If CheckAttributeType() threw an error about the datatype of an
index expression column, it would report an empty column name,
which is pretty unhelpful and certainly not the intended behavior.
I (tgl) evidently broke this in commit cfc5008a5, by not noticing
that the column's attname was used above where I'd placed the
assignment of it.
In HEAD and v12, this is trivially fixable by moving up the
assignment of attname. Before v12 the code is a bit more messy;
to avoid doing substantial refactoring, I took the lazy way out
and just put in two copies of the assignment code.
Report and patch by Amit Langote. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/CA+HiwqFA+BGyBFimjiYXXMa2Hc3fcL0+OJOyzUNjhU4NCa_XXw@mail.gmail.com
This Assert thought that an overflowed transaction can never get registered
for the group update. But that is not true, because even when the number
of children for a transaction got reduced, the overflow flag is not
changed. And, for group update, we only care about the current number of
children for a transaction that is being committed.
Based on comments by Andres Freund, remove a redundant Assert in
TransactionIdSetPageStatus as we already had a static Assert for the same
condition a few lines earlier.
Reported-by: Vignesh C
Author: Dilip Kumar
Reviewed-by: Amit Kapila
Backpatch-through: 11
Discussion: https://postgr.es/m/CAFiTN-s5=uJw-Z6JC9gcqtBSjXsrHnU63PXBrA=pnBjqnkm5UA@mail.gmail.com
The DTK_DOW/DTK_ISODOW and DTK_DOY switch cases in timestamp_part() and
timestamptz_part() contained calls of timestamp2tm() that were fully
redundant with the ones done just above the switch. This evidently crept
in during commit 258ee1b63, which relocated that code from another place
where the calls were indeed needed. Just delete the redundant calls.
I (tgl) noted that our test coverage of these functions left quite a
bit to be desired, so extend timestamp.sql and timestamptz.sql to
cover all the branches.
Back-patch to all supported branches, as the previous commit was.
There's no real issue here other than some wasted cycles in some
not-too-heavily-used code paths, but the test coverage seems valuable.
Report and patch by Li Japin; test case adjustments by me.
Discussion: https://postgr.es/m/SG2PR06MB37762CAE45DB0F6CA7001EA9B6550@SG2PR06MB3776.apcprd06.prod.outlook.com
pg_signal_dispatch_thread() responded to the client (signal sender)
and disconnected the pipe before actually setting the shared variables
that make the signal visible to the backend process's main thread.
In the worst case, it seems, effective delivery of the signal could be
postponed for as long as the machine has any other work to do.
To fix, just move the pg_queue_signal() call so that we do it before
responding to the client. This essentially makes pgkill() synchronous,
which is a stronger guarantee than we have on Unix. That may be
overkill, but on the other hand we have not seen comparable timing bugs
on any Unix platform.
While at it, add some comments to this sadly underdocumented code.
Problem diagnosis and fix by Amit Kapila; I just added the comments.
Back-patch to all supported versions, as it appears that this can cause
visible NOTIFY timing oddities on all of them, and there might be
other misbehavior due to slow delivery of other signals.
Discussion: https://postgr.es/m/32745.1575303812@sss.pgh.pa.us
We implement ON COMMIT DELETE ROWS by truncating tables marked that
way, which requires also truncating/rebuilding their indexes. But
RelationTruncateIndexes asks the relcache for up-to-date copies of any
index expressions, which may cause execution of eval_const_expressions
on them, which can result in actual execution of subexpressions.
This is a bad thing to have happening during ON COMMIT. Manuel Rigger
reported that use of a SQL function resulted in crashes due to
expectations that ActiveSnapshot would be set, which it isn't.
The most obvious fix perhaps would be to push a snapshot during
PreCommit_on_commit_actions, but I think that would just open the door
to more problems: CommitTransaction explicitly expects that no
user-defined code can be running at this point.
Fortunately, since we know that no tuples exist to be indexed, there
seems no need to use the real index expressions or predicates during
RelationTruncateIndexes. We can set up dummy index expressions
instead (we do need something that will expose the right data type,
as there are places that build index tupdescs based on this), and
just ignore predicates and exclusion constraints.
In a green field it'd likely be better to reimplement ON COMMIT DELETE
ROWS using the same "init fork" infrastructure used for unlogged
relations. That seems impractical without catalog changes though,
and even without that it'd be too big a change to back-patch.
So for now do it like this.
Per private report from Manuel Rigger. This has been broken forever,
so back-patch to all supported branches.
The fix for CVE-2017-7484 disallowed use of pg_statistic data for
planning purposes if the user would not be able to select the associated
column and a non-leakproof function is to be applied to the statistics
values. That turns out to disable use of pg_statistic data in some
common cases involving inheritance/partitioning, where the user does
have permission to select from the parent table that was actually named
in the query, but not from a child table whose stats are needed. Since,
in non-corner cases, the user *can* select the child table's data via
the parent, this restriction is not actually useful from a security
standpoint. Improve the logic so that we also check the permissions of
the originally-named table, and allow access if select permission exists
for that.
When checking access to stats for a simple child column, we can map
the child column number back to the parent, and perform this test
exactly (including not allowing access if the child column isn't
exposed by the parent). For expression indexes, the current logic
just insists on whole-table select access, and this patch allows
access if the user can select the whole parent table. In principle,
if the child table has extra columns, this might allow access to
stats on columns the user can't read. In practice, it's unlikely
that the planner is going to do any stats calculations involving
expressions that are not visible to the query, so we'll ignore that
fine point for now. Perhaps someday we'll improve that logic to
detect exactly which columns are used by an expression index ...
but today is not that day.
Back-patch to v11. The issue was created in 9.2 and up by the
CVE-2017-7484 fix, but this patch depends on the append_rel_array[]
planner data structure which only exists in v11 and up. In
practice the issue is most urgent with partitioned tables, so
fixing v11 and later should satisfy much of the practical need.
Dilip Kumar and Amit Langote, with some kibitzing by me
Discussion: https://postgr.es/m/3876.1531261875@sss.pgh.pa.us
Revert part of commit 19df1702f5.
Early shutdown was added by that commit so that we could collect
statistics from workers, but unfortunately, it interacted badly with
rescans. The problem is that we ended up destroying the parallel context
which is required for rescans. This leads to rescans of a Limit node over
a Gather node to produce unpredictable results as it tries to access
destroyed parallel context. By reverting the early shutdown code, we
might lose statistics in some cases of Limit over Gather [Merge], but that
will require further study to fix.
Reported-by: Jerry Sievers
Diagnosed-by: Thomas Munro
Author: Amit Kapila, testcase by Vignesh C
Backpatch-through: 9.6
Discussion: https://postgr.es/m/87ims2amh6.fsf@jsievers.enova.com
If LISTEN is the only action in a serializable-mode transaction,
and the session was not previously listening, and the notify queue
is not empty, predicate.c reported an assertion failure. That
happened because we'd acquire the transaction's initial snapshot
during PreCommit_Notify, which was called *after* predicate.c
expects any such snapshot to have been established.
To fix, just swap the order of the PreCommit_Notify and
PreCommit_CheckForSerializationFailure calls during CommitTransaction.
This will imply holding the notify-insertion lock slightly longer,
but the difference could only be meaningful in serializable mode,
which is an expensive option anyway.
It appears that this is just an assertion failure, with no
consequences in non-assert builds. A snapshot used only to scan
the notify queue could not have been involved in any serialization
conflicts, so there would be nothing for
PreCommit_CheckForSerializationFailure to do except assign it a
prepareSeqNo and set the SXACT_FLAG_PREPARED flag. And given no
conflicts, neither of those omissions affect the behavior of
ReleasePredicateLocks. This admittedly once-over-lightly analysis
is backed up by the lack of field reports of trouble.
Per report from Mark Dilger. The bug is old, so back-patch to all
supported branches; but the new test case only goes back to 9.6,
for lack of adequate isolationtester infrastructure before that.
Discussion: https://postgr.es/m/3ac7f397-4d5f-be8e-f354-440020675694@gmail.com
Discussion: https://postgr.es/m/13881.1574557302@sss.pgh.pa.us
This patch ensures that, if any notify messages were received during
a just-finished transaction, they get sent to the frontend just before
not just after the ReadyForQuery message. With libpq and other client
libraries that act similarly, this guarantees that the client will see
the notify messages as available as soon as it thinks the transaction
is done.
This probably makes no difference in practice, since in realistic
use-cases the application would have to cope with asynchronous
arrival of notify events anyhow. However, it makes it a lot easier
to build cross-session-notify test cases with stable behavior.
I'm a bit surprised now that we've not seen any buildfarm instability
with the test cases added by commit b10f40bf0. Tests that I intend
to add in an upcoming bug fix are definitely unstable without this.
Back-patch to 9.6, which is as far back as we can do NOTIFY testing
with the isolationtester infrastructure.
Discussion: https://postgr.es/m/13881.1574557302@sss.pgh.pa.us
slot_modify_cstrings seriously abused the TupleTableSlot API by relying
on a slot's underlying data to stay valid across ExecClearTuple. Since
this abuse was also quite undocumented, it's little surprise that the
case got broken during the v12 slot rewrites. As reported in bug #16129
from Ondřej Jirman, this could lead to crashes or data corruption when
a logical replication subscriber processes a row update. Problems would
only arise if the subscriber's table contained columns of pass-by-ref
types that were not being copied from the publisher.
Fix by explicitly copying the datum/isnull arrays from the source slot
that the old row was in already. This ends up being about the same
thing that happened pre-v12, but hopefully in a less opaque and
fragile way.
We might've caught the problem sooner if there were any test cases
dealing with updates involving non-replicated or dropped columns.
Now there are.
Back-patch to v10 where this code came in. Even though the failure
does not manifest before v12, IMO this code is too fragile to leave
as-is. In any case we certainly want the additional test coverage.
Patch by me; thanks to Tomas Vondra for initial investigation.
Discussion: https://postgr.es/m/16129-a0c0f48e71741e5f@postgresql.org
While a self-referential view doesn't actually work, it's possible
to create one, and it turns out that this breaks some of the
information_schema views. Those views call relation_is_updatable(),
which neglected to consider the hazards of being recursive. In
older PG versions you get a "stack depth limit exceeded" error,
but since v10 it'd recurse to the point of stack overrun and crash,
because commit a4c35ea1c took out the expression_returns_set() call
that was incidentally checking the stack depth.
Since this function is only used by information_schema views, it
seems like it'd be better to return "not updatable" than suffer
an error. Hence, add tracking of what views we're examining,
in just the same way that the nearby fireRIRrules() code detects
self-referential views. I added a check_stack_depth() call too,
just to be defensive.
Per private report from Manuel Rigger. Back-patch to all
supported versions.
Trying to use hypothetical indexes with BRIN currently fails when trying
to access a relation that does not exist when looking for the
statistics. With the current API, it is not possible to easily pass
a value for pages_per_range down to the hypothetical index, so this
makes use of the default value of BRIN_DEFAULT_PAGES_PER_RANGE, which
should be fine enough in most cases.
Being able to refine or enforce the hypothetical costs in more
optimistic ways would require more refactoring by filling in the
statistics when building IndexOptInfo in plancat.c. This would involve
ABI breakages around the costing routines, something not fit for stable
branches.
This is broken since 7e534ad, so backpatch down to v10.
Author: Julien Rouhaud, Heikki Linnakangas
Reviewed-by: Álvaro Herrera, Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/CAOBaU_ZH0LKEA8VFCocr6Lpte1ab0b6FpvgS0y4way+RPSXfYg@mail.gmail.com
Backpatch-through: 10
By oversight 52ac6cd2d0 makes ginDeletePage() sets pd_prune_xid of page to be
deleted before entering the critical section. It appears that only versions 11
and later were affected by this oversight.
Backpatch-through: 11
We find GIN concurrency bugs from time to time. One of the problems here is
that concurrency of GIN isn't well-documented in README. So, it might be even
hard to distinguish design bugs from implementation bugs.
This commit revised concurrency section in GIN README providing more details.
Some examples are illustrated in ASCII art.
Also, this commit add the explanation of how is tuple layout in internal GIN
B-tree page different in comparison with nbtree.
Discussion: https://postgr.es/m/CAPpHfduXR_ywyaVN4%2BOYEGaw%3DcPLzWX6RxYLBncKw8de9vOkqw%40mail.gmail.com
Author: Alexander Korotkov
Reviewed-by: Peter Geoghegan
Backpatch-through: 9.4
Current GIN code appears to don't handle traversing to the deleted page via
downlink. This commit fixes that by stepping right from the delete page like
we do in nbtree.
This commit also fixes setting 'deleted' flag to the GIN pages. Now other page
flags are not erased once page is deleted. That helps to keep our assertions
true if we arrive deleted page via downlink.
Discussion: https://postgr.es/m/CAPpHfdvMvsw-NcE5bRS7R1BbvA4BxoDnVVjkXC5W0Czvy9LVrg%40mail.gmail.com
Author: Alexander Korotkov
Reviewed-by: Peter Geoghegan
Backpatch-through: 9.4
When ginDeletePage() is about to delete page it locks its left sibling to revise
the rightlink. So, it locks pages in right to left manner. Int he same time
ginStepRight() locks pages in left to right manner, and that could cause a
deadlock.
This commit makes ginScanToDelete() keep exclusive lock on left siblings of
currently investigated path. That elimites need to relock left sibling in
ginDeletePage(). Thus, deadlock with ginStepRight() can't happen anymore.
Reported-by: Chen Huajun
Discussion: https://postgr.es/m/5c332bd1.87b6.16d7c17aa98.Coremail.chjischj%40163.com
Author: Alexander Korotkov
Reviewed-by: Peter Geoghegan
Backpatch-through: 10
It turns out that commit e9f1c01b7 missed a case: we must print a
VALUES clause in long format if get_query_def is given a resultDesc
that would require the query's output column name(s) to be different
from what the bare VALUES clause would produce.
This applies in case an ALTER ... RENAME COLUMN has been done to
a view that formerly could be printed in simple format, as shown
in the added regression test case. It also explains bug #16119
from Dmitry Telpt, because it turns out that (unlike CREATE VIEW)
CREATE MATERIALIZED VIEW fails to apply any column aliases it's
given to the stored ON SELECT rule. So to get them to be printed,
we have to account for the resultDesc renaming. It might be worth
changing the matview code so that it creates the ON SELECT rule
with the correct aliases; but we'd still need these messy checks in
get_simple_values_rte to handle the case of a subsequent column
rename, so any such change would be just neatnik-ism not a bug fix.
Like the previous patch, back-patch to all supported branches.
Discussion: https://postgr.es/m/16119-e64823f30a45a754@postgresql.org
When estimating number of distinct groups, we failed to ignore system
attributes when matching the group expressions to mvdistinct stats,
causing failures like
ERROR: negative bitmapset member not allowed
Fix that by simply skipping anything that is not a regular attribute.
Backpatch to PostgreSQL 10, where the extended stats were introduced.
Bug: #16111
Reported-by: Tuomas Leikola
Author: Tomas Vondra
Backpatch-through: 10
Discussion: https://postgr.es/m/16111-687799584c3a7e73@postgresql.org
Call ExecShutdownNode() after ExecutePlan()'s loop, rather than at each
break. We had forgotten to do that in one case. The omission caused
intermittent "temporary file leak" warnings from multi-batch parallel
hash joins with a LIMIT clause.
Back-patch to 11. Though the problem exists in theory in earlier
parallel query releases, nothing really depended on it.
Author: Kyotaro Horiguchi
Reviewed-by: Thomas Munro, Amit Kapila
Discussion: https://postgr.es/m/20191111.212418.2222262873417235945.horikyota.ntt%40gmail.com
Commit 6b76f1bb5 changed all the RADIUS auth parameters to be lists
rather than single values. But its use of SplitIdentifierString
to parse the list format was not very carefully thought through,
because that function thinks it's parsing SQL identifiers, which
means it will (a) downcase the strings and (b) truncate them to
be shorter than NAMEDATALEN. While downcasing should be harmless
for the server names and ports, it's just wrong for the shared
secrets, and probably for the NAS Identifier strings as well.
The truncation aspect is at least potentially a problem too,
though typical values for these parameters would fit in 63 bytes.
Fortunately, we now have a function SplitGUCList that is exactly
the same except for not doing the two unwanted things, so fixing
this is a trivial matter of calling that function instead.
While here, improve the documentation to show how to double-quote
the parameter values. I failed to resist the temptation to do
some copy-editing as well.
Report and patch from Marcos David (bug #16106); doc changes by me.
Back-patch to v10 where the aforesaid commit came in, since this is
arguably a regression from our previous behavior with RADIUS auth.
Discussion: https://postgr.es/m/16106-7d319e4295d08e70@postgresql.org
The TableFunc node (i.e., XMLTABLE) includes type and collation OIDs
that might not be referenced anywhere else in the expression tree,
so they need to be accounted for when extracting dependencies.
Fortunately, the practical effects of this are limited, since
(a) it's somewhat unlikely that people would be extracting
columns of non-builtin types from an XML document, and (b)
in many scenarios, the query would contain other references
to such types, or functions depending on them. However, it's
not hard to construct examples wherein the existing code lets
one drop a type used in XMLTABLE and thereby break a view.
This is evidently an original oversight in the XMLTABLE patch,
so back-patch to v10 where that came in.
Discussion: https://postgr.es/m/18427.1573508501@sss.pgh.pa.us
This happens when we add a replica identity column on a subscriber
that does not yet exist on the publisher, according to the mapping
maintained by the subscriber. Code that checks whether the target
relation on the subscriber is updatable would check the replica
identity attribute bitmap with a column number -1, which would result
in an error. To fix, skip such columns in the bitmap lookup and
consider the relation not updatable. The result is consistent with
the rule that the replica identity columns on the subscriber must be a
subset of those on the publisher, since if the column doesn't exist on
the publisher, the column set on the subscriber can't be a subset.
Reported-by: Tim Clarke <tim.clarke@minerva.info>
Analyzed-by: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Discussion: https://www.postgresql.org/message-id/flat/a9139c29-7ddd-973b-aa7f-71fed9c38d75%40minerva.info
SET CONSTRAINTS ... DEFERRED failed on partitioned tables, because of a
sanity check that ensures that the affected constraints have triggers.
On partitioned tables, the triggers are in the leaf partitions, not in
the partitioned relations themselves, so the sanity check fails.
Removing the sanity check solves the problem, because the code needed to
support the case is already there.
Backpatch to 11.
Note: deferred unique constraints are not affected by this bug, because
they do have triggers in the parent partitioned table. I did not add a
test for this scenario.
Discussion: https://postgr.es/m/20191105212915.GA11324@alvherre.pgsql
This patch adopts the overflow check logic introduced by commit cbdb8b4c0
into two more places. interval_mul() failed to notice if it computed a
new microseconds value that was one more than INT64_MAX, and pgbench's
double-to-int64 logic had the same sorts of edge-case problems that
cbdb8b4c0 fixed in the core code.
To make this easier to get right in future, put the guts of the checks
into new macros in c.h, and add commentary about how to use the macros
correctly.
Back-patch to all supported branches, as we did with the previous fix.
Yuya Watari
Discussion: https://postgr.es/m/CAJ2pMkbkkFw2hb9Qb1Zj8d06EhWAQXFLy73St4qWv6aX=vqnjw@mail.gmail.com
If there is the WAL page that the continuation WAL record just fits within
(i.e., the continuation record ends just at the end of the page) and
the LSN in such page is specified with -s option, previously pg_waldump
caused an assertion failure. The cause of this assertion failure was that
XLogFindNextRecord() that pg_waldump -s calls mistakenly handled
such special WAL page.
This commit changes XLogFindNextRecord() so that it can handle
such WAL page correctly.
Back-patch to all supported versions.
Author: Andrey Lepikhov
Reviewed-by: Fujii Masao, Michael Paquier
Discussion: https://postgr.es/m/99303554-5dd5-06e6-f943-b3005ccd6edd@postgrespro.ru
When sending data for logical decoding using the streaming replication
protocol via a WAL sender, the timestamp of the sent write message is
allocated at the beginning of the message when preparing for the write,
and actually computed when the write message is ready to be sent.
The timestamp was getting computed after sending the message. This
impacts anything using logical decoding, causing for example logical
replication to report mostly NULL for last_msg_send_time in
pg_stat_subscription.
This commit makes sure that the timestamp is computed before sending the
message. This is wrong since 5a991ef, so backpatch down to 9.4.
Author: Jeff Janes
Discussion: https://postgr.es/m/CAMkU=1z=WMn8jt7iEdC5sYNaPgAgOASb_OW5JYv-vMdYaJSL-w@mail.gmail.com
Backpatch-through: 9.4
WindowAgg will potentially store large numbers of input rows into
tuplestores to allow access to other rows in the frame. If the input
is coming via an explicit Sort node, then unneeded columns will
already have been discarded (since Sort requests a small tlist); but
there are idioms like COUNT(*) OVER () that result in the input not
being sorted at all, and cases where the input is being sorted by some
means other than a Sort; if we don't request a small tlist, then
WindowAgg's storage requirement is inflated by the unneeded columns.
Backpatch back to 9.6, where the current tlist handling was added.
(Prior to that, WindowAgg would always use a small tlist.)
Discussion: https://postgr.es/m/87a7ator8n.fsf@news-spur.riddles.org.uk
For a long time (since commit aed378e8d) we have had a policy to log
nothing about a connection if the client disconnects when challenged
for a password. This is because libpq-using clients will typically
do that, and then come back for a new connection attempt once they've
collected a password from their user, so that logging the abandoned
connection attempt will just result in log spam. However, this did
not work well for PAM authentication: the bottom-level function
pam_passwd_conv_proc() was on board with it, but we logged messages
at higher levels anyway, for lack of any reporting mechanism.
Add a flag and tweak the logic so that the case is silent, as it is
for other password-using auth mechanisms.
Per complaint from Yoann La Cancellera. It's been like this for awhile,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/CACP=ajbrFFYUrLyJBLV8=q+eNCapa1xDEyvXhMoYrNphs-xqPw@mail.gmail.com
get_relkind_objtype, and hence get_object_type, failed when applied to a
toast table. This is not a good thing, because it prevents reporting of
perfectly legitimate permissions errors. (At present, these functions
are in fact *only* used to determine the ObjectType argument for
acl_error() calls.) It seems best to have them fall back to returning
OBJECT_TABLE in every case where they can't determine an object type
for a pg_class entry, so do that.
In passing, make some edits to alter.c to make it more obvious that
those calls of get_object_type() are used only for error reporting.
This might save a few cycles in the non-error code path, too.
Back-patch to v11 where this issue originated.
John Hsu, Michael Paquier, Tom Lane
Discussion: https://postgr.es/m/C652D3DF-2B0C-4128-9420-FB5379F6B1E4@amazon.com
Rearrange the logic in record_image_cmp() and record_image_eq() to
error out on unexpected typlens (either not supported there or
completely invalid due to corruption). Barring corruption, this is
not possible today but it seems more future-proof and robust to fix
this.
Reported-by: Peter Geoghegan <pg@bowt.ie>
Commit 8af1624e3 introduced a warning about possibly returning
without a value, on compilers that don't realize that ereport(ERROR)
doesn't return. Tweak the code to avoid that.
Per buildfarm. Back-patch to 9.6, like the aforesaid commit.
Using incorrect, or just mismatched, dictionary and affix files
could result in a crash, due to failure to cross-check offsets
obtained from the file. Add necessary validation, as well as
some Asserts for future-proofing.
Per bug #16050 from Alexander Lakhin. Back-patch to 9.6 where the
problem was introduced.
Arthur Zakirov, per initial investigation by Tomas Vondra
Discussion: https://postgr.es/m/16050-024ae722464ab604@postgresql.org
Discussion: https://postgr.es/m/20191013012610.2p2fp3zzpoav7jzf@development
When using CREATE TABLE for a new partition, the partitioned indexes of
the parent are created automatically in a fashion similar to LIKE
INDEXES. The new partition and its parent use a mapping for attribute
numbers for this operation, and while the mapping was correctly built,
its length was defined as the number of attributes of the newly-created
child, and not the parent. If the parent includes dropped columns, this
could cause failures.
This is wrong since 8b08f7d which has introduced the concept of
partitioned indexes, so backpatch down to 11.
Reported-by: Wyatt Alt
Author: Michael Paquier
Reviewed-by: Amit Langote
Discussion: https://postgr.es/m/CAGem3qCcRmhbs4jYMkenYNfP2kEusDXvTfw-q+eOhM0zTceG-g@mail.gmail.com
Backpatch-through: 11
When a backend exits, it gets deleted from the syncrep queue if present.
The queue was checked without SyncRepLock taken in exclusive mode, so it
would have been possible for a backend to remove itself after a WAL
sender already did the job. Fix this issue based on a suggestion from
Fujii Masao, by first checking the queue without the lock. Then, if the
backend is present in the queue, take the lock and perform an additional
lookup check before doing the element deletion.
Author: Dongming Liu
Reviewed-by: Kyotaro Horiguchi, Fujii Masao, Michael Paquier
Discussion: https://postgr.es/m/a0806273-8bbb-43b3-bbe1-c45a58f6ae21.lingce.ldm@alibaba-inc.com
Backpatch-through: 9.4
It appears that libxml2 doesn't bother to set the "children" field of
an XML_NAMESPACE_DECL node to null; that field just contains garbage.
In v10 and v11, this can result in a crash in XMLTABLE(). The rewrite
done in commit 251cf2e27 fixed this, somewhat accidentally, in v12.
We're not going to back-patch 251cf2e27, however. The case apparently
doesn't have wide use, so rather than risk introducing other problems,
just add a safety check to throw an error.
Even though no bug manifests in v12/HEAD, add the relevant test case
there too, to prevent future regressions.
Chapman Flack (per private report)
Any callback set would have no meaning in the context of an exception.
As an autovacuum worker exits quickly in this context, this could be
only an issue within EmitErrorReport(), where the elog hook is for
example called. That's unlikely to going to be a problem, but let's be
clean and consistent with other code paths handling exceptions. This is
present since 2909419, which introduced autovacuum.
Author: Ashwin Agrawal
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/CALfoeisM+_+dgmAdAOHAu0k-ZpEHHqSSG=GRf3pKJGm8OqWX0w@mail.gmail.com
Backpatch-through: 9.4
recovery_min_apply_delay parameter is intended for use with streaming
replication deployments. However, the document clearly explains that
the parameter will be honored in all cases if it's specified. So it should
take effect even if in archive recovery. But, previously, archive recovery
with recovery_min_apply_delay enabled always failed, and caused assertion
failure if --enable-caasert is enabled.
The cause of this problem is that; the ownership of recoveryWakeupLatch
that recovery_min_apply_delay uses was taken only when standby mode
is requested. So unowned latch could be used in archive recovery, and
which caused the failure.
This commit changes recovery code so that the ownership of
recoveryWakeupLatch is taken even in archive recovery. Which prevents
archive recovery with recovery_min_apply_delay from failing.
Back-patch to v9.4 where recovery_min_apply_delay was added.
Author: Fujii Masao
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CAHGQGwEyD6HdZLfdWc+95g=VQFPR4zQL4n+yHxQgGEGjaSVheQ@mail.gmail.com
The timestamp tracking the last moment a message is received in a
logical replication worker was initialized in each loop checking if a
message was received or not, causing wal_receiver_timeout to be ignored
in basically any logical replication deployments. This also broke the
ping sent to the server when reaching half of wal_receiver_timeout.
This simply moves the initialization of the timestamp out of the apply
loop to the beginning of LogicalRepApplyLoop().
Reported-by: Jehan-Guillaume De Rorthais
Author: Julien Rouhaud
Discussion: https://postgr.es/m/CAOBaU_ZHESFcWva8jLjtZdCLspMj7vqaB2k++rjHLY897ZxbYw@mail.gmail.com
Backpatch-through: 10
Logical walsender should exit when it catches up with sending WAL during
shutdown; but there was a rare corner case when it failed to because of
a race condition that puts it back to wait for more WAL instead -- but
since there wasn't any, it'd not shut down immediately. It would only
continue the shutdown when wal_sender_timeout terminates the sleep,
which causes annoying waits during shutdown procedure. Restructure the
code so that we no longer forget to set WalSndCaughtUp in that case.
This was an oversight in commit c6c333436.
Backpatch all the way down to 9.4.
Author: Craig Ringer, Álvaro Herrera
Discussion: https://postgr.es/m/CAMsr+YEuz4XwZX_QmnX_-2530XhyAmnK=zCmicEnq1vLr0aZ-g@mail.gmail.com
Otherwise it can be hard to see where an error is coming from, when
the parallel worker sets all the GUCs that it received from the
leader. Bug #15726. Back-patch to 9.5, where RestoreGUCState()
appeared.
Reported-by: Tiago Anastacio
Reviewed-by: Daniel Gustafsson, Tom Lane
Discussion: https://postgr.es/m/15726-6d67e4fa14f027b3%40postgresql.org
Commits 801c2dc7 and 801c2dc7 made it possible for vacuum to
try to freeze a multixact that is still running. That was
prevented by a check, but raised an error. Repair.
Back-patch all the way.
Author: Nathan Bossart, Jeremy Schneider
Reported-by: Jeremy Schneider
Reviewed-by: Jim Nasby, Thomas Munro
Discussion: https://postgr.es/m/DAFB8AFF-2F05-4E33-AD7F-FF8B0F760C17%40amazon.com
The file descriptor was opened with read-only to fsync a regular file,
which would cause EBADFD errors on some platforms.
This is similar to the recent fix done by a586cc4b (which was broken by
me with 82a5649), except that I noticed this issue while monitoring the
backend code for similar mistakes. Backpatch to 9.4, as this has been
introduced since logical decoding exists as of b89e151.
Author: Michael Paquier
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/20191006045548.GA14532@paquier.xyz
Backpatch-through: 9.4
The postmaster's code path for spawning a bgworker neglected to check
whether we already have the max number of live child processes. That's
a bit hard to hit, since it would necessarily be a transient condition;
but if we do, AssignPostmasterChildSlot() fails causing a postmaster
crash, as seen in a report from Bhargav Kamineni.
To fix, invoke canAcceptConnections() in the bgworker code path, as we
do in the other code paths that spawn children. Since we don't want
the same pmState tests in this case, add a child-process-type parameter
to canAcceptConnections() so that it can know what to do.
Back-patch to 9.5. In principle the same hazard exists in 9.4, but the
code is enough different that this patch wouldn't quite fix it there.
Given the tiny usage of bgworkers in that branch it doesn't seem worth
creating a variant patch for it.
Discussion: https://postgr.es/m/18733.1570382257@sss.pgh.pa.us
