to be passed into the subplan), and
those lists could get mutated to different states in the various clones.
In the submitted reproducer, as well as the test case added here, one
clone contains Vars with varno OUTER_VAR where another has INNER_VAR,
because the child tables are respectively on the outer or inner side of
the join.  Sharing the execPlan pointer can result in trying to evaluate
an args list that doesn't match the local execution state, with mayhem
ensuing.  The result often is to trigger consistency checks in the
executor, but I believe this could end in a crash or incorrect updates.

To fix, assign new Param IDs to each of the cloned SubPlans, so that
they don't share ParamExecData slots at runtime.  It still seems fine
for the clones to share the underlying subplan, and extra ParamExecData
slots are cheap enough that this fix shouldn't cost much.

This has been busted since we invented MULTIEXPR SubPlans in 9.5.
Probably the lack of previous reports is because query plans in which
the different clones of a MULTIEXPR mutate to effectively-different
states are pretty rare.  There's no issue in v14 and later, because
without inheritance_planner() there's never a reason to clone
MULTIEXPR SubPlans.

Per bug #17596 from Andre Lin.  Patch v10-v13 only.

Discussion: https://postgr.es/m/17596-c5357f61427a81dc@postgresql.org
2022-08-27 12:11:20 -04:00
Etsuro Fujita 7d50165755 Fix typo in comment. 2022-08-26 16:55:04 +09:00
Tom Lane 2d1f1523ce Defend against stack overrun in a few more places.
SplitToVariants() in the ispell code, lseg_inside_poly() in geo_ops.c,
and regex_selectivity_sub() in selectivity estimation could recurse
until stack overflow; fix by adding check_stack_depth() calls.
So could next() in the regex compiler, but that case is better fixed by
converting its tail recursion to a loop.  (We probably get better code
that way too, since next() can now be inlined into its sole caller.)

There remains a reachable stack overrun in the Turkish stemmer, but
we'll need some advice from the Snowball people about how to fix that.

Per report from Egor Chindyaskin and Alexander Lakhin.  These mistakes
are old, so back-patch to all supported branches.

Richard Guo and Tom Lane

Discussion: https://postgr.es/m/1661334672.728714027@f473.i.mail.ru
2022-08-24 13:01:40 -04:00
Tom Lane 384497f34d Doc: prefer sysctl to /proc/sys in docs and comments.
sysctl is more portable than Linux's /proc/sys file tree, and
often easier to use too.  That's why most of our docs refer to
sysctl when talking about how to adjust kernel parameters.
Bring the few stragglers into line.

Discussion: https://postgr.es/m/361175.1661187463@sss.pgh.pa.us
2022-08-23 09:42:10 -04:00
Amit Kapila 4985a45917 Add CHECK_FOR_INTERRUPTS while decoding changes.
While decoding changes in a loop, if we skip all the changes there is no
CFI making the loop uninterruptible.

Reported-by: Whale Song and Andrey Borodin
Bug: 17580
Author: Masahiko Sawada
Reviwed-by: Amit Kapila
Backpatch-through: 10
Discussion: https://postgr.es/m/17580-849c1d5b6d7eb422@postgresql.org
Discussion: https://postgr.es/m/B319ECD6-9A28-4CDF-A8F4-3591E0BF2369@yandex-team.ru
2022-08-23 09:10:28 +05:30
Tom Lane 9f0073ef7d Fix subtly-incorrect matching of parent and child partitioned indexes.
When creating a partitioned index, DefineIndex tries to identify
any existing indexes on the partitions that match the partitioned
index, so that it can absorb those as child indexes instead of
building new ones.  Part of the matching is to compare IndexInfo
structs --- but that wasn't done quite right.  We're comparing
the IndexInfo built within DefineIndex itself to one made from
existing catalog contents by BuildIndexInfo.  Notably, while
BuildIndexInfo will run index expressions and predicates through
expression preprocessing, that has not happened to DefineIndex's
struct.  The result is failure to match and subsequent creation
of duplicate indexes.

The easiest and most bulletproof fix is to build a new IndexInfo
using BuildIndexInfo, thereby guaranteeing that the processing done
is identical.

While here, let's also extract the opfamily and collation data
from the new partitioned index, removing ad-hoc logic that
duplicated knowledge about how those are constructed.

Per report from Christophe Pettus.  Back-patch to v11 where
we invented partitioned indexes.

Richard Guo and Tom Lane

Discussion: https://postgr.es/m/8864BFAA-81FD-4BF9-8E06-7DEB8D4164ED@thebuild.com
2022-08-18 12:11:47 -04:00
Amit Kapila 1df86aac51 Fix replica identity check for a partitioned table.
The current publisher code checks if UPDATE or DELETE can be executed with
the replica identity of the table even if it's a partitioned table. We can
skip checking the replica identity for partitioned tables because the
operations are actually performed on the leaf partitions (not the
partitioned table).

Reported-by: Brad Nicholson
Author: Hou Zhijie
Reviewed-by: Peter Smith, Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/CAMMnM%3D8i5DohH%3DYKzV0_wYuYSYvuOJoL9F5nzXTc%2ByzsG1f6rg%40mail.gmail.com
2022-08-16 14:30:27 +05:30
Michael Paquier bcf7eb99bb Fix outdated --help message for postgres -f
This option switch supports a total of 8 values, as told by
set_plan_disabling_options() and the documentation, but this was not
reflected in the output generated by --help.

Author: Junwang Zhao
Discussion: https://postgr.es/m/CAEG8a3+pT3cWzyjzKs184L1XMNm8NDnoJLiSjAYSO7XqpRh_vA@mail.gmail.com
Backpatch-through: 10
2022-08-15 13:37:40 +09:00
Tom Lane 9fe285f859 Preserve memory context of VarStringSortSupport buffers.
When enlarging the work buffers of a VarStringSortSupport object,
varstrfastcmp_locale was careful to keep them in the ssup_cxt
memory context; but varstr_abbrev_convert just used palloc().
The latter creates a hazard that the buffers could be freed out
from under the VarStringSortSupport object, resulting in stomping
on whatever gets allocated in that memory later.

In practice, because we only use this code for ICU collations
(cf. 3df9c374e), the problem is confined to use of ICU collations.
I believe it may have been unreachable before the introduction
of incremental sort, too, as traditional sorting usually just
uses one context for the duration of the sort.

We could fix this by making the broken stanzas in varstr_abbrev_convert
match the non-broken ones in varstrfastcmp_locale.  However, it seems
like a better idea to dodge the issue altogether by replacing the
pfree-and-allocate-anew coding with repalloc, which automatically
preserves the chunk's memory context.  This fix does add a few cycles
because repalloc will copy the chunk's content, which the existing
coding assumes is useless.  However, we don't expect that these buffer
enlargement operations are performance-critical.  Besides that, it's
far from obvious that copying the buffer contents isn't required, since
these stanzas make no effort to mark the buffers invalid by resetting
last_returned, cache_blob, etc.  That seems to be safe upon examination,
but it's fragile and could easily get broken in future, which wouldn't
get revealed in testing with short-to-moderate-size strings.

Per bug #17584 from James Inform.  Whether or not the issue is
reachable in the older branches, this code has been broken on its
own terms from its introduction, so patch all the way back.

Discussion: https://postgr.es/m/17584-95c79b4a7d771f44@postgresql.org
2022-08-14 12:05:27 -04:00
Tom Lane 4878ea717c Avoid misbehavior when hash_table_bytes < bucket_size.
It's possible to reach this case when work_mem is very small and tupsize
is (relatively) very large.  In that case ExecChooseHashTableSize would
get an assertion failure, or with asserts off it'd compute nbuckets = 0,
which'd likely cause misbehavior later (I've not checked).  To fix,
clamp the number of buckets to be at least 1.

This is due to faulty conversion of old my_log2() coding in 28d936031.
Back-patch to v13, as that was.

Zhang Mingli

Discussion: https://postgr.es/m/beb64ca0-91e2-44ac-bf4a-7ea36275ec02@Spark
2022-08-13 16:59:58 -04:00
Tom Lane 60f876317e Catch stack overflow when recursing in transformFromClauseItem().
Most parts of the parser can expect that the stack overflow check
in transformExprRecurse() will trigger before things get desperate.
However, transformFromClauseItem() can recurse directly to self
without having analyzed any expressions, so it's possible to drive
it to a stack-overrun crash.  Add a check to prevent that.

Per bug #17583 from Egor Chindyaskin.  Back-patch to all supported
branches.

Richard Guo

Discussion: https://postgr.es/m/17583-33be55b9f981f75c@postgresql.org
2022-08-13 15:21:28 -04:00
Peter Eisentraut 8b2638fdd4 Add missing fields to _outConstraint()
As of 897795240c, check constraints can
be declared invalid.  But that patch didn't update _outConstraint() to
also show the relevant struct fields (which were only applicable to
foreign keys before that).  This currently only affects debugging
output, so no impact in practice.
2022-08-13 10:37:53 +02:00
Peter Eisentraut f70dfbf36f Fix _outConstraint() for "identity" constraints
The set of fields printed by _outConstraint() in the CONSTR_IDENTITY
case didn't match the set of fields actually used in that case.  (The
code was probably uncarefully copied from the CONSTR_DEFAULT case.)
Fix that by using the right set of fields.  Since there is no read
support for this node type, this is really just for debugging output
right now, so it doesn't affect anything important.
2022-08-12 08:52:38 +02:00
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 71caf3c4da Fix handling of R/W expanded datums that are passed to SQL functions.
fmgr_sql must make expanded-datum arguments read-only, because
it's possible that the function body will pass the argument to
more than one callee function.  If one of those functions takes
the datum's R/W property as license to scribble on it, then later
callees will see an unexpected value, leading to wrong answers.

From a performance standpoint, it'd be nice to skip this in the
common case that the argument value is passed to only one callee.
However, detecting that seems fairly hard, and certainly not
something that I care to attempt in a back-patched bug fix.

Per report from Adam Mackler.  This has been broken since we
invented expanded datums, so back-patch to all supported branches.

Discussion: https://postgr.es/m/WScDU5qfoZ7PB2gXwNqwGGgDPmWzz08VdydcPFLhOwUKZcdWbblbo-0Lku-qhuEiZoXJ82jpiQU4hOjOcrevYEDeoAvz6nR0IU4IHhXnaCA=@mackler.email
Discussion: https://postgr.es/m/187436.1660143060@sss.pgh.pa.us
2022-08-10 13:37:25 -04:00
Tom Lane 7e92f78abe In extensions, don't replace objects not belonging to the extension.
Previously, if an extension script did CREATE OR REPLACE and there was
an existing object not belonging to the extension, it would overwrite
the object and adopt it into the extension.  This is problematic, first
because the overwrite is probably unintentional, and second because we
didn't change the object's ownership.  Thus a hostile user could create
an object in advance of an expected CREATE EXTENSION command, and would
then have ownership rights on an extension object, which could be
modified for trojan-horse-type attacks.

Hence, forbid CREATE OR REPLACE of an existing object unless it already
belongs to the extension.  (Note that we've always forbidden replacing
an object that belongs to some other extension; only the behavior for
previously-free-standing objects changes here.)

For the same reason, also fail CREATE IF NOT EXISTS when there is
an existing object that doesn't belong to the extension.

Our thanks to Sven Klemm for reporting this problem.

Security: CVE-2022-2625
2022-08-08 11:12:31 -04:00
Alvaro Herrera 330c48b284
Translation updates
Source-Git-URL: ssh://git@git.postgresql.org/pgtranslation/messages.git
Source-Git-Hash: 8ee19d25e0753a690bea62ddcbbfaf2e0d093c1d
2022-08-08 12:39:52 +02:00
Tom Lane 476f9d5330 Partially undo commit 94da73281.
On closer inspection, mcv.c isn't as broken for ScalarArrayOpExpr
as I thought.  The Var-on-right issue is real enough, but actually
it does cope fine with a NULL array constant --- I was misled by
an XXX comment suggesting it didn't.  Undo that part of the code
change, and replace the XXX comment with something less misleading.
2022-08-05 15:57:46 -04:00
Tom Lane c102d11067 Fix non-bulletproof ScalarArrayOpExpr code for extended statistics.
statext_is_compatible_clause_internal() checked that the arguments
of a ScalarArrayOpExpr are one Var and one Const, but it would allow
cases where the Const was on the left.  Subsequent uses of the clause
are not expecting that and would suffer assertion failures or core
dumps.  mcv.c also had not bothered to cope with the case of a NULL
array constant, which seems really unacceptably sloppy of somebody.
(Although our tools failed us there too, since AFAIK neither Coverity
nor any compiler warned of the obvious use-of-uninitialized-variable
condition.)  It seems best to handle that by having
statext_is_compatible_clause_internal() reject it.

Noted while fixing bug #17570.  Back-patch to v13 where the
extended stats code grew some awareness of ScalarArrayOpExpr.
2022-08-05 13:58:49 -04:00
Alvaro Herrera de31e6f81e
BRIN: mask BRIN_EVACUATE_PAGE for WAL consistency checking
That bit is unlogged and therefore it's wrong to consider it in WAL page
comparison.

Add a test that tickles the case, as branch testing technology allows.

This has been a problem ever since wal consistency checking was
introduced (commit a507b86900 for pg10), so backpatch to all supported
branches.

Author: 王海洋 (Haiyang Wang) <wanghaiyang.001@bytedance.com>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/CACciXAD2UvLMOhc4jX9VvOKt7DtYLr3OYRBhvOZ-jRxtzc_7Jg@mail.gmail.com
Discussion: https://postgr.es/m/CACciXADOfErX9Bx0nzE_SkdfXr6Bbpo5R=v_B6MUTEYW4ya+cg@mail.gmail.com
2022-08-05 18:00:17 +02:00
Noah Misch ad8ebcfe96 Add HINT for restartpoint race with KeepFileRestoredFromArchive().
The five commits ending at cc2c7d65fc
closed this race condition for v15+.  For v14 through v10, add a HINT to
discourage studying the cosmetic problem.

Reviewed by Kyotaro Horiguchi and David Steele.

Discussion: https://postgr.es/m/20220731061747.GA3692882@rfd.leadboat.com
2022-08-05 08:31:01 -07:00
Alvaro Herrera ab85566301
Fix ENABLE/DISABLE TRIGGER to handle recursion correctly
Using ATSimpleRecursion() in ATPrepCmd() to do so as bbb927b4db did is
not correct, because ATPrepCmd() can't distinguish between triggers that
may be cloned and those that may not, so would wrongly try to recurse
for the latter category of triggers.

So this commit restores the code in EnableDisableTrigger() that
86f575948c had added to do the recursion, which would do it only for
triggers that may be cloned, that is, row-level triggers.  This also
changes tablecmds.c such that ATExecCmd() is able to pass the value of
ONLY flag down to EnableDisableTrigger() using its new 'recurse'
parameter.

This also fixes what seems like an oversight of 86f575948c that the
recursion to partition triggers would only occur if EnableDisableTrigger()
had actually changed the trigger.  It is more apt to recurse to inspect
partition triggers even if the parent's trigger didn't need to be
changed: only then can we be certain that all descendants share the same
state afterwards.

Backpatch all the way back to 11, like bbb927b4db.  Care is taken not
to break ABI compatibility (and that no catversion bump is needed.)

Co-authored-by: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Dmitry Koval <d.koval@postgrespro.ru>
Discussion: https://postgr.es/m/CA+HiwqG-cZT3XzGAnEgZQLoQbyfJApVwOTQaCaas1mhpf+4V5A@mail.gmail.com
2022-08-05 09:47:06 +02:00
Tom Lane 23edf0e8b4 Add CHECK_FOR_INTERRUPTS in ExecInsert's speculative insertion loop.
Ordinarily the functions called in this loop ought to have plenty
of CFIs themselves; but we've now seen a case where no such CFI is
reached, making the loop uninterruptible.  Even though that's from
a recently-introduced bug, it seems prudent to install a CFI at
the loop level in all branches.

Per discussion of bug #17558 from Andrew Kesper (an actual fix for
that bug will follow).

Discussion: https://postgr.es/m/17558-3f6599ffcf52fd4a@postgresql.org
2022-08-04 14:10:06 -04:00
Tom Lane da4ed75881 Fix incorrect tests for SRFs in relation_can_be_sorted_early().
Commit fac1b470a thought we could check for set-returning functions
by testing only the top-level node in an expression tree.  This is
wrong in itself, and to make matters worse it encouraged others
to make the same mistake, by exporting tlist.c's special-purpose
IS_SRF_CALL() as a widely-visible macro.  I can't find any evidence
that anyone's taken the bait, but it was only a matter of time.

Use expression_returns_set() instead, and stuff the IS_SRF_CALL()
genie back in its bottle, this time with a warning label.  I also
added a couple of cross-reference comments.

After a fair amount of fooling around, I've despaired of making
a robust test case that exposes the bug reliably, so no test case
here.  (Note that the test case added by fac1b470a is itself
broken, in that it doesn't notice if you remove the code change.
The repro given by the bug submitter currently doesn't fail either
in v15 or HEAD, though I suspect that may indicate an unrelated bug.)

Per bug #17564 from Martijn van Oosterhout.  Back-patch to v13,
as the faulty patch was.

Discussion: https://postgr.es/m/17564-c7472c2f90ef2da3@postgresql.org
2022-08-03 17:33:42 -04:00
Tom Lane 331f8b851c Check maximum number of columns in function RTEs, too.
I thought commit fd96d14d9 had plugged all the holes of this sort,
but no, function RTEs could produce oversize tuples too, either
via long coldeflists or just from multiple functions in one RTE.
(I'm pretty sure the other variants of base RTEs aren't a problem,
because they ultimately refer to either a table or a sub-SELECT,
whose widths are enforced elsewhere.  But we explicitly allow join
RTEs to be overwidth, as long as you don't try to form their
tuple result.)

Per further discussion of bug #17561.  As before, patch all branches.

Discussion: https://postgr.es/m/17561-80350151b9ad2ad4@postgresql.org
2022-08-01 12:22:35 -04:00
Tom Lane ba2002d02c In transformRowExpr(), check for too many columns in the row.
A RowExpr with more than MaxTupleAttributeNumber columns would fail at
execution anyway, since we cannot form a tuple datum with more than that
many columns.  While heap_form_tuple() has a check for too many columns,
it emerges that there are some intermediate bits of code that don't
check and can be driven to failure with sufficiently many columns.
Checking this at parse time seems like the most appropriate place to
install a defense, since we already check SELECT list length there.

While at it, make the SELECT-list-length error use the same errcode
(TOO_MANY_COLUMNS) as heap_form_tuple does, rather than the generic
PROGRAM_LIMIT_EXCEEDED.

Per bug #17561 from Egor Chindyaskin.  The given test case crashes
in all supported branches (and probably a lot further back),
so patch all.

Discussion: https://postgr.es/m/17561-80350151b9ad2ad4@postgresql.org
2022-07-29 13:30:50 -04:00
Alvaro Herrera 9a7e26b9c2
Fix replay of create database records on standby
Crash recovery on standby may encounter missing directories
when replaying database-creation WAL records.  Prior to this
patch, the standby would fail to recover in such a case;
however, the directories could be legitimately missing.
Consider the following sequence of commands:

    CREATE DATABASE
    DROP DATABASE
    DROP TABLESPACE

If, after replaying the last WAL record and removing the
tablespace directory, the standby crashes and has to replay the
create database record again, crash recovery must be able to continue.

A fix for this problem was already attempted in 49d9cfc68b, but it
was reverted because of design issues.  This new version is based
on Robert Haas' proposal: any missing tablespaces are created
during recovery before reaching consistency.  Tablespaces
are created as real directories, and should be deleted
by later replay.  CheckRecoveryConsistency ensures
they have disappeared.

The problems detected by this new code are reported as PANIC,
except when allow_in_place_tablespaces is set to ON, in which
case they are WARNING.  Apart from making tests possible, this
gives users an escape hatch in case things don't go as planned.

Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Author: Asim R Praveen <apraveen@pivotal.io>
Author: Paul Guo <paulguo@gmail.com>
Reviewed-by: Anastasia Lubennikova <lubennikovaav@gmail.com> (older versions)
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com> (older versions)
Reviewed-by: Michaël Paquier <michael@paquier.xyz>
Diagnosed-by: Paul Guo <paulguo@gmail.com>
Discussion: https://postgr.es/m/CAEET0ZGx9AvioViLf7nbR_8tH9-=27DN5xWJ2P9-ROH16e4JUA@mail.gmail.com
2022-07-28 08:26:05 +02:00
Alvaro Herrera 16e7a8fd8e
Allow "in place" tablespaces.
This is a backpatch to branches 10-14 of the following commits:

7170f2159f Allow "in place" tablespaces.
c6f2f01611 Fix pg_basebackup with in-place tablespaces.
f6f0db4d62 Fix pg_tablespace_location() with in-place tablespaces
7a7cd84893 doc: Remove mention to in-place tablespaces for pg_tablespace_location()
5344723755 Remove unnecessary Windows-specific basebackup code.

In-place tablespaces were introduced as a testing helper mechanism, but
they are going to be used for a bugfix in WAL replay to be backpatched
to all stable branches.

I (Álvaro) had to adjust some code to account for lack of
get_dirent_type() in branches prior to 14.

Author: Thomas Munro <thomas.munro@gmail.com>
Author: Michaël Paquier <michael@paquier.xyz>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20220722081858.omhn2in5zt3g4nek@alvherre.pgsql
2022-07-27 07:55:13 +02:00
Tom Lane 6c193c2ace Force immediate commit after CREATE DATABASE etc in extended protocol.
We have a few commands that "can't run in a transaction block",
meaning that if they complete their processing but then we fail
to COMMIT, we'll be left with inconsistent on-disk state.
However, the existing defenses for this are only watertight for
simple query protocol.  In extended protocol, we didn't commit
until receiving a Sync message.  Since the client is allowed to
issue another command instead of Sync, we're in trouble if that
command fails or is an explicit ROLLBACK.  In any case, sitting
in an inconsistent state while waiting for a client message
that might not come seems pretty risky.

This case wasn't reachable via libpq before we introduced pipeline
mode, but it's always been an intended aspect of extended query
protocol, and likely there are other clients that could reach it
before.

To fix, set a flag in PreventInTransactionBlock that tells
exec_execute_message to force an immediate commit.  This seems
to be the approach that does least damage to existing working
cases while still preventing the undesirable outcomes.

While here, add some documentation to protocol.sgml that explicitly
says how to use pipelining.  That's latent in the existing docs if
you know what to look for, but it's better to spell it out; and it
provides a place to document this new behavior.

Per bug #17434 from Yugo Nagata.  It's been wrong for ages,
so back-patch to all supported branches.

Discussion: https://postgr.es/m/17434-d9f7a064ce2a88a3@postgresql.org
2022-07-26 13:07:03 -04:00
Tom Lane 5b5d435139 Fix ruleutils issues with dropped cols in functions-returning-composite.
Due to lack of concern for the case in the dependency code, it's
possible to drop a column of a composite type even though stored
queries have references to the dropped column via functions-in-FROM
that return the composite type.  There are "soft" references,
namely FROM-clause aliases for such columns, and "hard" references,
that is actual Vars referring to them.  The right fix for hard
references is to add dependencies preventing the drop; something
we've known for many years and not done (and this commit still doesn't
address it).  A "soft" reference shouldn't prevent a drop though.
We've been around on this before (cf. 9b35ddce9, 2c4debbd0), but
nobody had noticed that the current behavior can result in dump/reload
failures, because ruleutils.c can print more column aliases than the
underlying composite type now has.  So we need to rejigger the
column-alias-handling code to treat such columns as dropped and not
print aliases for them.

Rather than writing new code for this, I used expandRTE() which already
knows how to figure out which function result columns are dropped.
I'd initially thought maybe we could use expandRTE() in all cases, but
that fails for EXPLAIN's purposes, because the planner strips a lot of
RTE infrastructure that expandRTE() needs.  So this patch just uses it
for unplanned function RTEs and otherwise does things the old way.

If there is a hard reference (Var), then removing the column alias
causes us to fail to print the Var, since there's no longer a name
to print.  Failing seems less desirable than printing a made-up
name, so I made it print "?dropped?column?" instead.

Per report from Timo Stolz.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/5c91267e-3b6d-5795-189c-d15a55d61dbb@nullachtvierzehn.de
2022-07-21 13:56:02 -04:00
Fujii Masao 162ade612f Fix assertion failure and segmentation fault in backup code.
When a non-exclusive backup is canceled, do_pg_abort_backup() is called
and resets some variables set by pg_backup_start (pg_start_backup in v14
or before). But previously it forgot to reset the session state indicating
whether a non-exclusive backup is in progress or not in this session.

This issue could cause an assertion failure when the session running
BASE_BACKUP is terminated after it executed pg_backup_start and
pg_backup_stop (pg_stop_backup in v14 or before). Also it could cause
a segmentation fault when pg_backup_stop is called after BASE_BACKUP
in the same session is canceled.

This commit fixes the issue by making do_pg_abort_backup reset
that session state.

Back-patch to all supported branches.

Author: Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Masahiko Sawada, Michael Paquier, Robert Haas
Discussion: https://postgr.es/m/3374718f-9fbf-a950-6d66-d973e027f44c@oss.nttdata.com
2022-07-20 09:53:53 +09:00
Fujii Masao 5630f39b31 Prevent BASE_BACKUP in the middle of another backup in the same session.
Multiple non-exclusive backups are able to be run conrrently in different
sessions. But, in the same session, only one non-exclusive backup can be
run at the same moment. If pg_backup_start (pg_start_backup in v14 or before)
is called in the middle of another non-exclusive backup in the same session,
an error is thrown.

However, previously, in logical replication walsender mode, even if that
walsender session had already called pg_backup_start and started
a non-exclusive backup, it could execute BASE_BACKUP command and
start another non-exclusive backup. Which caused subsequent pg_backup_stop
to throw an error because BASE_BACKUP unexpectedly reset the session state
marked by pg_backup_start.

This commit prevents BASE_BACKUP command in the middle of another
non-exclusive backup in the same session.

Back-patch to all supported branches.

Author: Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Masahiko Sawada, Michael Paquier, Robert Haas
Discussion: https://postgr.es/m/3374718f-9fbf-a950-6d66-d973e027f44c@oss.nttdata.com
2022-07-20 09:52:23 +09:00
Peter Eisentraut b2c8d56618 Re-add SPICleanup for ABI compatibility in stable branch
This fixes an ABI break introduced by
cfc86f9873.

Author: Markus Wanner <markus.wanner@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/defd749a-8410-841d-1126-21398686d63d@enterprisedb.com
2022-07-18 19:20:07 +02:00
Tom Lane 36ccca3dba Fix omissions in support for the "regcollation" type.
The patch that added regcollation doesn't seem to have been too
thorough about supporting it everywhere that other reg* types
are supported.  Fix that.  (The find_expr_references omission
is moderately serious, since it could result in missing expression
dependencies.  The others are less exciting.)

Noted while fixing bug #17483.  Back-patch to v13 where
regcollation was added.

Discussion: https://postgr.es/m/1423433.1652722406@sss.pgh.pa.us
2022-07-17 17:43:28 -04:00
Thomas Munro c75b6b454e Make dsm_impl_posix_resize more future-proof.
Commit 4518c798 blocks signals for a short region of code, but it
assumed that whatever called it had the signal mask set to UnBlockSig on
entry.  That may be true today (or may even not be, in extensions in the
wild), but it would be better not to make that assumption.  We should
save-and-restore the caller's signal mask.

The PG_SETMASK() portability macro couldn't be used for that, which is
why it wasn't done before.  But... considering that commit a65e0864
established back in 9.6 that supported POSIX systems have sigprocmask(),
and that this is POSIX-only code, there is no reason not to use standard
sigprocmask() directly to achieve that.

Back-patch to all supported releases, like 4518c798 and 80845b7c.

Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKGKx6Biq7_UuV0kn9DW%2B8QWcpJC1qwhizdtD9tN-fn0H0g%40mail.gmail.com
2022-07-16 12:23:24 +12:00
Thomas Munro 17aa39da50 Don't clobber postmaster sigmask in dsm_impl_resize.
Commit 4518c798 intended to block signals in regular backends that
allocate DSM segments, but dsm_impl_resize() is also reached by
dsm_postmaster_startup().  It's not OK to clobber the postmaster's
signal mask, so only manipulate the signal mask when under the
postmaster.

Back-patch to all releases, like 4518c798.

Discussion: https://postgr.es/m/CA%2BhUKGKNpK%3D2OMeea_AZwpLg7Bm4%3DgYWk7eDjZ5F6YbozfOf8w%40mail.gmail.com
2022-07-15 02:04:53 +12:00
Thomas Munro e73fe6e828 Block signals while allocating DSM memory.
On Linux, we call posix_fallocate() on shm_open()'d memory to avoid
later potential SIGBUS (see commit 899bd785).

Based on field reports of systems stuck in an EINTR retry loop there,
there, we made it possible to break out of that loop via slightly odd
coding where the CHECK_FOR_INTERRUPTS() call was somewhat removed from
the loop (see commit 422952ee).

On further reflection, that was not a great choice for at least two
reasons:

1.  If interrupts were held, the CHECK_FOR_INTERRUPTS() would do nothing
and the EINTR error would be surfaced to the user.

2.  If EINTR was reported but neither QueryCancelPending nor
ProcDiePending was set, then we'd dutifully retry, but with a bit more
understanding of how posix_fallocate() works, it's now clear that you
can get into a loop that never terminates.  posix_fallocate() is not a
function that can do some of the job and tell you about progress if it's
interrupted, it has to undo what it's done so far and report EINTR, and
if signals keep arriving faster than it can complete (cf recovery
conflict signals), you're stuck.

Therefore, for now, we'll simply block most signals to guarantee
progress.  SIGQUIT is not blocked (see InitPostmasterChild()), because
its expected handler doesn't return, and unblockable signals like
SIGCONT are not expected to arrive at a high rate.  For good measure,
we'll include the ftruncate() call in the blocked region, and add a
retry loop.

Back-patch to all supported releases.

Reported-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Nicola Contu <nicola.contu@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20220701154105.jjfutmngoedgiad3%40alvherre.pgsql
2022-07-14 14:32:48 +12:00
Thomas Munro 7cdd0c2d7c Fix lock assertions in dshash.c.
dshash.c previously maintained flags to be able to assert that you
didn't hold any partition lock.  These flags could get out of sync with
reality in error scenarios.

Get rid of all that, and make assertions about the locks themselves
instead.  Since LWLockHeldByMe() loops internally, we don't want to put
that inside another loop over all partition locks.  Introduce a new
debugging-only interface LWLockAnyHeldByMe() to avoid that.

This problem was noted by Tom and Andres while reviewing changes to
support the new shared memory stats system, and later showed up in
reality while working on commit 389869af.

Back-patch to 11, where dshash.c arrived.

Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20220311012712.botrpsikaufzteyt@alap3.anarazel.de
Discussion: https://postgr.es/m/CA%2BhUKGJ31Wce6HJ7xnVTKWjFUWQZPBngxfJVx4q0E98pDr3kAw%40mail.gmail.com
2022-07-11 15:48:54 +12:00
Dean Rasheed f890223bc3 Fix alias matching in transformLockingClause().
When locking a specific named relation for a FOR [KEY] UPDATE/SHARE
clause, transformLockingClause() finds the relation to lock by
scanning the rangetable for an RTE with a matching eref->aliasname.
However, it failed to account for the visibility rules of a join RTE.

If a join RTE doesn't have a user-supplied alias, it will have a
generated eref->aliasname of "unnamed_join" that is not visible as a
relation name in the parse namespace. Such an RTE needs to be skipped,
otherwise it might be found in preference to a regular base relation
with a user-supplied alias of "unnamed_join", preventing it from being
locked.

In addition, if a join RTE doesn't have a user-supplied alias, but
does have a join_using_alias, then the RTE needs to be matched using
that alias rather than the generated eref->aliasname, otherwise a
misleading "relation not found" error will be reported rather than a
"join cannot be locked" error.

Backpatch all the way, except for the second part which only goes back
to 14, where JOIN USING aliases were added.

Dean Rasheed, reviewed by Tom Lane.

Discussion: https://postgr.es/m/CAEZATCUY_KOBnqxbTSPf=7fz9HWPnZ5Xgb9SwYzZ8rFXe7nb=w@mail.gmail.com
2022-07-07 13:08:00 +01:00
Andrew Dunstan 03cefe8148 Remove %error-verbose directive from jsonpath parser
None of the other bison parsers contains this directive, and it gives
rise to some unfortunate and impenetrable messages, so just remove it.

Backpatch to release 12, where it was introduced.

Per gripe from Erik Rijkers

Discussion: https://postgr.es/m/ba069ce2-a98f-dc70-dc17-2ccf2a9bf7c7@xs4all.nl
2022-07-03 17:16:58 -04:00
Thomas Munro b436047dc6 Harden dsm_impl.c against unexpected EEXIST.
Previously, we trusted the OS not to report EEXIST unless we'd passed in
IPC_CREAT | IPC_EXCL or O_CREAT | O_EXCL, as appropriate.  Solaris's
shm_open() can in fact do that, causing us to crash because we didn't
ereport and then we blithely assumed the mapping was successful.

Let's treat EEXIST just like any other error, unless we're actually
trying to create a new segment.  This applies to shm_open(), where this
behavior has been seen, and also to the equivalent operations for our
sysv and mmap modes just on principle.

Based on the underlying reason for the error, namely contention on a
lock file managed by Solaris librt for each distinct name, this problem
is only likely to happen on 15 and later, because the new shared memory
stats system produces shm_open() calls for the same path from
potentially large numbers of backends concurrently during
authentication.  Earlier releases only shared memory segments between a
small number of parallel workers under one Gather node.  You could
probably hit it if you tried hard enough though, and we should have been
more defensive in the first place.  Therefore, back-patch to all
supported releases.

Per build farm animal margay.  This isn't the end of the story, though,
it just changes random crashes into random "File exists" errors; more
work needed for a green build farm.

Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGKqKrCV5xKWfh9rnm%3Do%3DDwZLTLtnsj_XpUi9g5%3DV%2B9oyg%40mail.gmail.com
2022-07-01 14:03:48 +12:00
Heikki Linnakangas 7ba325fd7f Fix visibility check when XID is committed in CLOG but not in procarray.
TransactionIdIsInProgress had a fast path to return 'false' if the
single-item CLOG cache said that the transaction was known to be
committed. However, that was wrong, because a transaction is first
marked as committed in the CLOG but doesn't become visible to others
until it has removed its XID from the proc array. That could lead to an
error:

    ERROR:  t_xmin is uncommitted in tuple to be updated

or for an UPDATE to go ahead without blocking, before the previous
UPDATE on the same row was made visible.

The window is usually very short, but synchronous replication makes it
much wider, because the wait for synchronous replica happens in that
window.

Another thing that makes it hard to hit is that it's hard to get such
a commit-in-progress transaction into the single item CLOG cache.
Normally, if you call TransactionIdIsInProgress on such a transaction,
it determines that the XID is in progress without checking the CLOG
and without populating the cache. One way to prime the cache is to
explicitly call pg_xact_status() on the XID. Another way is to use a
lot of subtransactions, so that the subxid cache in the proc array is
overflown, making TransactionIdIsInProgress rely on pg_subtrans and
CLOG checks.

This has been broken ever since it was introduced in 2008, but the race
condition is very hard to hit, especially without synchronous
replication. There were a couple of reports of the error starting from
summer 2021, but no one was able to find the root cause then.

TransactionIdIsKnownCompleted() is now unused. In 'master', remove it,
but I left it in place in backbranches in case it's used by extensions.

Also change pg_xact_status() to check TransactionIdIsInProgress().
Previously, it only checked the CLOG, and returned "committed" before
the transaction was actually made visible to other queries. Note that
this also means that you cannot use pg_xact_status() to reproduce the
bug anymore, even if the code wasn't fixed.

Report and analysis by Konstantin Knizhnik. Patch by Simon Riggs, with
the pg_xact_status() change added by me.

Author: Simon Riggs
Reviewed-by: Andres Freund
Discussion: https://www.postgresql.org/message-id/flat/4da7913d-398c-e2ad-d777-f752cf7f0bbb%40garret.ru
2022-06-27 08:24:35 +03:00
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
Amit Kapila 3a6ef0cdf3 Fix memory leak due to LogicalRepRelMapEntry.attrmap.
When rebuilding the relation mapping on subscribers, we were not releasing
the attribute mapping's memory which was no longer required.

The attribute mapping used in logical tuple conversion was refactored in
PG13 (by commit e1551f96e6) but we forgot to update the related code that
frees the attribute map.

Author: Hou Zhijie
Reviewed-by: Amit Langote, Amit Kapila, Shi yu
Backpatch-through: 10, where it was introduced
Discussion: https://postgr.es/m/OSZPR01MB6310F46CD425A967E4AEF736FDA49@OSZPR01MB6310.jpnprd01.prod.outlook.com
2022-06-23 09:02:16 +05:30
Tom Lane cfc86f9873 Fix SPI's handling of errors during transaction commit.
SPI_commit previously left it up to the caller to recover from any error
occurring during commit.  Since that's complicated and requires use of
low-level xact.c facilities, it's not too surprising that no caller got
it right.  Let's move the responsibility for cleanup into spi.c.  Doing
that requires redefining SPI_commit as starting a new transaction, so
that it becomes equivalent to SPI_commit_and_chain except that you get
default transaction characteristics instead of preserving the prior
transaction's characteristics.  We can make this pretty transparent
API-wise by redefining SPI_start_transaction() as a no-op.  Callers
that expect to do something in between might be surprised, but
available evidence is that no callers do so.

Having made that API redefinition, we can fix this mess by having
SPI_commit[_and_chain] trap errors and start a new, clean transaction
before re-throwing the error.  Likewise for SPI_rollback[_and_chain].
Some cleanup is also needed in AtEOXact_SPI, which was nowhere near
smart enough to deal with SPI contexts nested inside a committing
context.

While plperl and pltcl need no changes beyond removing their now-useless
SPI_start_transaction() calls, plpython needs some more work because it
hadn't gotten the memo about catching commit/rollback errors in the
first place.  Such an error resulted in longjmp'ing out of the Python
interpreter, which leaks Python stack entries at present and is reported
to crash Python 3.11 altogether.  Add the missing logic to catch such
errors and convert them into Python exceptions.

This is a back-patch of commit 2e517818f.  That's now aged long enough
to reduce the concerns about whether it will break something, and we
do need to ensure that supported branches will work with Python 3.11.

Peter Eisentraut and Tom Lane

Discussion: https://postgr.es/m/3375ffd8-d71c-2565-e348-a597d6e739e3@enterprisedb.com
Discussion: https://postgr.es/m/17416-ed8fe5d7213d6c25@postgresql.org
2022-06-22 12:12:00 -04:00
Amit Kapila 419c727151 Fix stale values in partition map entries on subscribers.
We build the partition map entries on subscribers while applying the
changes for update/delete on partitions. The component relation in each
entry is closed after its use so we need to update it on successive use of
cache entries.

This problem was there since the original commit f1ac27bfda that
introduced this code but we didn't notice it till the recent commit
26b3455afa started to use the component relation of partition map cache
entry.

Reported-by: Tom Lane, as per buildfarm
Author: Amit Langote, Hou Zhijie
Reviewed-by: Amit Kapila, Shi Yu
Backpatch-through: 13, where it was introduced
Discussion: https://postgr.es/m/OSZPR01MB6310F46CD425A967E4AEF736FDA49@OSZPR01MB6310.jpnprd01.prod.outlook.com
2022-06-21 15:12:52 +05:30
Amit Kapila 5f113d60e9 Fix partition table's REPLICA IDENTITY checking on the subscriber.
In logical replication, we will check if the target table on the
subscriber is updatable by comparing the replica identity of the table on
the publisher with the table on the subscriber. When the target table is a
partitioned table, we only check its replica identity but not for the
partition tables. This leads to assertion failure while applying changes
for update/delete as we expect those to succeed only when the
corresponding partition table has a primary key or has a replica
identity defined.

Fix it by checking the replica identity of the partition table while
applying changes.

Reported-by: Shi Yu
Author: Shi Yu, Hou Zhijie
Reviewed-by: Amit Langote, Amit Kapila
Backpatch-through: 13, where it was introduced
Discussion: https://postgr.es/m/OSZPR01MB6310F46CD425A967E4AEF736FDA49@OSZPR01MB6310.jpnprd01.prod.outlook.com
2022-06-21 08:05:31 +05:30
Amit Kapila 1f9a7738eb Fix data inconsistency between publisher and subscriber.
We were not updating the partition map cache in the subscriber even when
the corresponding remote rel is changed. Due to this data was getting
incorrectly replicated for partition tables after the publisher has
changed the table schema.

Fix it by resetting the required entries in the partition map cache after
receiving a new relation mapping from the publisher.

Reported-by: Shi Yu
Author: Shi Yu, Hou Zhijie
Reviewed-by: Amit Langote, Amit Kapila
Backpatch-through: 13, where it was introduced
Discussion: https://postgr.es/m/OSZPR01MB6310F46CD425A967E4AEF736FDA49@OSZPR01MB6310.jpnprd01.prod.outlook.com
2022-06-16 08:24:22 +05:30
Amit Kapila 16f5a8da76 Fix cache look-up failures while applying changes in logical replication.
While building a new attrmap which maps partition attribute numbers to
remoterel's, we incorrectly update the map for dropped column attributes.
Later, it caused cache look-up failure when we tried to use the map to
fetch the information about attributes.

This also fixes the partition map cache invalidation which was using the
wrong type cast to fetch the entry. We were using stale partition map
entry after invalidation which leads to the assertion or cache look-up
failure.

Reported-by: Shi Yu
Author: Hou Zhijie, Shi Yu
Reviewed-by: Amit Langote, Amit Kapila
Backpatch-through: 13, where it was introduced
Discussion: https://postgr.es/m/OSZPR01MB6310F46CD425A967E4AEF736FDA49@OSZPR01MB6310.jpnprd01.prod.outlook.com
2022-06-15 10:16:35 +05:30
Tom Lane 254cd7f31f Un-break whole-row Vars referencing domain-over-composite types.
In commit ec62cb0aa, I foolishly replaced ExecEvalWholeRowVar's
lookup_rowtype_tupdesc_domain call with just lookup_rowtype_tupdesc,
because I didn't see how a domain could be involved there, and
there were no regression test cases to jog my memory.  But the
existing code was correct, so revert that change and add a test
case showing why it's necessary.  (Note: per comment in struct
DatumTupleFields, it is correct to produce an output tuple that's
labeled with the base composite type, not the domain; hence just
blindly looking through the domain is correct here.)

Per bug #17515 from Dan Kubb.  Back-patch to v11 where domains over
composites became a thing.

Discussion: https://postgr.es/m/17515-a24737438363aca0@postgresql.org
2022-06-10 10:35:57 -04:00
Tom Lane a36196972b Fix off-by-one loop termination condition in pg_stat_get_subscription().
pg_stat_get_subscription scanned one more LogicalRepWorker array entry
than is really allocated.  In the worst case this could lead to SIGSEGV,
if the LogicalRepCtx data structure is near the end of shared memory.
That seems quite unlikely though (thanks to the ordering of calls in
CreateSharedMemoryAndSemaphores) and we've heard no field reports of it.
A more likely misbehavior is one row of garbage data in the function's
result, but even that is not real likely because of the check that the
pid field matches some live backend.

Report and fix by Kuntal Ghosh.  This bug is old, so back-patch
to all supported branches.

Discussion: https://postgr.es/m/CAGz5QCJykEDzW6jQK6Yz7Qh_PMtD=95de_7QoocbVR2Qy8hWZA@mail.gmail.com
2022-06-07 15:34:30 -04:00
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
Tom Lane c73748b68a Ensure ParseTzFile() closes the input file after failing.
We hadn't noticed this because (a) few people feed invalid
timezone abbreviation files to the server, and (b) in typical
scenarios guc.c would throw ereport(ERROR) and then transaction
abort handling would silently clean up the leaked file reference.
However, it was possible to observe file leakage warnings if one
breaks an already-active abbreviation file, because guc.c does
not throw ERROR when loading supposedly-validated settings during
session start or SIGHUP processing.

Report and fix by Kyotaro Horiguchi (cosmetic adjustments by me)

Discussion: https://postgr.es/m/20220530.173740.748502979257582392.horikyota.ntt@gmail.com
2022-05-31 14:47:44 -04:00
Michael Paquier 1e6802990c Handle NULL for short descriptions of custom GUC variables
If a short description is specified as NULL in one of the various
DefineCustomXXXVariable() functions available to external modules to
define a custom parameter, SHOW ALL would crash.  This change teaches
SHOW ALL to properly handle NULL short descriptions, as well as any code
paths that manipulate it, to gain in flexibility.  Note that
help_config.c was already able to do that, when describing a set of GUCs
for postgres --describe-config.

Author: Steve Chavez
Reviewed by: Nathan Bossart, Andres Freund, Michael Paquier, Tom Lane
Discussion: https://postgr.es/m/CAGRrpzY6hO-Kmykna_XvsTv8P2DshGiU6G3j8yGao4mk0CqjHA%40mail.gmail.com
Backpatch-through: 10
2022-05-28 12:12:51 +09:00
Tom Lane 9e3dbc6fd9 Remove misguided SSL key file ownership check in libpq.
Commits a59c79564 et al. tried to sync libpq's SSL key file
permissions checks with what we've used for years in the backend.
We did not intend to create any new failure cases, but it turns out
we did: restricting the key file's ownership breaks cases where the
client is allowed to read a key file despite not having the identical
UID.  In particular a client running as root used to be able to read
someone else's key file; and having seen that I suspect that there are
other, less-dubious use cases that this restriction breaks on some
platforms.

We don't really need an ownership check, since if we can read the key
file despite its having restricted permissions, it must have the right
ownership --- under normal conditions anyway, and the point of this
patch is that any additional corner cases where that works should be
deemed allowable, as they have been historically.  Hence, just drop
the ownership check, and rearrange the permissions check to get rid
of its faulty assumption that geteuid() can't be zero.  (Note that the
comparable backend-side code doesn't have to cater for geteuid() == 0,
since the server rejects that very early on.)

This does have the end result that the permissions safety check used
for a root user's private key file is weaker than that used for
anyone else's.  While odd, root really ought to know what she's doing
with file permissions, so I think this is acceptable.

Per report from Yogendra Suralkar.  Like the previous patch,
back-patch to all supported branches.

Discussion: https://postgr.es/m/MW3PR15MB3931DF96896DC36D21AFD47CA3D39@MW3PR15MB3931.namprd15.prod.outlook.com
2022-05-26 14:14:05 -04:00
Tom Lane fefd546317 Show 'AS "?column?"' explicitly when it's important.
ruleutils.c was coded to suppress the AS label for a SELECT output
expression if the column name is "?column?", which is the parser's
fallback if it can't think of something better.  This is fine, and
avoids ugly clutter, so long as (1) nothing further up in the parse
tree relies on that column name or (2) the same fallback would be
assigned when the rule or view definition is reloaded.  Unfortunately
(2) is far from certain, both because ruleutils.c might print the
expression in a different form from how it was originally written
and because FigureColname's rules might change in future releases.
So we shouldn't rely on that.

Detecting exactly whether there is any outer-level use of a SELECT
column name would be rather expensive.  This patch takes the simpler
approach of just passing down a flag indicating whether there *could*
be any outer use; for example, the output column names of a SubLink
are not referenceable, and we also do not care about the names exposed
by the right-hand side of a setop.  This is sufficient to suppress
unwanted clutter in all but one case in the regression tests.  That
seems like reasonable evidence that it won't be too much in users'
faces, while still fixing the cases we need to fix.

Per bug #17486 from Nicolas Lutic.  This issue is ancient, so
back-patch to all supported branches.

Discussion: https://postgr.es/m/17486-1ad6fd786728b8af@postgresql.org
2022-05-21 14:45:58 -04:00
Alvaro Herrera 3753a169e1
Fix DDL deparse of CREATE OPERATOR CLASS
When an implicit operator family is created, it wasn't getting reported.
Make it do so.

This has always been missing.  Backpatch to 10.

Author: Masahiko Sawada <sawada.mshk@gmail.com>
Reported-by: Leslie LEMAIRE <leslie.lemaire@developpement-durable.gouv.fr>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Michael Paquiër <michael@paquier.xyz>
Discussion: https://postgr.es/m/f74d69e151b22171e8829551b1159e77@developpement-durable.gouv.fr
2022-05-20 18:52:55 +02:00
Alvaro Herrera 5fd0cccc11
Repurpose PROC_COPYABLE_FLAGS as PROC_XMIN_FLAGS
This is a slight, convenient semantics change from what commit
0f0cfb4940 ("Fix parallel operations that prevent oldest xmin from
advancing") introduced that lets us simplify the coding in the one place
where it is used.

Backpatch to 13.  This is related to commit 6fea65508a ("Tighten
ComputeXidHorizons' handling of walsenders") rewriting the code site
where this is used, which has not yet been backpatched, but it may well
be in the future.

Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/202204191637.eldwa2exvguw@alvherre.pgsql
2022-05-19 16:20:32 +02:00
Alvaro Herrera 80656f00f8
Check column list length in XMLTABLE/JSON_TABLE alias
We weren't checking the length of the column list in the alias clause of
an XMLTABLE or JSON_TABLE function (a "tablefunc" RTE), and it was
possible to make the server crash by passing an overly long one.  Fix it
by throwing an error in that case, like the other places that deal with
alias lists.

In passing, modify the equivalent test used for join RTEs to look like
the other ones, which was different for no apparent reason.

This bug came in when XMLTABLE was born in version 10; backpatch to all
stable versions.

Reported-by: Wang Ke <krking@zju.edu.cn>
Discussion: https://postgr.es/m/17480-1c9d73565bb28e90@postgresql.org
2022-05-18 20:28:31 +02:00
Michael Paquier 2e9559b302 Fix control file update done in restartpoints still running after promotion
If a cluster is promoted (aka the control file shows a state different
than DB_IN_ARCHIVE_RECOVERY) while CreateRestartPoint() is still
processing, this function could miss an update of the control file for
"checkPoint" and "checkPointCopy" but still do the recycling and/or
removal of the past WAL segments, assuming that the to-be-updated LSN
values should be used as reference points for the cleanup.  This causes
a follow-up restart attempting crash recovery to fail with a PANIC on a
missing checkpoint record if the end-of-recovery checkpoint triggered by
the promotion did not complete while the cluster abruptly stopped or
crashed before the completion of this checkpoint.  The PANIC would be
caused by the redo LSN referred in the control file as located in a
segment already gone, recycled by the previous restartpoint with
"checkPoint" out-of-sync in the control file.

This commit fixes the update of the control file during restartpoints so
as "checkPoint" and "checkPointCopy" are updated even if the cluster has
been promoted while a restartpoint is running, to be on par with the set
of WAL segments actually recycled in the end of CreateRestartPoint().

7863ee4 has fixed this problem already on master, but the release timing
of the latest point versions did not let me enough time to study and fix
that on all the stable branches.

Reported-by: Fujii Masao, Rui Zhao
Author: Kyotaro Horiguchi
Reviewed-by: Nathan Bossart, Michael Paquier
Discussion: https://postgr.es/m/20220316.102444.2193181487576617583.horikyota.ntt@gmail.com
Backpatch-through: 10
2022-05-16 11:26:26 +09:00
Tom Lane b7579b25c8 Make pull_var_clause() handle GroupingFuncs exactly like Aggrefs.
This follows in the footsteps of commit 2591ee8ec by removing one more
ill-advised shortcut from planning of GroupingFuncs.  It's true that
we don't intend to execute the argument expression(s) at runtime, but
we still have to process any Vars appearing within them, or we risk
failure at setrefs.c time (or more fundamentally, in EXPLAIN trying
to print such an expression).  Vars in upper plan nodes have to have
referents in the next plan level, whether we ever execute 'em or not.

Per bug #17479 from Michael J. Sullivan.  Back-patch to all supported
branches.

Richard Guo

Discussion: https://postgr.es/m/17479-6260deceaf0ad304@postgresql.org
2022-05-12 11:31:46 -04:00
Amit Kapila 55558df237 Fix the logical replication timeout during large transactions.
The problem is that we don't send keep-alive messages for a long time
while processing large transactions during logical replication where we
don't send any data of such transactions. This can happen when the table
modified in the transaction is not published or because all the changes
got filtered. We do try to send the keep_alive if necessary at the end of
the transaction (via WalSndWriteData()) but by that time the
subscriber-side can timeout and exit.

To fix this we try to send the keepalive message if required after
processing certain threshold of changes.

Reported-by: Fabrice Chapuis
Author: Wang wei and Amit Kapila
Reviewed By: Masahiko Sawada, Euler Taveira, Hou Zhijie, Hayato Kuroda
Backpatch-through: 10
Discussion: https://postgr.es/m/CAA5-nLARN7-3SLU_QUxfy510pmrYK6JJb=bk3hcgemAM_pAv+w@mail.gmail.com
2022-05-11 10:41:24 +05:30
Tom Lane 91a3a74c65 Fix core dump in transformValuesClause when there are no columns.
The parser code that transformed VALUES from row-oriented to
column-oriented lists failed if there were zero columns.
You can't write that straightforwardly (though probably you
should be able to), but the case can be reached by expanding
a "tab.*" reference to a zero-column table.

Per bug #17477 from Wang Ke.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/17477-0af3c6ac6b0a6ae0@postgresql.org
2022-05-09 14:15:37 -04:00
Tom Lane 7f0754bc4c Revert "Disallow infinite endpoints in generate_series() for timestamps."
This reverts commit eafdf9de06
and its back-branch counterparts.  Corey Huinker pointed out that
we'd discussed this exact change back in 2016 and rejected it,
on the grounds that there's at least one usage pattern with LIMIT
where an infinite endpoint can usefully be used.  Perhaps that
argument needs to be re-litigated, but there's no time left before
our back-branch releases.  To keep our options open, restore the
status quo ante; if we do end up deciding to change things, waiting
one more quarter won't hurt anything.

Rather than just doing a straight revert, I added a new test case
demonstrating the usage with LIMIT.  That'll at least remind us of
the issue if we forget again.

Discussion: https://postgr.es/m/3603504.1652068977@sss.pgh.pa.us
Discussion: https://postgr.es/m/CADkLM=dzw0Pvdqp5yWKxMd+VmNkAMhG=4ku7GnCZxebWnzmz3Q@mail.gmail.com
2022-05-09 11:40:41 -04:00
Noah Misch 88743d581e In REFRESH MATERIALIZED VIEW, set user ID before running user code.
It intended to, but did not, achieve this.  Adopt the new standard of
setting user ID just after locking the relation.  Back-patch to v10 (all
supported versions).

Reviewed by Simon Riggs.  Reported by Alvaro Herrera.

Security: CVE-2022-1552
2022-05-09 08:35:12 -07:00
Noah Misch 35edcc0cee Make relation-enumerating operations be security-restricted operations.
When a feature enumerates relations and runs functions associated with
all found relations, the feature's user shall not need to trust every
user having permission to create objects.  BRIN-specific functionality
in autovacuum neglected to account for this, as did pg_amcheck and
CLUSTER.  An attacker having permission to create non-temp objects in at
least one schema could execute arbitrary SQL functions under the
identity of the bootstrap superuser.  CREATE INDEX (not a
relation-enumerating operation) and REINDEX protected themselves too
late.  This change extends to the non-enumerating amcheck interface.
Back-patch to v10 (all supported versions).

Sergey Shinderuk, reviewed (in earlier versions) by Alexander Lakhin.
Reported by Alexander Lakhin.

Security: CVE-2022-1552
2022-05-09 08:35:12 -07:00
Peter Eisentraut 916463773c Translation updates
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: 7c8dcb6669ccc6ae33090d02ed92f0bad6ada742
2022-05-09 12:27:22 +02:00
Andres Freund 57c5ad168b Fix possibility of self-deadlock in ResolveRecoveryConflictWithBufferPin().
The tests added in 9f8a050f68 failed nearly reliably on FreeBSD in CI, and
occasionally on the buildfarm. That turns out to be caused not by a bug in the
test, but by a longstanding bug in recovery conflict handling.

The standby timeout handler, used by ResolveRecoveryConflictWithBufferPin(),
executed SendRecoveryConflictWithBufferPin() inside a signal handler. A bad
idea, because the deadlock timeout handler (or a spurious latch set) could
have interrupted ProcWaitForSignal(). If unlucky that could cause a
self-deadlock on ProcArrayLock, if the deadlock check is in
SendRecoveryConflictWithBufferPin()->CancelDBBackends().

To fix, set a flag in StandbyTimeoutHandler(), and check the flag in
ResolveRecoveryConflictWithBufferPin().

Subsequently the recovery conflict tests will be backpatched.

Discussion: https://postgr.es/m/20220413002626.udl7lll7f3o7nre7@alap3.anarazel.de
Backpatch: 10-
2022-05-02 18:28:10 -07:00
Etsuro Fujita d85f2bfa09 Fix typo in comment. 2022-05-02 16:45:04 +09:00
Tom Lane e6440d5007 Remove inadequate assertion check in CTE inlining.
inline_cte() expected to find exactly as many references to the
target CTE as its cterefcount indicates.  While that should be
accurate for the tree as emitted by the parser, there are some
optimizations that occur upstream of here that could falsify it,
notably removal of unused subquery output expressions.

Trying to make the accounting 100% accurate seems expensive and
doomed to future breakage.  It's not really worth it, because
all this code is protecting is downstream assumptions that every
referenced CTE has a plan.  Let's convert those assertions to
regular test-and-elog just in case there's some actual problem,
and then drop the failing assertion.

Per report from Tomas Vondra (thanks also to Richard Guo for
analysis).  Back-patch to v12 where the faulty code came in.

Discussion: https://postgr.es/m/29196a1e-ed47-c7ca-9be2-b1c636816183@enterprisedb.com
2022-04-21 17:58:52 -04:00
Peter Geoghegan 1272630a24 Fix CLUSTER tuplesorts on abbreviated expressions.
CLUSTER sort won't use the datum1 SortTuple field when clustering
against an index whose leading key is an expression.  This makes it
unsafe to use the abbreviated keys optimization, which was missed by the
logic that sets up SortSupport state.  Affected tuplesorts output tuples
in a completely bogus order as a result (the wrong SortSupport based
comparator was used for the leading attribute).

This issue is similar to the bug fixed on the master branch by recent
commit cc58eecc5d.  But it's a far older issue, that dates back to the
introduction of the abbreviated keys optimization by commit 4ea51cdfe8.

Backpatch to all supported versions.

Author: Peter Geoghegan <pg@bowt.ie>
Author: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CA+hUKG+bA+bmwD36_oDxAoLrCwZjVtST2fqe=b4=qZcmU7u89A@mail.gmail.com
Backpatch: 10-
2022-04-20 17:17:39 -07:00
Tom Lane 8275ba773d Disallow infinite endpoints in generate_series() for timestamps.
Such cases will lead to infinite loops, so they're of no practical
value.  The numeric variant of generate_series() already threw error
for this, so borrow its message wording.

Per report from Richard Wesley.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/91B44E7B-68D5-448F-95C8-B4B3B0F5DEAF@duckdblabs.com
2022-04-20 18:08:15 -04:00
Tom Lane f583633bc1 Fix breakage in AlterFunction().
An ALTER FUNCTION command that tried to update both the function's
proparallel property and its proconfig list failed to do the former,
because it stored the new proparallel value into a tuple that was
no longer the interesting one.  Carelessness in 7aea8e4f2.

(I did not bother with a regression test, because the only likely
future breakage would be for someone to ignore the comment I added
and add some other field update after the heap_modify_tuple step.
A test using existing function properties could not catch that.)

Per report from Bryn Llewellyn.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/8AC9A37F-99BD-446F-A2F7-B89AD0022774@yugabyte.com
2022-04-19 23:03:59 -04:00
Amit Kapila 82d4a17a17 Fix the check to limit sync workers.
We don't allow to invoke more sync workers once we have reached the sync
worker limit per subscription. But the check to enforce this also doesn't
allow to launch an apply worker if it gets restarted.

This code was introduced by commit de43897122 but we caught the problem
only with the test added by recent commit c91f71b9dc which started failing
occasionally in the buildfarm.

As per buildfarm.
Diagnosed-by: Amit Kapila, Masahiko Sawada, Tomas Vondra
Author: Amit Kapila
Backpatch-through: 10
Discussion: https://postgr.es/m/CAH2L28vddB_NFdRVpuyRBJEBWjz4BSyTB=_ektNRH8NJ1jf95g@mail.gmail.com
	    https://postgr.es/m/f90d2b03-4462-ce95-a524-d91464e797c8@enterprisedb.com
2022-04-19 09:08:05 +05:30
Tom Lane 69cefb3fb8 Avoid invalid array reference in transformAlterTableStmt().
Don't try to look at the attidentity field of system attributes,
because they're not there in the TupleDescAttr array.  Sometimes
this is harmless because we accidentally pick up a zero, but
otherwise we'll report "no owned sequence found" from an attempt
to alter a system attribute.  (It seems possible that a SIGSEGV
could occur, too, though I've not seen it in testing.)

It's not in this function's charter to complain that you can't
alter a system column, so instead just hard-wire an assumption
that system attributes aren't identities.  I didn't bother with
a regression test because the appearance of the bug is very
erratic.

Per bug #17465 from Roman Zharkov.  Back-patch to all supported
branches.  (There's not actually a live bug before v12, because
before that get_attidentity() did the right thing anyway.
But for consistency I changed the test in the older branches too.)

Discussion: https://postgr.es/m/17465-f2a554a6cb5740d3@postgresql.org
2022-04-18 12:16:45 -04:00
Robert Haas d18c913b78 Rethink the delay-checkpoint-end mechanism in the back-branches.
The back-patch of commit bbace5697d had
the unfortunate effect of changing the layout of PGPROC in the
back-branches, which could break extensions. This happened because it
changed the delayChkpt from type bool to type int. So, change it back,
and add a new bool delayChkptEnd field instead. The new field should
fall within what used to be padding space within the struct, and so
hopefully won't cause any extensions to break.

Per report from Markus Wanner and discussion with Tom Lane and others.

Patch originally by me, somewhat revised by Markus Wanner per a
suggestion from Michael Paquier. A very similar patch was developed
by Kyotaro Horiguchi, but I failed to see the email in which that was
posted before writing one of my own.

Discussion: http://postgr.es/m/CA+Tgmoao-kUD9c5nG5sub3F7tbo39+cdr8jKaOVEs_1aBWcJ3Q@mail.gmail.com
Discussion: http://postgr.es/m/20220406.164521.17171257901083417.horikyota.ntt@gmail.com
2022-04-14 11:10:11 -04:00
Tom Lane 44096c31ea Prevent access to no-longer-pinned buffer in heapam_tuple_lock().
heap_fetch() used to have a "keep_buf" parameter that told it to return
ownership of the buffer pin to the caller after finding that the
requested tuple TID exists but is invisible to the specified snapshot.
This was thoughtlessly removed in commit 5db6df0c0, which broke
heapam_tuple_lock() (formerly EvalPlanQualFetch) because that function
needs to do more accesses to the tuple even if it's invisible.  The net
effect is that we would continue to touch the page for a microsecond or
two after releasing pin on the buffer.  Usually no harm would result;
but if a different session decided to defragment the page concurrently,
we could see garbage data and mistakenly conclude that there's no newer
tuple version to chain up to.  (It's hard to say whether this has
happened in the field.  The bug was actually found thanks to a later
change that allowed valgrind to detect accesses to non-pinned buffers.)

The most reasonable way to fix this is to reintroduce keep_buf,
although I made it behave slightly differently: buffer ownership
is passed back only if there is a valid tuple at the requested TID.
In HEAD, we can just add the parameter back to heap_fetch().
To avoid an API break in the back branches, introduce an additional
function heap_fetch_extended() in those branches.

In HEAD there is an additional, less obvious API change: tuple->t_data
will be set to NULL in all cases where buffer ownership is not returned,
in particular when the tuple exists but fails the time qual (and
!keep_buf).  This is to defend against any other callers attempting to
access non-pinned buffers.  We concluded that making that change in back
branches would be more likely to introduce problems than cure any.

In passing, remove a comment about heap_fetch that was obsoleted by
9a8ee1dc6.

Per bug #17462 from Daniil Anisimov.  Back-patch to v12 where the bug
was introduced.

Discussion: https://postgr.es/m/17462-9c98a0f00df9bd36@postgresql.org
2022-04-13 13:35:02 -04:00
Tom Lane 87166d25a4 Suppress "variable 'pagesaving' set but not used" warning.
With asserts disabled, late-model clang notices that this variable
is incremented but never otherwise read.

Discussion: https://postgr.es/m/3171401.1649275153@sss.pgh.pa.us
2022-04-06 17:03:35 -04:00
Etsuro Fujita f042dc6a41 Fix typo in comment. 2022-03-30 19:00:04 +09:00
Alvaro Herrera a54ed2de80
Revert "Fix replay of create database records on standby"
This reverts commit 49d9cfc68b.  The approach taken by this patch has
problems, so we'll come up with a radically different fix.

Discussion: https://postgr.es/m/CA+TgmoYcUPL+WOJL2ZzhH=zmrhj0iOQ=iCFM0SuYqBbqZEamEg@mail.gmail.com
2022-03-29 15:36:21 +02:00
Tom Lane 9016a2a3dc Fix breakage of get_ps_display() in the PS_USE_NONE case.
Commit 8c6d30f21 caused this function to fail to set *displen
in the PS_USE_NONE code path.  If the variable's previous value
had been negative, that'd lead to a memory clobber at some call
sites.  We'd managed not to notice due to very thin test coverage
of such configurations, but this appears to explain buildfarm member
lorikeet's recent struggles.

Credit to Andrew Dunstan for spotting the problem.  Back-patch
to v13 where the bug was introduced.

Discussion: https://postgr.es/m/136102.1648320427@sss.pgh.pa.us
2022-03-27 12:57:57 -04:00
Alvaro Herrera 50e3ed8e91
Fix replay of create database records on standby
Crash recovery on standby may encounter missing directories when
replaying create database WAL records.  Prior to this patch, the standby
would fail to recover in such a case.  However, the directories could be
legitimately missing.  Consider a sequence of WAL records as follows:

    CREATE DATABASE
    DROP DATABASE
    DROP TABLESPACE

If, after replaying the last WAL record and removing the tablespace
directory, the standby crashes and has to replay the create database
record again, the crash recovery must be able to move on.

This patch adds a mechanism similar to invalid-page tracking, to keep a
tally of missing directories during crash recovery.  If all the missing
directory references are matched with corresponding drop records at the
end of crash recovery, the standby can safely continue following the
primary.

Backpatch to 13, at least for now.  The bug is older, but fixing it in
older branches requires more careful study of the interactions with
commit e6d8069522, which appeared in 13.

A new TAP test file is added to verify the condition.  However, because
it depends on commit d6d317dbf6, it can only be added to branch
master.  I (Álvaro) manually verified that the code behaves as expected
in branch 14.  It's a bit nervous-making to leave the code uncovered by
tests in older branches, but leaving the bug unfixed is even worse.
Also, the main reason this fix took so long is precisely that we
couldn't agree on a good strategy to approach testing for the bug, so
perhaps this is the best we can do.

Diagnosed-by: Paul Guo <paulguo@gmail.com>
Author: Paul Guo <paulguo@gmail.com>
Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Author: Asim R Praveen <apraveen@pivotal.io>
Discussion: https://postgr.es/m/CAEET0ZGx9AvioViLf7nbR_8tH9-=27DN5xWJ2P9-ROH16e4JUA@mail.gmail.com
2022-03-25 13:16:21 +01:00
Robert Haas 1ce14b6b2f Fix possible recovery trouble if TRUNCATE overlaps a checkpoint.
If TRUNCATE causes some buffers to be invalidated and thus the
checkpoint does not flush them, TRUNCATE must also ensure that the
corresponding files are truncated on disk. Otherwise, a replay
from the checkpoint might find that the buffers exist but have
the wrong contents, which may cause replay to fail.

Report by Teja Mupparti. Patch by Kyotaro Horiguchi, per a design
suggestion from Heikki Linnakangas, with some changes to the
comments by me. Review of this and a prior patch that approached
the issue differently by Heikki Linnakangas, Andres Freund, Álvaro
Herrera, Masahiko Sawada, and Tom Lane.

Discussion: http://postgr.es/m/BYAPR06MB6373BF50B469CA393C614257ABF00@BYAPR06MB6373.namprd06.prod.outlook.com
2022-03-24 14:36:06 -04:00
Andres Freund c0f99bb520 Don't try to translate NULL in GetConfigOptionByNum().
Noticed via -fsanitize=undefined. Introduced when a few columns in
GetConfigOptionByNum() / pg_settings started to be translated in 72be8c29a /
PG 12.

Backpatch to all affected branches, for the same reasons as 46ab07ffda.

Discussion: https://postgr.es/m/20220323173537.ll7klrglnp4gn2um@alap3.anarazel.de
Backpatch: 12-
2022-03-23 13:18:00 -07:00
Andres Freund 8014c61ebd Don't call fwrite() with len == 0 when writing out relcache init file.
Noticed via -fsanitize=undefined.

Backpatch to all branches, for the same reasons as 46ab07ffda.

Discussion: https://postgr.es/m/20220323173537.ll7klrglnp4gn2um@alap3.anarazel.de
Backpatch: 10-
2022-03-23 13:13:20 -07:00
Alvaro Herrera 98eb3e06ce
Fix "missing continuation record" after standby promotion
Invalidate abortedRecPtr and missingContrecPtr after a missing
continuation record is successfully skipped on a standby. This fixes a
PANIC caused when a recently promoted standby attempts to write an
OVERWRITE_RECORD with an LSN of the previously read aborted record.

Backpatch to 10 (all stable versions).

Author: Sami Imseih <simseih@amazon.com>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/44D259DE-7542-49C4-8A52-2AB01534DCA9@amazon.com
2022-03-23 18:22:10 +01:00
Tom Lane dfefe38fbe Fix assorted missing logic for GroupingFunc nodes.
The planner needs to treat GroupingFunc like Aggref for many purposes,
in particular with respect to processing of the argument expressions,
which are not to be evaluated at runtime.  A few places hadn't gotten
that memo, notably including subselect.c's processing of outer-level
aggregates.  This resulted in assertion failures or wrong plans for
cases in which a GROUPING() construct references an outer aggregation
level.

Also fix missing special cases for GroupingFunc in cost_qual_eval
(resulting in wrong cost estimates for GROUPING(), although it's
not clear that that would affect plan shapes in practice) and in
ruleutils.c (resulting in excess parentheses in pretty-print mode).

Per bug #17088 from Yaoguang Chen.  Back-patch to all supported
branches.

Richard Guo, Tom Lane

Discussion: https://postgr.es/m/17088-e33882b387de7f5c@postgresql.org
2022-03-21 17:44:29 -04:00
Tom Lane 2241e5ceda Fix risk of deadlock failure while dropping a partitioned index.
DROP INDEX needs to lock the index's table before the index itself,
else it will deadlock against ordinary queries that acquire the
relation locks in that order.  This is correctly mechanized for
plain indexes by RangeVarCallbackForDropRelation; but in the case of
a partitioned index, we neglected to lock the child tables in advance
of locking the child indexes.  We can fix that by traversing the
inheritance tree and acquiring the needed locks in RemoveRelations,
after we have acquired our locks on the parent partitioned table and
index.

While at it, do some refactoring to eliminate confusion between
the actual and expected relkind in RangeVarCallbackForDropRelation.
We can save a couple of syscache lookups too, by having that function
pass back info that RemoveRelations will need.

Back-patch to v11 where partitioned indexes were added.

Jimmy Yih, Gaurab Dey, Tom Lane

Discussion: https://postgr.es/m/BYAPR05MB645402330042E17D91A70C12BD5F9@BYAPR05MB6454.namprd05.prod.outlook.com
2022-03-21 12:22:13 -04:00
Tom Lane 88ae77588d Fix incorrect xmlschema output for types timetz and timestamptz.
The output of table_to_xmlschema() and allied functions includes
a regex describing valid values for these types ... but the regex
was itself invalid, as it failed to escape a literal "+" sign.

Report and fix by Renan Soares Lopes.  Back-patch to all
supported branches.

Discussion: https://postgr.es/m/7f6fabaa-3f8f-49ab-89ca-59fbfe633105@me.com
2022-03-18 16:01:42 -04:00
Tom Lane 5e144cc89b Revert applying column aliases to the output of whole-row Vars.
In commit bf7ca1587, I had the bright idea that we could make the
result of a whole-row Var (that is, foo.*) track any column aliases
that had been applied to the FROM entry the Var refers to.  However,
that's not terribly logically consistent, because now the output of
the Var is no longer of the named composite type that the Var claims
to emit.  bf7ca1587 tried to handle that by changing the output
tuple values to be labeled with a blessed RECORD type, but that's
really pretty disastrous: we can wind up storing such tuples onto
disk, whereupon they're not readable by other sessions.

The only practical fix I can see is to give up on what bf7ca1587
tried to do, and say that the column names of tuples produced by
a whole-row Var are always those of the underlying named composite
type, query aliases or no.  While this introduces some inconsistencies,
it removes others, so it's not that awful in the abstract.  What *is*
kind of awful is to make such a behavioral change in a back-patched
bug fix.  But corrupt data is worse, so back-patched it will be.

(A workaround available to anyone who's unhappy about this is to
introduce an extra level of sub-SELECT, so that the whole-row Var is
referring to the sub-SELECT's output and not to a named table type.
Then the Var is of type RECORD to begin with and there's no issue.)

Per report from Miles Delahunty.  The faulty commit dates to 9.5,
so back-patch to all supported branches.

Discussion: https://postgr.es/m/2950001.1638729947@sss.pgh.pa.us
2022-03-17 18:18:05 -04:00
Tomas Vondra 27fafee72d Fix publish_as_relid with multiple publications
Commit 83fd4532a7 allowed publishing of changes via ancestors, for
publications defined with publish_via_partition_root. But the way
the ancestor was determined in get_rel_sync_entry() was incorrect,
simply updating the same variable. So with multiple publications,
replicating different ancestors, the outcome depended on the order
of publications in the list - the value from the last loop was used,
even if it wasn't the top-most ancestor.

This is a probably rare situation, as in most cases publications do
not overlap, so each partition has exactly one candidate ancestor
to replicate as and there's no ambiguity.

Fixed by tracking the "ancestor level" for each publication, and
picking the top-most ancestor. Adds a test case, verifying the
correct ancestor is used for publishing the changes and that this
does not depend on order of publications in the list.

Older releases have another bug in this loop - once all actions are
replicated, the loop is terminated, on the assumption that inspecting
additional publications is unecessary. But that misses the fact that
those additional applications may replicate different ancestors.

Fixed by removal of this break condition. We might still terminate the
loop in some cases (e.g. when replicating all actions and the ancestor
is the partition root).

Backpatch to 13, where publish_via_partition_root was introduced.

Initial report and fix by me, test added by Hou zj. Reviews and
improvements by Amit Kapila.

Author: Tomas Vondra, Hou zj, Amit Kapila
Reviewed-by: Amit Kapila, Hou zj
Discussion: https://postgr.es/m/d26d24dd-2fab-3c48-0162-2b7f84a9c893%40enterprisedb.com
2022-03-16 18:14:33 +01:00
Thomas Munro 51e760e5a6 Fix race between DROP TABLESPACE and checkpointing.
Commands like ALTER TABLE SET TABLESPACE may leave files for the next
checkpoint to clean up.  If such files are not removed by the time DROP
TABLESPACE is called, we request a checkpoint so that they are deleted.
However, there is presently a window before checkpoint start where new
unlink requests won't be scheduled until the following checkpoint.  This
means that the checkpoint forced by DROP TABLESPACE might not remove the
files we expect it to remove, and the following ERROR will be emitted:

	ERROR:  tablespace "mytblspc" is not empty

To fix, add a call to AbsorbSyncRequests() just before advancing the
unlink cycle counter.  This ensures that any unlink requests forwarded
prior to checkpoint start (i.e., when ckpt_started is incremented) will
be processed by the current checkpoint.  Since AbsorbSyncRequests()
performs memory allocations, it cannot be called within a critical
section, so we also need to move SyncPreCheckpoint() to before
CreateCheckPoint()'s critical section.

This is an old bug, so back-patch to all supported versions.

Author: Nathan Bossart <nathandbossart@gmail.com>
Reported-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20220215235845.GA2665318%40nathanxps13
2022-03-16 17:21:19 +13:00
Thomas Munro cfdb303be7 Fix waiting in RegisterSyncRequest().
If we run out of space in the checkpointer sync request queue (which is
hopefully rare on real systems, but common with very small buffer pool),
we wait for it to drain.  While waiting, we should report that as a wait
event so that users know what is going on, and also handle postmaster
death, since otherwise the loop might never terminate if the
checkpointer has exited.

Back-patch to 12.  Although the problem exists in earlier releases too,
the code is structured differently before 12 so I haven't gone any
further for now, in the absence of field complaints.

Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20220226213942.nb7uvb2pamyu26dj%40alap3.anarazel.de
2022-03-16 15:37:15 +13:00
Thomas Munro 5610411ac7 Back-patch LLVM 14 API changes.
Since LLVM 14 has stopped changing and is about to be released,
back-patch the following changes from the master branch:

  e6a7600202
  807fee1a39
  a56e7b6601

Back-patch to 11, where LLVM JIT support came in.
2022-03-16 11:41:13 +13:00
Tom Lane 1a027e6b7b Clean up assorted failures under clang's -fsanitize=undefined checks.
Most of these are cases where we could call memcpy() or other libc
functions with a NULL pointer and a zero count, which is forbidden
by POSIX even though every production version of libc allows it.
We've fixed such things before in a piecemeal way, but apparently
never made an effort to try to get them all.  I don't claim that
this patch does so either, but it gets every failure I observe in
check-world, using clang 12.0.1 on current RHEL8.

numeric.c has a different issue that the sanitizer doesn't like:
"ln(-1.0)" will compute log10(0) and then try to assign the
resulting -Inf to an integer variable.  We don't actually use the
result in such a case, so there's no live bug.

Back-patch to all supported branches, with the idea that we might
start running a buildfarm member that tests this case.  This includes
back-patching c1132aae3 (Check the size in COPY_POINTER_FIELD),
which previously silenced some of these issues in copyfuncs.c.

Discussion: https://postgr.es/m/CALNJ-vT9r0DSsAOw9OXVJFxLENoVS_68kJ5x0p44atoYH+H4dg@mail.gmail.com
2022-03-03 18:13:24 -05:00
Tom Lane 6599d8f126 Allow root-owned SSL private keys in libpq, not only the backend.
This change makes libpq apply the same private-key-file ownership
and permissions checks that we have used in the backend since commit
9a83564c5.  Namely, that the private key can be owned by either the
current user or root (with different file permissions allowed in the
two cases).  This allows system-wide management of key files, which
is just as sensible on the client side as the server, particularly
when the client is itself some application daemon.

Sync the comments about this between libpq and the backend, too.

Back-patch of a59c79564 and 50f03473e into all supported branches.

David Steele

Discussion: https://postgr.es/m/f4b7bc55-97ac-9e69-7398-335e212f7743@pgmasters.net
2022-03-02 11:57:02 -05:00
Andres Freund c2551483e0 Fix temporary object cleanup failing due to toast access without snapshot.
When cleaning up temporary objects during process exit the cleanup could fail
with:
  FATAL: cannot fetch toast data without an active snapshot

The bug is caused by RemoveTempRelationsCallback() not setting up a
snapshot. If an object with toasted catalog data needs to be cleaned up,
init_toast_snapshot() could fail with the above error.

Most of the time however the the problem is masked due to cached catalog
snapshots being returned by GetOldestSnapshot(). But dropping an object can
cause catalog invalidations to be emitted. If no further catalog accesses are
necessary between the invalidation processing and the next toast datum
deletion, the bug becomes visible.

It's easy to miss this bug because it typically happens after clients
disconnect and the FATAL error just ends up in the log.

Luckily temporary table cleanup at the next use of the same temporary schema
or during DISCARD ALL does not have the same problem.

Fix the bug by pushing a snapshot in RemoveTempRelationsCallback(). Also add
isolation tests for temporary object cleanup, including objects with toasted
catalog data.

A future HEAD only commit will add more assertions.

Reported-By: Miles Delahunty
Author: Andres Freund
Discussion: https://postgr.es/m/CAOFAq3BU5Mf2TTvu8D9n_ZOoFAeQswuzk7yziAb7xuw_qyw5gw@mail.gmail.com
Backpatch: 10-
2022-02-21 08:59:30 -08:00
Tom Lane 46b738ffc2 Suppress warning about stack_base_ptr with late-model GCC.
GCC 12 complains that set_stack_base is storing the address of
a local variable in a long-lived pointer.  This is an entirely
reasonable warning (indeed, it just helped us find a bug);
but that behavior is intentional here.  We can work around it
by using __builtin_frame_address(0) instead of a specific local
variable; that produces an address a dozen or so bytes different,
in my testing, but we don't care about such a small difference.
Maybe someday a compiler lacking that function will start to issue
a similar warning, but we'll worry about that when it happens.

Patch by me, per a suggestion from Andres Freund.  Back-patch to
v12, which is as far back as the patch will go without some pain.
(Recently-established project policy would permit a back-patch as
far as 9.2, but I'm disinclined to expend the work until GCC 12
is much more widespread.)

Discussion: https://postgr.es/m/3773792.1645141467@sss.pgh.pa.us
2022-02-17 22:45:34 -05:00
Amit Kapila caa231be97 WAL log unchanged toasted replica identity key attributes.
Currently, during UPDATE, the unchanged replica identity key attributes
are not logged separately because they are getting logged as part of the
new tuple. But if they are stored externally then the untoasted values are
not getting logged as part of the new tuple and logical replication won't
be able to replicate such UPDATEs. So we need to log such attributes as
part of the old_key_tuple during UPDATE.

Reported-by: Haiying Tang
Author: Dilip Kumar and Amit Kapila
Reviewed-by: Alvaro Herrera, Haiying Tang, Andres Freund
Backpatch-through: 10
Discussion: https://postgr.es/m/OS0PR01MB611342D0A92D4F4BF26C0F47FB229@OS0PR01MB6113.jpnprd01.prod.outlook.com
2022-02-14 08:24:44 +05:30
Alexander Korotkov ac2303aa03 Fix memory leak in IndexScan node with reordering
Fix ExecReScanIndexScan() to free the referenced tuples while emptying the
priority queue.  Backpatch to all supported versions.

Discussion: https://postgr.es/m/CAHqSB9gECMENBQmpbv5rvmT3HTaORmMK3Ukg73DsX5H7EJV7jw%40mail.gmail.com
Author: Aliaksandr Kalenik
Reviewed-by: Tom Lane, Alexander Korotkov
Backpatch-through: 10
2022-02-14 03:32:34 +03:00
Tom Lane 0778b24ced Don't use_physical_tlist for an IOS with non-returnable columns.
createplan.c tries to save a runtime projection step by specifying
a scan plan node's output as being exactly the table's columns, or
index's columns in the case of an index-only scan, if there is not a
reason to do otherwise.  This logic did not previously pay attention
to whether an index's columns are returnable.  That worked, sort of
accidentally, until commit 9a3ddeb51 taught setrefs.c to reject plans
that try to read a non-returnable column.  I have no desire to loosen
setrefs.c's new check, so instead adjust use_physical_tlist() to not
try to optimize this way when there are non-returnable column(s).

Per report from Ryan Kelly.  Like the previous patch, back-patch
to all supported branches.

Discussion: https://postgr.es/m/CAHUie24ddN+pDNw7fkhNrjrwAX=fXXfGZZEHhRuofV_N_ftaSg@mail.gmail.com
2022-02-11 15:23:52 -05:00
Noah Misch 1b8462bf1d Fix back-patch of "Avoid race in RelationBuildDesc() ..."
The back-patch of commit fdd965d074 broke
CLOBBER_CACHE_ALWAYS for v9.6 through v13.  It updated the
InvalidateSystemCaches() call for CLOBBER_CACHE_RECURSIVELY, neglecting
the one for CLOBBER_CACHE_ALWAYS.  Back-patch to v13, v12, v11, and v10.

Reviewed by Tomas Vondra.  Reported by Tomas Vondra.

Discussion: https://postgr.es/m/df7b4c0b-7d92-f03f-75c4-9e08b269a716@enterprisedb.com
2022-02-09 18:16:56 -08:00
Peter Eisentraut 7f7148b72e Translation updates
Source-Git-URL: git://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: 9aa8bc576f9af5c61de4a6fc8119abfa36493d01
2022-02-07 13:36:22 +01:00
Tom Lane 9c7cf083f2 Test, don't just Assert, that mergejoin's inputs are in order.
There are two Asserts in nodeMergejoin.c that are reachable if
the input data is not in the expected order.  This seems way too
fragile.  Alexander Lakhin reported a case where the assertions
could be triggered with misconfigured foreign-table partitions,
and bitter experience with unstable operating system collation
definitions suggests another easy route to hitting them.  Neither
Assert is in a place where we can't afford one more test-and-branch,
so replace 'em with plain test-and-elog logic.

Per bug #17395.  While the reported symptom is relatively recent,
collation changes could happen anytime, so back-patch to all
supported branches.

Discussion: https://postgr.es/m/17395-8c326292078d1a57@postgresql.org
2022-02-05 11:59:30 -05:00
Tom Lane 5ad70564f4 Fix failure to validate the result of select_common_type().
Although select_common_type() has a failure-return convention, an
apparent successful return just provides a type OID that *might* work
as a common supertype; we've not validated that the required casts
actually exist.  In the mainstream use-cases that doesn't matter,
because we'll proceed to invoke coerce_to_common_type() on each input,
which will fail appropriately if the proposed common type doesn't
actually work.  However, a few callers didn't read the (nonexistent)
fine print, and thought that if they got back a nonzero OID then the
coercions were sure to work.

This affects in particular the recently-added "anycompatible"
polymorphic types; we might think that a function/operator using
such types matches cases it really doesn't.  A likely end result
of that is unexpected "ambiguous operator" errors, as for example
in bug #17387 from James Inform.  Another, much older, case is that
the parser might try to transform an "x IN (list)" construct to
a ScalarArrayOpExpr even when the list elements don't actually have
a common supertype.

It doesn't seem desirable to add more checking to select_common_type
itself, as that'd just slow down the mainstream use-cases.  Instead,
write a separate function verify_common_type that performs the
missing checks, and add a call to that where necessary.  Likewise add
verify_common_type_from_oids to go with select_common_type_from_oids.

Back-patch to v13 where the "anycompatible" types came in.  (The
symptom complained of in bug #17387 doesn't appear till v14, but
that's just because we didn't get around to converting || to use
anycompatible till then.)  In principle the "x IN (list)" fix could
go back all the way, but I'm not currently convinced that it makes
much difference in real-world cases, so I won't bother for now.

Discussion: https://postgr.es/m/17387-5dfe54b988444963@postgresql.org
2022-01-29 11:41:12 -05:00
Tomas Vondra e90f258aca Fix ordering of XIDs in ProcArrayApplyRecoveryInfo
Commit 8431e296ea reworked ProcArrayApplyRecoveryInfo to sort XIDs
before adding them to KnownAssignedXids. But the XIDs are sorted using
xidComparator, which compares the XIDs simply as uint32 values, not
logically. KnownAssignedXidsAdd() however expects XIDs in logical order,
and calls TransactionIdFollowsOrEquals() to enforce that. If there are
XIDs for which the two orderings disagree, an error is raised and the
recovery fails/restarts.

Hitting this issue is fairly easy - you just need two transactions, one
started before the 4B limit (e.g. XID 4294967290), the other sometime
after it (e.g. XID 1000). Logically (4294967290 <= 1000) but when
compared using xidComparator we try to add them in the opposite order.
Which makes KnownAssignedXidsAdd() fail with an error like this:

  ERROR: out-of-order XID insertion in KnownAssignedXids

This only happens during replica startup, while processing RUNNING_XACTS
records to build the snapshot. Once we reach STANDBY_SNAPSHOT_READY, we
skip these records. So this does not affect already running replicas,
but if you restart (or create) a replica while there are transactions
with XIDs for which the two orderings disagree, you may hit this.

Long-running transactions and frequent replica restarts increase the
likelihood of hitting this issue. Once the replica gets into this state,
it can't be started (even if the old transactions are terminated).

Fixed by sorting the XIDs logically - this is fine because we're dealing
with normal XIDs (because it's XIDs assigned to backends) and from the
same wraparound epoch (otherwise the backends could not be running at
the same time on the primary node). So there are no problems with the
triangle inequality, which is why xidComparator compares raw values.

Investigation and root cause analysis by Abhijit Menon-Sen. Patch by me.

This issue is present in all releases since 9.4, however releases up to
9.6 are EOL already so backpatch to 10 only.

Reviewed-by: Abhijit Menon-Sen
Reviewed-by: Alvaro Herrera
Backpatch-through: 10
Discussion: https://postgr.es/m/36b8a501-5d73-277c-4972-f58a4dce088a%40enterprisedb.com
2022-01-27 20:16:39 +01:00
Magnus Hagander 81596645ca Fix pg_hba_file_rules for authentication method cert
For authentication method cert, clientcert=verify-full is implied. But
the pg_hba_file_rules entry would incorrectly show clientcert=verify-ca.

Per bug #17354

Reported-By: Feike Steenbergen
Reviewed-By: Jonathan Katz
Backpatch-through: 12
2022-01-26 09:59:19 +01:00
Tom Lane 213c5aa3bd Revert "graceful shutdown" changes for Windows, in back branches only.
This reverts commits 6051857fc and ed52c3707, but only in the back
branches.  Further testing has shown that while those changes do fix
some things, they also break others; in particular, it looks like
walreceivers fail to detect walsender-initiated connection close
reliably if the walsender shuts down this way.  We'll keep trying to
improve matters in HEAD, but it now seems unwise to push these changes
into stable releases.

Discussion: https://postgr.es/m/CA+hUKG+OeoETZQ=Qw5Ub5h3tmwQhBmDA=nuNO3KG=zWfUypFAw@mail.gmail.com
2022-01-25 12:17:40 -05:00
David Rowley f8807e7742 Consider parallel awareness when removing single-child Appends
8edd0e794 added some code to remove Append and MergeAppend nodes when they
contained a single child node.  As it turned out, this was unsafe to do
when the Append/MergeAppend was parallel_aware and the child node was not.
Removing the Append/MergeAppend, in this case, could lead to the child plan
being called multiple times by parallel workers when it was unsafe to do
so.

Here we fix this by just not removing the Append/MergeAppend when the
parallel_aware flag of the parent and child node don't match.

Reported-by: Yura Sokolov
Bug: #17335
Discussion: https://postgr.es/m/b59605fecb20ba9ea94e70ab60098c237c870628.camel%40postgrespro.ru
Backpatch-through: 12, where 8edd0e794 was first introduced
2022-01-25 21:15:00 +13:00
Tom Lane d67354d870 Fix limitations on what SQL commands can be issued to a walsender.
In logical replication mode, a WalSender is supposed to be able
to execute any regular SQL command, as well as the special
replication commands.  Poor design of the replication-command
parser caused it to fail in various cases, notably:

* semicolons embedded in a command, or multiple SQL commands
sent in a single message;

* dollar-quoted literals containing odd numbers of single
or double quote marks;

* commands starting with a comment.

The basic problem here is that we're trying to run repl_scanner.l
across the entire input string even when it's not a replication
command.  Since repl_scanner.l does not understand all of the
token types known to the core lexer, this is doomed to have
failure modes.

We certainly don't want to make repl_scanner.l as big as scan.l,
so instead rejigger stuff so that we only lex the first token of
a non-replication command.  That will usually look like an IDENT
to repl_scanner.l, though a comment would end up getting reported
as a '-' or '/' single-character token.  If the token is a replication
command keyword, we push it back and proceed normally with repl_gram.y
parsing.  Otherwise, we can drop out of exec_replication_command()
without examining the rest of the string.

(It's still theoretically possible for repl_scanner.l to fail on
the first token; but that could only happen if it's an unterminated
single- or double-quoted string, in which case you'd have gotten
largely the same error from the core lexer too.)

In this way, repl_gram.y isn't involved at all in handling general
SQL commands, so we can get rid of the SQLCmd node type.  (In
the back branches, we can't remove it because renumbering enum
NodeTag would be an ABI break; so just leave it sit there unused.)

I failed to resist the temptation to clean up some other sloppy
coding in repl_scanner.l while at it.  The only externally-visible
behavior change from that is it now accepts \r and \f as whitespace,
same as the core lexer.

Per bug #17379 from Greg Rychlewski.  Back-patch to all supported
branches.

Discussion: https://postgr.es/m/17379-6a5c6cfb3f1f5e77@postgresql.org
2022-01-24 15:33:34 -05:00
Tom Lane c94c6612da Remember to reset yy_start state when firing up repl_scanner.l.
Without this, we get odd behavior when the previous cycle of
lexing exited in a non-default exclusive state.  Every other
copy of this code is aware that it has to do BEGIN(INITIAL),
but repl_scanner.l did not get that memo.

The real-world impact of this is probably limited, since most
replication clients would abandon their connection after getting
a syntax error.  Still, it's a bug.

This mistake is old, so back-patch to all supported branches.

Discussion: https://postgr.es/m/1874781.1643035952@sss.pgh.pa.us
2022-01-24 12:09:46 -05:00
Tom Lane 0cbc507378 Suppress variable-set-but-not-used warning from clang 13.
In the normal configuration where GEQO_DEBUG isn't defined,
recent clang versions have started to complain that geqo_main.c
accumulates the edge_failures count but never does anything
with it.  As a minimal back-patchable fix, insert a void cast
to silence this warning.  (I'd speculated about ripping out the
GEQO_DEBUG logic altogether, but I don't think we'd wish to
back-patch that.)

Per recently-established project policy, this is a candidate
for back-patching into out-of-support branches: it suppresses
an annoying compiler warning but changes no behavior.  Hence,
back-patch all the way to 9.2.

Discussion: https://postgr.es/m/CA+hUKGLTSZQwES8VNPmWO9AO0wSeLt36OCPDAZTccT1h7Q7kTQ@mail.gmail.com
2022-01-23 11:09:25 -05:00
Tomas Vondra 4d8c4d2061 Correct type of front_pathkey to PathKey
In sort_inner_and_outer we iterate a list of PathKey elements, but the
variable is declared as (List *). This mistake is benign, because we
only pass the pointer to lcons() and never dereference it.

This exists since ~2004, but it's confusing. So fix and backpatch to all
supported branches.

Backpatch-through: 10
Discussion: https://postgr.es/m/bf3a6ea1-a7d8-7211-0669-189d5c169374%40enterprisedb.com
2022-01-23 04:02:22 +01:00
Tomas Vondra 267ccc38ba Check syscache result in AlterStatistics
The syscache lookup may return NULL even for valid OID, for example due
to a concurrent DROP STATISTICS, so a HeapTupleIsValid is necessary.
Without it, it may fail with a segfault.

Reported by Alexander Lakhin, patch by me. Backpatch to 13, where ALTER
STATISTICS ... SET STATISTICS was introduced.

Backpatch-through: 13
Discussion: https://postgr.es/m/17372-bf3b6e947e35ae77%40postgresql.org
2022-01-23 03:20:32 +01:00
Tom Lane 31b7b4d26e Flush table's relcache during ALTER TABLE ADD PRIMARY KEY USING INDEX.
Previously, unless we had to add a NOT NULL constraint to the column,
this command resulted in updating only the index's relcache entry.
That's problematic when replication behavior is being driven off the
existence of a primary key: other sessions (and ours too for that
matter) failed to recalculate their opinion of whether the table can
be replicated.  Add a relcache invalidation to fix it.

This has been broken since pg_class.relhaspkey was removed in v11.
Before that, updating the table's relhaspkey value sufficed to cause
a cache flush.  Hence, backpatch to v11.

Report and patch by Hou Zhijie

Discussion: https://postgr.es/m/OS0PR01MB5716EBE01F112C62F8F9B786947B9@OS0PR01MB5716.jpnprd01.prod.outlook.com
2022-01-22 13:32:40 -05:00
Andres Freund fd48e5f5d3 fsync pg_logical/mappings in CheckPointLogicalRewriteHeap().
While individual logical rewrite files were synced to disk, the directory was
not. On some filesystems that could lead to loosing directory entries after a
crash.

Reported-By: Tom Lane <tgl@sss.pgh.pa.us>
Author: Nathan Bossart <bossartn@amazon.com>
Discussion: https://postgr.es/m/867F2E29-2782-4869-970E-B984C6D35A8F@amazon.com
Backpatch: 10-
2022-01-21 11:24:12 -08:00
Michael Paquier b5f634116e Fix one-off bug causing missing commit timestamps for subtransactions
The logic in charge of writing commit timestamps (enabled with
track_commit_timestamp) for subtransactions had a one-bug bug,
where it would be possible that commit timestamps go missing for the
last subtransaction committed.

While on it, simplify a bit the iteration logic in the loop writing the
commit timestamps, as per suggestions from Kyotaro Horiguchi and Tom
Lane, so as some variable initializations are not part of the loop
itself.

Issue introduced in 73c986a.

Analyzed-by: Alex Kingsborough
Author: Alex Kingsborough, Kyotaro Horiguchi
Discussion: https://postgr.es/m/73A66172-4050-4F2A-B7F1-13508EDA2144@amazon.com
Backpatch-through: 10
2022-01-21 14:54:51 +09:00
Tomas Vondra d6817032d2 Build inherited extended stats on partitioned tables
Commit 859b3003de disabled building of extended stats for inheritance
trees, to prevent updating the same catalog row twice. While that
resolved the issue, it also means there are no extended stats for
declaratively partitioned tables, because there are no data in the
non-leaf relations.

That also means declaratively partitioned tables were not affected by
the issue 859b3003de addressed, which means this is a regression
affecting queries that calculate estimates for the whole inheritance
tree as a whole (which includes e.g. GROUP BY queries).

But because partitioned tables are empty, we can invert the condition
and build statistics only for the case with inheritance, without losing
anything. And we can consider them when calculating estimates.

It may be necessary to run ANALYZE on partitioned tables, to collect
proper statistics. For declarative partitioning there should no prior
statistics, and it might take time before autoanalyze is triggered. For
tables partitioned by inheritance the statistics may include data from
child relations (if built 859b3003de), contradicting the current code.

Report and patch by Justin Pryzby, minor fixes and cleanup by me.
Backpatch all the way back to PostgreSQL 10, where extended statistics
were introduced (same as 859b3003de).

Author: Justin Pryzby
Reported-by: Justin Pryzby
Backpatch-through: 10
Discussion: https://postgr.es/m/20210923212624.GI831%40telsasoft.com
2022-01-15 19:14:00 +01:00
Tomas Vondra acfde7c583 Ignore extended statistics for inheritance trees
Since commit 859b3003de we only build extended statistics for individual
relations, ignoring the child relations. This resolved the issue with
updating catalog tuple twice, but we still tried to use the statistics
when calculating estimates for the whole inheritance tree. When the
relations contain very distinct data, it may produce bogus estimates.

This is roughly the same issue 427c6b5b9 addressed ~15 years ago, and we
fix it the same way - by ignoring extended statistics when calculating
estimates for the inheritance tree as a whole. We still consider
extended statistics when calculating estimates for individual child
relations, of course.

This may result in plan changes due to different estimates, but if the
old statistics were not describing the inheritance tree particularly
well it's quite likely the new plans is actually better.

Report and patch by Justin Pryzby, minor fixes and cleanup by me.
Backpatch all the way back to PostgreSQL 10, where extended statistics
were introduced (same as 859b3003de).

Author: Justin Pryzby
Reported-by: Justin Pryzby
Backpatch-through: 10
Discussion: https://postgr.es/m/20210923212624.GI831%40telsasoft.com
2022-01-15 02:30:06 +01:00
Tom Lane ca14c4184b Fix ruleutils.c's dumping of whole-row Vars in more contexts.
Commit 7745bc352 intended to ensure that whole-row Vars would be
printed with "::type" decoration in all contexts where plain
"var.*" notation would result in star-expansion, notably in
ROW() and VALUES() constructs.  However, it missed the case of
INSERT with a single-row VALUES, as reported by Timur Khanjanov.

Nosing around ruleutils.c, I found a second oversight: the
code for RowCompareExpr generates ROW() notation without benefit
of an actual RowExpr, and naturally it wasn't in sync :-(.
(The code for FieldStore also does this, but we don't expect that
to generate strictly parsable SQL anyway, so I left it alone.)

Back-patch to all supported branches.

Discussion: https://postgr.es/m/efaba6f9-4190-56be-8ff2-7a1674f9194f@intrans.baku.az
2022-01-13 17:49:26 -05:00
Tom Lane 86d4bbb56a Prevent altering partitioned table's rowtype, if it's used elsewhere.
We disallow altering a column datatype within a regular table,
if the table's rowtype is used as a column type elsewhere,
because we lack code to go around and rewrite the other tables.
This restriction should apply to partitioned tables as well, but it
was not checked because ATRewriteTables and ATPrepAlterColumnType
were not on the same page about who should do it for which relkinds.

Per bug #17351 from Alexander Lakhin.  Back-patch to all supported
branches.

Discussion: https://postgr.es/m/17351-6db1870f3f4f612a@postgresql.org
2022-01-06 16:46:46 -05:00
Michael Paquier 3f8062bcf7 Reduce relcache access in WAL sender streaming logical changes
get_rel_sync_entry(), which is called each time a change needs to be
logically replicated, is a rather hot code path in the WAL sender
sending logical changes.  This code path was doing a relcache access on
relkind and relpartition for each logical change, but we only need to
know this information when building or re-building the cached
information for a relation.

Some measurements prove that this is noticeable in perf profiles,
particularly when attempting to replicate changes from relations that
are not published as these cause less overhead in the WAL sender,
delaying further the replication of changes for relations that are
published.

Issue introduced in 83fd453.

Author: Hou Zhijie
Reviewed-by: Kyotaro Horiguchi, Euler Taveira
Discussion: https://postgr.es/m/OS0PR01MB5716E863AA9E591C1F010F7A947D9@OS0PR01MB5716.jpnprd01.prod.outlook.com
Backpatch-through: 13
2022-01-05 10:27:53 +09:00
Alvaro Herrera 33fdd9f854
Fix silly mistake in Assert 2022-01-04 13:21:23 -03:00
Alvaro Herrera 29f9fb8fe8
Allow special SKIP LOCKED condition in Assert()
Under concurrency, it is possible for two sessions to be merrily locking
and releasing a tuple and marking it again as HEAP_XMAX_INVALID all the
while a third session attempts to lock it, miserably fails at it, and
then contemplates life, the universe and everything only to eventually
fail an assertion that said bit is not set.  Before SKIP LOCKED that was
indeed a reasonable expectation, but alas! commit df630b0dd5 falsified
it.

This bug is as old as time itself, and even older, if you think time
begins with the oldest supported branch.  Therefore, backpatch to all
supported branches.

Author: Simon Riggs <simon.riggs@enterprisedb.com>
Discussion: https://postgr.es/m/CANbhV-FeEwMnN8yuMyss7if1ZKjOKfjcgqB26n8pqu1e=q0ebg@mail.gmail.com
2022-01-04 13:01:05 -03:00
Tom Lane 20d08b2c61 Fix index-only scan plans, take 2.
Commit 4ace45677 failed to fix the problem fully, because the
same issue of attempting to fetch a non-returnable index column
can occur when rechecking the indexqual after using a lossy index
operator.  Moreover, it broke EXPLAIN for such indexquals (which
indicates a gap in our test cases :-().

Revert the code changes of 4ace45677 in favor of adding a new field
to struct IndexOnlyScan, containing a version of the indexqual that
can be executed against the index-returned tuple without using any
non-returnable columns.  (The restrictions imposed by check_index_only
guarantee this is possible, although we may have to recompute indexed
expressions.)  Support construction of that during setrefs.c
processing by marking IndexOnlyScan.indextlist entries as resjunk
if they can't be returned, rather than removing them entirely.
(We could alternatively require setrefs.c to look up the IndexOptInfo
again, but abusing resjunk this way seems like a reasonably safe way
to avoid needing to do that.)

This solution isn't great from an API-stability standpoint: if there
are any extensions out there that build IndexOnlyScan structs directly,
they'll be broken in the next minor releases.  However, only a very
invasive extension would be likely to do such a thing.  There's no
change in the Path representation, so typical planner extensions
shouldn't have a problem.

As before, back-patch to all supported branches.

Discussion: https://postgr.es/m/3179992.1641150853@sss.pgh.pa.us
Discussion: https://postgr.es/m/17350-b5bdcf476e5badbb@postgresql.org
2022-01-03 15:42:27 -05:00
Tom Lane 45ae427141 Fix index-only scan plans when not all index columns can be returned.
If an index has both returnable and non-returnable columns, and one of
the non-returnable columns is an expression using a Var that is in a
returnable column, then a query returning that expression could result
in an index-only scan plan that attempts to read the non-returnable
column, instead of recomputing the expression from the returnable
column as intended.

To fix, redefine the "indextlist" list of an IndexOnlyScan plan node
as containing null Consts in place of any non-returnable columns.
This solves the problem by preventing setrefs.c from falsely matching
to such entries.  The executor is happy since it only cares about the
exposed types of the entries, and ruleutils.c doesn't care because a
correct plan won't reference those entries.  I considered some other
ways to prevent setrefs.c from doing the wrong thing, but this way
seems good since (a) it allows a very localized fix, (b) it makes
the indextlist structure more compact in many cases, and (c) the
indextlist is now a more faithful representation of what the index AM
will actually produce, viz. nulls for any non-returnable columns.

This is easier to hit since we introduced included columns, but it's
possible to construct failing examples without that, as per the
added regression test.  Hence, back-patch to all supported branches.

Per bug #17350 from Louis Jachiet.

Discussion: https://postgr.es/m/17350-b5bdcf476e5badbb@postgresql.org
2022-01-01 16:12:03 -05:00
Tom Lane da0d8a4545 Ensure casting to typmod -1 generates a RelabelType.
Fix the code changed by commit 5c056b0c2 so that we always generate
RelabelType, not something else, for a cast to unspecified typmod.
Otherwise planner optimizations might not happen.

It appears we missed this point because the previous experiments were
done on type numeric: the parser undesirably generates a call on the
numeric() length-coercion function, but then numeric_support()
optimizes that down to a RelabelType, so that everything seems fine.
It misbehaves for types that have a non-optimized length coercion
function, such as bpchar.

Per report from John Naylor.  Back-patch to all supported branches,
as the previous patch eventually was.  Unfortunately, that no longer
includes 9.6 ... we really shouldn't put this type of change into a
nearly-EOL branch.

Discussion: https://postgr.es/m/CAFBsxsEfbFHEkouc+FSj+3K1sHipLPbEC67L0SAe-9-da8QtYg@mail.gmail.com
2021-12-16 15:36:02 -05:00
Tom Lane 0a5682041d Fix datatype confusion in logtape.c's right_offset().
This could only matter if (a) long is wider than int, and (b) the heap
of free blocks exceeds UINT_MAX entries, which seems pretty unlikely.
Still, it's a theoretical bug, so backpatch to v13 where the typo came
in (in commit c02fdc922).

In passing, also make swap_nodes() use consistent datatypes.

Ma Liangzhu

Discussion: https://postgr.es/m/17336-fc4e522d26a750fd@postgresql.org
2021-12-14 11:46:48 -05:00
Michael Paquier 3f710fc2b4 Remove assertion for replication origins in PREPARE TRANSACTION
When using replication origins, pg_replication_origin_xact_setup() is an
optional choice to be able to set a LSN and a timestamp to mark the
origin, which would be additionally added to WAL for transaction commits
or aborts (including 2PC transactions).  An assertion in the code path
of PREPARE TRANSACTION assumed that this data should always be set, so
it would trigger when using replication origins without setting up an
origin LSN.  Some tests are added to cover more this kind of scenario.

Oversight in commit 1eb6d65.

Per discussion with Amit Kapila and Masahiko Sawada.

Discussion: https://postgr.es/m/YbbBfNSvMm5nIINV@paquier.xyz
Backpatch-through: 11
2021-12-14 10:58:29 +09:00
Amit Kapila 3f06c00cf6 Fix double publish of child table's data.
We publish the child table's data twice for a publication that has both
child and parent tables and is published with publish_via_partition_root
as true. This happens because subscribers will initiate synchronization
using both parent and child tables, since it gets both as separate tables
in the initial table list.

Ensure that pg_publication_tables returns only parent tables in such
cases.

Author: Hou Zhijie
Reviewed-by: Greg Nancarrow, Amit Langote, Vignesh C, Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/OS0PR01MB57167F45D481F78CDC5986F794B99@OS0PR01MB5716.jpnprd01.prod.outlook.com
2021-12-09 09:00:35 +05:30
Michael Paquier 9acea52ea3 Fix corruption of toast indexes with REINDEX CONCURRENTLY
REINDEX CONCURRENTLY run on a toast index or a toast relation could
corrupt the target indexes rebuilt, as a backend running in parallel
that manipulates toast values would directly release the lock on the
toast relation when its local operation is done, rather than releasing
the lock once the transaction that manipulated the toast values
committed.

The fix done here is simple: we now hold a ROW EXCLUSIVE lock on the
toast relation when saving or deleting a toast value until the
transaction working on them is committed, so as a concurrent reindex
happening in parallel would be able to wait for any activity and see any
new rows inserted (or deleted).

An isolation test is added to check after the case fixed here, which is
a bit fancy by design as it relies on allow_system_table_mods to rename
the toast table and its index to fixed names.  This way, it is possible
to reindex them directly without any dependency on the OID of the
underlying relation.  Note that this could not use a DO block either, as
REINDEX CONCURRENTLY cannot be run in a transaction block.  The test is
backpatched down to 13, where it is possible, thanks to c4a7a39, to use
allow_system_table_mods in a test suite.

Reported-by: Alexey Ermakov
Analyzed-by: Andres Freund, Noah Misch
Author: Michael Paquier
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/17268-d2fb426e0895abd4@postgresql.org
Backpatch-through: 12
2021-12-08 11:01:19 +09:00
Tom Lane a8a983e829 On Windows, also call shutdown() while closing the client socket.
Further experimentation shows that commit 6051857fc is not sufficient
when using (some versions of?) OpenSSL.  The reason is obscure, but
calling shutdown(socket, SD_SEND) improves matters.

Per testing by Andrew Dunstan and Alexander Lakhin.
Back-patch as before.

Discussion: https://postgr.es/m/af5e0bf3-6a61-bb97-6cba-061ddf22ff6b@dunslane.net
2021-12-07 13:34:19 -05:00
Tom Lane 6251f86241 On Windows, close the client socket explicitly during backend shutdown.
It turns out that this is necessary to keep Winsock from dropping any
not-yet-sent data, such as an error message explaining the reason for
process termination.  It's pretty weird that the implicit close done
by the kernel acts differently from an explicit close, but it's hard
to argue with experimental results.

Independently submitted by Alexander Lakhin and Lars Kanis (comments
by me, though).  Back-patch to all supported branches.

Discussion: https://postgr.es/m/90b34057-4176-7bb0-0dbb-9822a5f6425b@greiz-reinsdorf.de
Discussion: https://postgr.es/m/16678-253e48d34dc0c376@postgresql.org
2021-12-02 17:15:01 -05:00
Tom Lane 7413caabe6 Avoid leaking memory during large-scale REASSIGN OWNED BY operations.
The various ALTER OWNER routines tend to leak memory in
CurrentMemoryContext.  That's not a problem when they're only called
once per command; but in this usage where we might be touching many
objects, it can amount to a serious memory leak.  Fix that by running
each call in a short-lived context.

(DROP OWNED BY likely has a similar issue, except that you'll probably
run out of lock table space before noticing.  REASSIGN is worth fixing
since for most non-table object types, it won't take any lock.)

Back-patch to all supported branches.  Unfortunately, in the back
branches this helps to only a limited extent, since the sinval message
queue bloats quite a lot in this usage before commit 3aafc030a,
consuming memory more or less comparable to what's actually leaked.
Still, it's clearly a leak with a simple fix, so we might as well fix it.

Justin Pryzby, per report from Guillaume Lelarge

Discussion: https://postgr.es/m/CAECtzeW2DAoioEGBRjR=CzHP6TdL=yosGku8qZxfX9hhtrBB0Q@mail.gmail.com
2021-12-01 13:44:47 -05:00
Alvaro Herrera ef41c3fd6c
Fix determination of broken LSN in OVERWRITTEN_CONTRECORD
In commit ff9f111bce I mixed up inconsistent definitions of the LSN of
the first record in a page, when the previous record ends exactly at the
page boundary.  The correct LSN is adjusted to skip the WAL page header;
I failed to use that when setting XLogReaderState->overwrittenRecPtr,
so at WAL replay time VerifyOverwriteContrecord would refuse to let
replay continue past that record.

Backpatch to 10.  9.6 also contains this bug, but it's no longer being
maintained.

Discussion: https://postgr.es/m/45597.1637694259@sss.pgh.pa.us
2021-11-26 11:14:27 -03:00
Michael Paquier 37827de430 Block ALTER TABLE .. DROP NOT NULL on columns in replica identity index
Replica identities that depend directly on an index rely on a set of
properties, one of them being that all the columns defined in this index
have to be marked as NOT NULL.  There was a hole in the logic with ALTER
TABLE DROP NOT NULL, where it was possible to remove the NOT NULL
property of a column part of an index used as replica identity, so block
it to avoid problems with logical decoding down the road.

The same check was already done columns part of a primary key, so the
fix is straight-forward.

Author: Haiying Tang, Hou Zhijie
Reviewed-by: Dilip Kumar, Michael Paquier
Discussion: https://postgr.es/m/OS0PR01MB6113338C102BEE8B2FFC5BD9FB619@OS0PR01MB6113.jpnprd01.prod.outlook.com
Backpatch-through: 10
2021-11-25 15:05:28 +09:00
Amit Kapila 33b6dd83e2 Fix parallel operations that prevent oldest xmin from advancing.
While determining xid horizons, we skip over backends that are running
Vacuum. We also ignore Create Index Concurrently, or Reindex Concurrently
for the purposes of computing Xmin for Vacuum. But we were not setting the
flags corresponding to these operations when they are performed in
parallel which was preventing Xid horizon from advancing.

The optimization related to skipping Create Index Concurrently, or Reindex
Concurrently operations was implemented in PG-14 but the fix is the same
for the Parallel Vacuum as well so back-patched till PG-13.

Author: Masahiko Sawada
Reviewed-by: Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/CAD21AoCLQqgM1sXh9BrDFq0uzd3RBFKi=Vfo6cjjKODm0Onr5w@mail.gmail.com
2021-11-19 09:24:00 +05:30
Amit Kapila 63c3eeddc2 Invalidate relcache when changing REPLICA IDENTITY index.
When changing REPLICA IDENTITY INDEX to another one, the target table's
relcache was not being invalidated. This leads to skipping update/delete
operations during apply on the subscriber side as the columns required to
search corresponding rows won't get logged.

Author: Tang Haiying, Hou Zhijie
Reviewed-by: Euler Taveira, Amit Kapila
Backpatch-through: 10
Discussion: https://postgr.es/m/OS0PR01MB61133CA11630DAE45BC6AD95FB939@OS0PR01MB6113.jpnprd01.prod.outlook.com
2021-11-16 08:46:12 +05:30
Michael Paquier a691a22983 Fix memory overrun when querying pg_stat_slru
pg_stat_get_slru() in pgstatfuncs.c would point to one element after the
end of the array PgStat_SLRUStats when finishing to scan its entries.
This had no direct consequences as no data from the extra memory area
was read, but static analyzers would rightfully complain here.  So let's
be clean.

While on it, this adds one regression test in the area reserved for
system views.

Reported-by: Alexander Kozhemyakin, via AddressSanitizer
Author: Kyotaro Horiguchi
Discussion: https://postgr.es/m/17280-37da556e86032070@postgresql.org
Backpatch-through: 13
2021-11-12 21:50:08 +09:00
Noah Misch d4e9d69469 Report any XLogReadRecord() error in XlogReadTwoPhaseData().
Buildfarm members kittiwake and tadarida have witnessed errors at this
site.  The site discarded key facts.  Back-patch to v10 (all supported
versions).

Reviewed by Michael Paquier and Tom Lane.

Discussion: https://postgr.es/m/20211107013157.GB790288@rfd.leadboat.com
2021-11-11 17:11:01 -08:00
Tom Lane 78f058411b Doc: improve protocol spec for logical replication Type messages.
protocol.sgml documented the layout for Type messages, but completely
dropped the ball otherwise, failing to explain what they are, when
they are sent, or what they're good for.  While at it, do a little
copy-editing on the description of Relation messages.

In passing, adjust the comment for apply_handle_type() to make it
clearer that we choose not to do anything when receiving a Type
message, not that we think it has no use whatsoever.

Per question from Stefen Hillman.

Discussion: https://postgr.es/m/CAPgW8pMknK5pup6=T4a_UG=Cz80Rgp=KONqJmTdHfaZb0RvnFg@mail.gmail.com
2021-11-10 13:12:58 -05:00
Tom Lane e92ed93e8e Reject extraneous data after SSL or GSS encryption handshake.
The server collects up to a bufferload of data whenever it reads data
from the client socket.  When SSL or GSS encryption is requested
during startup, any additional data received with the initial
request message remained in the buffer, and would be treated as
already-decrypted data once the encryption handshake completed.
Thus, a man-in-the-middle with the ability to inject data into the
TCP connection could stuff some cleartext data into the start of
a supposedly encryption-protected database session.

This could be abused to send faked SQL commands to the server,
although that would only work if the server did not demand any
authentication data.  (However, a server relying on SSL certificate
authentication might well not do so.)

To fix, throw a protocol-violation error if the internal buffer
is not empty after the encryption handshake.

Our thanks to Jacob Champion for reporting this problem.

Security: CVE-2021-23214
2021-11-08 11:01:43 -05:00
Alvaro Herrera 7c0a78f089
Fix typo
Introduced in 1d97d3d086.

Co-authored-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/83641f59-d566-b33e-ef21-a272a98675aa@gmail.com
2021-11-08 09:17:24 -03:00
Peter Eisentraut 98da5cd0d1 Translation updates
Source-Git-URL: git://git.postgresql.org/git/pgtranslation/messages.git
Source-Git-Hash: 027ff7dad8afb1a907cb4c59da4e13c3ace8d376
2021-11-08 10:08:56 +01:00
Alexander Korotkov e1fee28a04 Reset lastOverflowedXid on standby when needed
Currently, lastOverflowedXid is never reset.  It's just adjusted on new
transactions known to be overflowed.  But if there are no overflowed
transactions for a long time, snapshots could be mistakenly marked as
suboverflowed due to wraparound.

This commit fixes this issue by resetting lastOverflowedXid when needed
altogether with KnownAssignedXids.

Backpatch to all supported versions.

Reported-by: Stan Hu
Discussion: https://postgr.es/m/CAMBWrQ%3DFp5UAsU_nATY7EMY7NHczG4-DTDU%3DmCvBQZAQ6wa2xQ%40mail.gmail.com
Author: Kyotaro Horiguchi, Alexander Korotkov
Reviewed-by: Stan Hu, Simon Riggs, Nikolay Samokhvalov, Andrey Borodin, Dmitry Dolgov
2021-11-06 18:34:19 +03:00
Alvaro Herrera bf5cdcfd5e
Avoid crash in rare case of concurrent DROP
When a role being dropped contains is referenced by catalog objects that
are concurrently also being dropped, a crash can result while trying to
construct the string that describes the objects.  Suppress that by
ignoring objects whose descriptions are returned as NULL.

The majority of relevant codesites were already cautious about this
already; we had just missed a couple.

This is an old bug, so backpatch all the way back.

Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/17126-21887f04508cb5c8@postgresql.org
2021-11-05 12:29:34 -03:00
Heikki Linnakangas 07070c0082 Fix snapshot reference leak if lo_export fails.
If lo_export() fails to open the target file or to write to it, it leaks
the created LargeObjectDesc and its snapshot in the top-transaction
context and resource owner. That's pretty harmless, it's a small leak
after all, but it gives the user a "Snapshot reference leak" warning.

Fix by using a short-lived memory context and no resource owner for
transient LargeObjectDescs that are opened and closed within one function
call. The leak is easiest to reproduce with lo_export() on a directory
that doesn't exist, but in principle the other lo_* functions could also
fail.

Backpatch to all supported versions.

Reported-by: Andrew B
Reviewed-by: Alvaro Herrera
Discussion: https://www.postgresql.org/message-id/32bf767a-2d65-71c4-f170-122f416bab7e@iki.fi
2021-11-03 10:54:36 +02:00
Tom Lane ada667b454 Fix variable lifespan in ExecInitCoerceToDomain().
This undoes a mistake in 1ec7679f1: domainval and domainnull were
meant to live across loop iterations, but they were incorrectly
moved inside the loop.  The effect was only to emit useless extra
EEOP_MAKE_READONLY steps, so it's not a big deal; nonetheless,
back-patch to v13 where the mistake was introduced.

Ranier Vilela

Discussion: https://postgr.es/m/CAEudQAqXuhbkaAp-sGH6dR6Nsq7v28_0TPexHOm6FiDYqwQD-w@mail.gmail.com
2021-11-02 13:36:57 -04:00
Tom Lane 0151af40cd Avoid O(N^2) behavior in SyncPostCheckpoint().
As in commits 6301c3ada and e9d9ba2a4, avoid doing repetitive
list_delete_first() operations, since that would be expensive when
there are many files waiting to be unlinked.  This is a slightly
larger change than in those cases.  We have to keep the list state
valid for calls to AbsorbSyncRequests(), so it's necessary to invent a
"canceled" field instead of immediately deleting PendingUnlinkEntry
entries.  Also, because we might not be able to process all the
entries, we need a new list primitive list_delete_first_n().

list_delete_first_n() is almost list_copy_tail(), but it modifies the
input List instead of making a new copy.  I found a couple of existing
uses of the latter that could profitably use the new function.  (There
might be more, but the other callers look like they probably shouldn't
overwrite the input List.)

As before, back-patch to v13.

Discussion: https://postgr.es/m/CD2F0E7F-9822-45EC-A411-AE56F14DEA9F@amazon.com
2021-11-02 11:31:54 -04:00
Tom Lane e477642a1b Avoid some other O(N^2) hazards in list manipulation.
In the same spirit as 6301c3ada, fix some more places where we were
using list_delete_first() in a loop and thereby risking O(N^2)
behavior.  It's not clear that the lists manipulated in these spots
can get long enough to be really problematic ... but it's not clear
that they can't, either, and the fixes are simple enough.

As before, back-patch to v13.

Discussion: https://postgr.es/m/CD2F0E7F-9822-45EC-A411-AE56F14DEA9F@amazon.com
2021-11-01 16:24:40 -04:00
Alvaro Herrera 17227825ca
Handle XLOG_OVERWRITE_CONTRECORD in DecodeXLogOp
Failing to do so results in inability of logical decoding to process the
WAL stream.  Handle it by doing nothing.

Backpatch all the way back.

Reported-by: Petr Jelínek <petr.jelinek@enterprisedb.com>
2021-11-01 13:07:23 -03:00
Michael Paquier 77f7909a40 Preserve opclass parameters across REINDEX CONCURRENTLY
The opclass parameter Datums from the old index are fetched in the same
way as for predicates and expressions, by grabbing them directly from
the system catalogs.  They are then copied into the new IndexInfo that
will be used for the creation of the new copy.

This caused the new index to be rebuilt with default parameters rather
than the ones pre-defined by a user.  The only way to get back a new
index with correct opclass parameters would be to recreate a new index
from scratch.

The issue has been introduced by 911e702.

Author: Michael Paquier
Reviewed-by: Zhihong Yu
Discussion: https://postgr.es/m/YX0CG/QpLXcPr8HJ@paquier.xyz
Backpatch-through: 13
2021-11-01 11:40:29 +09:00
Tom Lane df238aed10 Avoid O(N^2) behavior when the standby process releases many locks.
When replaying a transaction that held many exclusive locks on the
primary, a standby server's startup process would expend O(N^2)
effort on manipulating the list of locks.  This code was fine when
written, but commit 1cff1b95a made repetitive list_delete_first()
calls inefficient, as explained in its commit message.  Fix by just
iterating the list normally, and releasing storage only when done.
(This'd be inadequate if we needed to recover from an error occurring
partway through; but we don't.)

Back-patch to v13 where 1cff1b95a came in.

Nathan Bossart

Discussion: https://postgr.es/m/CD2F0E7F-9822-45EC-A411-AE56F14DEA9F@amazon.com
2021-10-31 15:31:44 -04:00
Peter Geoghegan d5a2ffbce5 Fix ordering of items in nbtree error message.
Oversight in commit a5213adf.

Backpatch: 13-, just like commit a5213adf.
2021-10-27 13:09:00 -07:00
Peter Geoghegan f8cce4a3d8 Further harden nbtree posting split code.
Add more defensive checks around posting list split code.  These should
detect corruption involving duplicate table TIDs earlier and more
reliably than any existing check.

Follow up to commit 8f72bbac.

Discussion: https://postgr.es/m/CAH2-WzkrSY_kjyd1_M5xJK1uM0govJXMxPn8JUSvwcUOiHuWVw@mail.gmail.com
Backpatch: 13-, where nbtree deduplication was introduced.
2021-10-27 12:10:43 -07:00
Thomas Munro 24b7cf8a5c Reject huge_pages=on if shared_memory_type=sysv.
It doesn't work (it could, but hasn't been implemented).
Back-patch to 12, where shared_memory_type arrived.

Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/163271880203.22789.1125998876173795966@wrigleys.postgresql.org
2021-10-26 13:04:40 +13:00
Noah Misch a9d0a54094 Fix CREATE INDEX CONCURRENTLY for the newest prepared transactions.
The purpose of commit 8a54e12a38 was to
fix this, and it sufficed when the PREPARE TRANSACTION completed before
the CIC looked for lock conflicts.  Otherwise, things still broke.  As
before, in a cluster having used CIC while having enabled prepared
transactions, queries that use the resulting index can silently fail to
find rows.  It may be necessary to reindex to recover from past
occurrences; REINDEX CONCURRENTLY suffices.  Fix this for future index
builds by making CIC wait for arbitrarily-recent prepared transactions
and for ordinary transactions that may yet PREPARE TRANSACTION.  As part
of that, have PREPARE TRANSACTION transfer locks to its dummy PGPROC
before it calls ProcArrayClearTransaction().  Back-patch to 9.6 (all
supported versions).

Andrey Borodin, reviewed (in earlier versions) by Andres Freund.

Discussion: https://postgr.es/m/01824242-AA92-4FE9-9BA7-AEBAFFEA3D0C@yandex-team.ru
2021-10-23 18:36:42 -07:00
Noah Misch 2e33b43599 Avoid race in RelationBuildDesc() affecting CREATE INDEX CONCURRENTLY.
CIC and REINDEX CONCURRENTLY assume backends see their catalog changes
no later than each backend's next transaction start.  That failed to
hold when a backend absorbed a relevant invalidation in the middle of
running RelationBuildDesc() on the CIC index.  Queries that use the
resulting index can silently fail to find rows.  Fix this for future
index builds by making RelationBuildDesc() loop until it finishes
without accepting a relevant invalidation.  It may be necessary to
reindex to recover from past occurrences; REINDEX CONCURRENTLY suffices.
Back-patch to 9.6 (all supported versions).

Noah Misch and Andrey Borodin, reviewed (in earlier versions) by Andres
Freund.

Discussion: https://postgr.es/m/20210730022548.GA1940096@gust.leadboat.com
2021-10-23 18:36:42 -07:00
Amit Kapila 23469b867a Back-patch "Add parent table name in an error in reorderbuffer.c."
This was originally done in commit 5e77625b26 for 15 only, as a
troubleshooting aid but multiple people showed interest in back-patching
this.

Author: Jeremy Schneider
Reviewed-by: Amit Kapila
Backpatch-through: 9.6
Discussion: https://postgr.es/m/808ed65b-994c-915a-361c-577f088b837f@amazon.com
2021-10-21 09:36:27 +05:30
Alvaro Herrera 842fe6123c
Ensure correct lock level is used in ALTER ... RENAME
Commit 1b5d797cd4 intended to relax the lock level used to rename
indexes, but inadvertently allowed *any* relation to be renamed with a
lowered lock level, as long as the command is spelled ALTER INDEX.
That's undesirable for other relation types, so retry the operation with
the higher lock if the relation turns out not to be an index.

After this fix, ALTER INDEX <sometable> RENAME will require access
exclusive lock, which it didn't before.

Author: Nathan Bossart <bossartn@amazon.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Onder Kalaci <onderk@microsoft.com>
Discussion: https://postgr.es/m/PH0PR21MB1328189E2821CDEC646F8178D8AE9@PH0PR21MB1328.namprd21.prod.outlook.com
2021-10-19 19:08:45 -03:00
Tom Lane 30e61a8cdc Fix assignment to array of domain over composite.
An update such as "UPDATE ... SET fld[n].subfld = whatever"
failed if the array elements were domains rather than plain
composites.  That's because isAssignmentIndirectionExpr()
failed to cope with the CoerceToDomain node that would appear
in the expression tree in this case.  The result would typically
be a crash, and even if we accidentally didn't crash, we'd not
correctly preserve other fields of the same array element.

Per report from Onder Kalaci.  Back-patch to v11 where arrays of
domains came in.

Discussion: https://postgr.es/m/PH0PR21MB132823A46AA36F0685B7A29AD8BD9@PH0PR21MB1328.namprd21.prod.outlook.com
2021-10-19 13:54:46 -04:00
Tom Lane cf33fb7f4a Remove bogus assertion in transformExpressionList().
I think when I added this assertion (in commit 8f889b108), I was only
thinking of the use of transformExpressionList at top level of INSERT
and VALUES.  But it's also called by transformRowExpr(), which can
certainly occur in an UPDATE targetlist, so it's inappropriate to
suppose that p_multiassign_exprs must be empty.  Besides, since the
input is not expected to contain ResTargets, there's no reason it
should contain MultiAssignRefs either.  Hence this code need not
be concerned about the state of p_multiassign_exprs, and we should
just drop the assertion.

Per bug #17236 from ocean_li_996.  It's been wrong for years,
so back-patch to all supported branches.

Discussion: https://postgr.es/m/17236-3210de9bcba1d7ca@postgresql.org
2021-10-19 11:35:15 -04:00
Michael Paquier 85dc4292a7 Block ALTER INDEX/TABLE index_name ALTER COLUMN colname SET (options)
The grammar of this command run on indexes with column names has always
been authorized by the parser, and it has never been documented.

Since 911e702, it is possible to define opclass parameters as of CREATE
INDEX, which actually broke the old case of ALTER INDEX/TABLE where
relation-level parameters n_distinct and n_distinct_inherited could be
defined for an index (see 76a47c0 and its thread where this point has
been touched, still remained unused).  Attempting to do that in v13~
would cause the index to become unusable, as there is a new dedicated
code path to load opclass parameters instead of the relation-level ones
previously available.  Note that it is possible to fix things with a
manual catalog update to bring the relation back online.

This commit disables this command for now as the use of column names for
indexes does not make sense anyway, particularly when it comes to index
expressions where names are automatically computed.  One way to properly
support this case properly in the future would be to use column numbers
when it comes to indexes, in the same way as ALTER INDEX .. ALTER COLUMN
.. SET STATISTICS.

Partitioned indexes were already blocked, but not indexes.  Some tests
are added for both cases.

There was some code in ANALYZE to enforce n_distinct to be used for an
index expression if the parameter was defined, but just remove it for
now until/if there is support for this (note that index-level parameters
never had support in pg_dump either, previously), so this was just dead
code.

Reported-by: Matthijs van der Vleuten
Author: Nathan Bossart, Michael Paquier
Reviewed-by: Vik Fearing, Dilip Kumar
Discussion: https://postgr.es/m/17220-15d684c6c2171a83@postgresql.org
Backpatch-through: 13
2021-10-19 11:04:04 +09:00
Alvaro Herrera fe35528a5e
Invalidate partitions of table being attached/detached
Failing to do that, any direct inserts/updates of those partitions
would fail to enforce the correct constraint, that is, one that
considers the new partition constraint of their parent table.

Backpatch to 10.

Reported by: Hou Zhijie <houzj.fnst@fujitsu.com>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Nitin Jadhav <nitinjadhavpostgres@gmail.com>
Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>

Discussion: https://postgr.es/m/OS3PR01MB5718DA1C4609A25186D1FBF194089%40OS3PR01MB5718.jpnprd01.prod.outlook.com
2021-10-18 19:08:25 -03:00
Michael Paquier 8f4fe8d7f8 Reset properly snapshot export state during transaction abort
During a replication slot creation, an ERROR generated in the same
transaction as the one creating a to-be-exported snapshot would have
left the backend in an inconsistent state, as the associated static
export snapshot state was not being reset on transaction abort, but only
on the follow-up command received by the WAL sender that created this
snapshot on replication slot creation.  This would trigger inconsistency
failures if this session tried to export again a snapshot, like during
the creation of a replication slot.

Note that a snapshot export cannot happen in a transaction block, so
there is no need to worry resetting this state for subtransaction
aborts.  Also, this inconsistent state would very unlikely show up to
users.  For example, one case where this could happen is an
out-of-memory error when building the initial snapshot to-be-exported.
Dilip found this problem while poking at a different patch, that caused
an error in this code path for reasons unrelated to HEAD.

Author: Dilip Kumar
Reviewed-by: Michael Paquier, Zhihong Yu
Discussion: https://postgr.es/m/CAFiTN-s0zA1Kj0ozGHwkYkHwa5U0zUE94RSc_g81WrpcETB5=w@mail.gmail.com
Backpatch-through: 9.6
2021-10-18 11:56:52 +09:00
Jeff Davis 20f785732f Check criticalSharedRelcachesBuilt in GetSharedSecurityLabel().
An extension may want to call GetSecurityLabel() on a shared object
before the shared relcaches are fully initialized. For instance, a
ClientAuthentication_hook might want to retrieve the security label on
a role.

Discussion: https://postgr.es/m/ecb7af0b26e3be1d96d291c8453a86f1f82d9061.camel@j-davis.com
Backpatch-through: 9.6
2021-10-14 12:24:47 -07:00
Tom Lane fdd6a4d8d9 Fix planner error with pulling up subquery expressions into function RTEs.
If a function-in-FROM laterally references the output of some sub-SELECT
earlier in the FROM clause, and we are able to flatten that sub-SELECT
into the outer query, the expression(s) copied into the function RTE
missed being processed by eval_const_expressions.  This'd lead to trouble
and probable crashes at execution if such expressions contained
named-argument function call syntax or functions with defaulted arguments.
The bug is masked if the query contains any explicit JOIN syntax, which
may help explain why we'd not noticed.

Per bug #17227 from Bernd Dorn.  This is an oversight in commit 7266d0997,
so back-patch to v13 where that came in.

Discussion: https://postgr.es/m/17227-5a28ed1512189fa4@postgresql.org
2021-10-14 12:43:43 -04:00
Etsuro Fujita 08f37e2592 Add missing word to comment in joinrels.c.
Author: Amit Langote
Backpatch-through: 13
Discussion: https://postgr.es/m/CA%2BHiwqGQNbtamQ_9DU3osR1XiWR4wxWFZurPmN6zgbdSZDeWmw%40mail.gmail.com
2021-10-07 17:45:03 +09:00