ecpglib has been calling it once per SQL query and once per EXEC SQL GET
DESCRIPTOR. Instead, if newlocale() has not succeeded before, call it
while establishing a connection. This mitigates three problems:
- If newlocale() failed in EXEC SQL GET DESCRIPTOR, the command silently
proceeded without the intended locale change.
- On AIX, each newlocale()+freelocale() cycle leaked memory.
- newlocale() CPU usage may have been nontrivial.
Fail the connection attempt if newlocale() fails. Rearrange
ecpg_do_prologue() to validate the connection before its uselocale().
The sort of program that may regress is one running in an environment
where newlocale() fails. If that program establishes connections
without running SQL statements, it will stop working in response to this
change. I'm betting against the importance of such an ECPG use case.
Most SQL execution (any using ECPGdo()) has long required newlocale()
success, so there's little a connection could do without newlocale().
Back-patch to v10 (all supported versions).
Reviewed by Tom Lane. Reported by Guillaume Lelarge.
Discussion: https://postgr.es/m/20220101074055.GA54621@rfd.leadboat.com
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
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
Previously, we encoded both NULL and the first byte at the base address
as 0. That confusion led to the assertion in commit e07d4ddc, which
failed when min_dynamic_shared_memory was used. Give them distinct
encodings, by switching to 1-based offsets for non-NULL pointers. Also
improve macro hygiene in passing (missing/misplaced parentheses), and
remove open-coded access to the raw offset value from freepage.c/h.
Although e07d4ddc was back-patched to 10, the only code that actually
makes use of relptr at the base address arrived in 84b1c63a, so no need
to back-patch further than 14 for now.
Reported-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/20220519193839.GT19626%40telsasoft.com
Since commit 6a2a70a02, we've used signalfd() to receive latch wakeups
when building with WAIT_USE_EPOLL (default for Linux and illumos), and
our traditional self-pipe when falling back to WAIT_USE_POLL (default
for other Unixes with neither epoll() nor kqueue()).
Unexplained hangs and kernel panics have been reported on illumos
systems, apparently linked to this use of signalfd(), leading illumos
users and build farm members to have to define WAIT_USE_POLL explicitly
as a work-around. A bug report exists at
https://www.illumos.org/issues/13700 but no fix is available yet.
Let's provide a way for illumos users to go back to self-pipes with
epoll(), like releases before 14, and choose that by default. No change
for Linux users. To help with development/debugging, macros
WAIT_USE_{EPOLL,POLL} and WAIT_USE_{SIGNALFD,SELF_PIPE} can be defined
explicitly to override the defaults.
Back-patch to 14, where we started using signalfd().
Reported-by: Japin Li <japinli@hotmail.com>
Reported-by: Olaf Bohlen <olbohlen@eenfach.de> (off-list)
Reviewed-by: Japin Li <japinli@hotmail.com>
Discussion: https://postgr.es/m/MEYP282MB1669C8D88F0997354C2313C1B6CA9%40MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM
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
Remove the need to edit back-branch-specific code sites when
back-patching the addition of a PostgreSQL::Test::Utils symbol. Replace
per-symbol, incomplete alias lists. Give old and new package names the
same EXPORT and EXPORT_OK semantics. Back-patch to v10 (all supported
versions).
Reviewed by Andrew Dunstan.
Discussion: https://postgr.es/m/20220622072144.GD4167527@rfd.leadboat.com
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
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
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
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
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
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
If an application executed operations like EXEC SQL PREPARE
without having first established a database connection, it could
get a core dump instead of the expected clean failure. This
occurred because we did "pthread_getspecific(actual_connection_key)"
without ever having initialized the TSD key actual_connection_key.
The results of that are probably platform-specific, but at least
on Linux it often leads to a crash.
To fix, add calls to ecpg_pthreads_init() in the code paths that
might use actual_connection_key uninitialized. It's harmless
(and hopefully inexpensive) to do that more than once.
Per bug #17514 from Okano Naoki. The problem's ancient, so
back-patch to all supported branches.
Discussion: https://postgr.es/m/17514-edd4fad547c5692c@postgresql.org
The previous wording was "the underlying data type's default collation
is used", which is wrong or at least misleading. The domain inherits
the base type's collation behavior, which if "default" actually can
mean that we use some non-default collation obtained from elsewhere.
Per complaint from Jian He.
Discussion: https://postgr.es/m/CACJufxHMR8_4WooDPjjvEdaxB2hQ5a49qthci8fpKP0MKemVRQ@mail.gmail.com
This reverts commits a04ccf6df et al. in the back branches only.
There was some disagreement already over whether to back-patch
157f8739a, on the grounds that it is the sort of behavioral
change that we don't like to back-patch. Furthermore, it now
looks like the logic needs some more work, which we don't have
time for before the upcoming 14.4 release. Revert for now, and
perhaps reconsider later.
Discussion: https://postgr.es/m/17504-76b68018e130415e@postgresql.org
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
The patch introducing jsonpath dropped a para about that between
two related examples, and didn't bother updating the introductory
sentences that it falsified. The grammar was pretty shaky as well.
Bug #17512 highlighted that a suitably broken data type could cause the
backend to crash if either the hash function or equality function were in
someway non-deterministic based on their input values. Such a data type
could cause a crash of the backend due to some code which assumes that
we'll always find a hash table entry corresponding to an item in the
Memoize LRU list.
Here we remove the assumption that we'll always find the entry
corresponding to the given LRU list item and add run-time checks to verify
we have found the given item in the cache.
This is not a fix for bug #17512, but it will turn the crash reported by
that bug report into an internal ERROR.
Reported-by: Ales Zeleny
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CAApHDvpxFSTwvoYWT7kmFVSZ9zLAeHb=S9vrz=RExMgSkQNWqw@mail.gmail.com
Backpatch-through: 14, where Memoize was added.
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
An error PGresult generated by libpq itself, such as a report of
connection loss, won't have broken-down error fields.
should_processing_continue() blithely assumed that
PG_DIAG_SEVERITY_NONLOCALIZED would always be present, and would
dump core if it wasn't.
Per grepping to see if 6d157e7cb's mistake was repeated elsewhere.
An error PGresult generated by libpq itself, such as a report of
connection loss, won't have broken-down error fields.
ecpg_raise_backend() blithely assumed that PG_DIAG_MESSAGE_PRIMARY
would always be present, and would end up passing a NULL string
pointer to snprintf when it isn't. That would typically crash
before 3779ac62d, and it would fail to provide a useful error report
in any case. Best practice is to substitute PQerrorMessage(conn)
in such cases, so do that.
Per bug #17421 from Masayuki Hirose. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/17421-790ff887e3188874@postgresql.org
psql --single-transaction is able to handle multiple -c and -f switches
in a single transaction since d5563d7d, but this had the surprising
behavior of forcing a transaction COMMIT even if psql failed with an
error in the client (for example incorrect path given to \copy), which
would generate an error, but still commit any changes that were already
applied in the backend. This commit makes the behavior more consistent,
by enforcing a transaction ROLLBACK if any commands fail, both
client-side and backend-side, so as no changes are applied if one error
happens in any of them.
Some tests are added on HEAD to provide some coverage about all that.
Backend-side errors are unreliable as IPC::Run can complain on SIGPIPE
if psql quits before reading a query result, but that should work
properly in the case where any errors come from psql itself, which is
what the original report is about.
Reported-by: Christoph Berg
Author: Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/17504-76b68018e130415e@postgresql.org
Backpatch-through: 10
The previous entry invited confusion between what uniq() does
by itself and what it does when combined with sort(). The latter
usage is pretty useful so we should show it, but add an additional
example to clarify the results of uniq() alone.
Per suggestion from Martin Kalcher. Back-patch to v13, where
we switched to formatting that supports multiple examples.
Discussion: https://postgr.es/m/165407884456.573551.8779012279828726162@wrigleys.postgresql.org
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
Perl 5.36 has reclassified the warning condition that this test
case used, so that the expected error fails to appear. Tweak
the test so it instead exercises a case that's handled the same
way in all Perl versions of interest.
This appears to meet our standards for back-patching into
out-of-support branches: it changes no user-visible behavior
but enables testing of old branches with newer tools.
Hence, back-patch as far as 9.2.
Dagfinn Ilmari Mannsåker, per report from Jitka Plesníková.
Discussion: https://postgr.es/m/564579.1654093326@sss.pgh.pa.us
The example given for anyelement <@ anymultirange didn't return
true as claimed; adjust it so it does.
In passing, change a couple of sample results where the modern
numeric-based logic produces a different number of trailing zeroes
than before.
Erik Rijkers
Discussion: https://postgr.es/m/cc35735d-1ec1-5bb3-9e27-cddbab7afa23@xs4all.nl
The PostgreSQL limitations section of the documents mentioned the limit
on the number of columns that can exist in a table. Users might be
surprised to find that there's also a limit on the number of columns that
can exist in a targetlist. Users may experience restrictions which
surprise them if they happened to select a large number of columns from
several tables with many columns. Here we document that there is a
limitation on this and mention what that limit actually is.
Wording proposal by Alvaro Herrera
Reported-by: Vladimir Sitnikov
Author: Dave Crammer
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CAB=Je-E18aTYpNqje4mT0iEADpeGLSzwUvo3H9kRRuDdsNo4aQ@mail.gmail.com
Backpatch-through: 12, where the limitations section was added
This reverts commit d9d076222f "VACUUM: ignore indexing operations
with CONCURRENTLY".
These changes caused indexes created with the CONCURRENTLY option to
miss heap tuples that were HOT-updated and HOT-pruned during the index
creation. Before these changes, HOT pruning would have been prevented
by the Xmin of the transaction creating the index, but because this
change was precisely to allow the Xmin to move forward ignoring that
backend, now other backends scanning the table can prune them. This is
not a problem for VACUUM (which requires a lock that conflicts with a
CREATE INDEX CONCURRENTLY operation), but HOT-prune can definitely
occur. In other words, Xmin advancement was sped up, but at the cost of
corrupting the resulting index.
Regrettably, this means that the new feature in PG14 that RIC/CIC on
very large tables no longer force VACUUM to retain very old tuples goes
away. We might try to implement it again in a later release, but for
now the risk of indexes missing tuples is too high and there's no easy
fix.
Backpatch to 14, where this change appeared.
Reported-by: Peter Slavov <pet.slavov@gmail.com>
Diagnosys-by: Andrey Borodin <x4mmm@yandex-team.ru>
Diagnosys-by: Michael Paquier <michael@paquier.xyz>
Diagnosys-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/17485-396609c6925b982d%40postgresql.org
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
runtime.sgml contains a passing reference to the minimum server
version that pg_dump[all] can dump from. That was 7.0 for many
years, but when 64f3524e2 raised it to 8.0, we missed updating this
bit. Then when 30e7c175b raised it to 9.2, we missed it again.
Given that track record, I'm not too hopeful that we'll remember
to fix this in future changes ... but for now, make the docs match
reality in each branch.
Noted by Daniel Westermann.
Discussion: https://postgr.es/m/GV0P278MB041917EB3E2FE8704B5AE2C6D2DC9@GV0P278MB0419.CHEP278.PROD.OUTLOOK.COM
The information generated when track_activities is accessible to
superusers, roles with the privileges of pg_read_all_stats, as well as
roles one has the privileges of. The original text did not outline the
last point, while the change done in ac1ae47 was unclear about the
second point.
Per discussion with Nathan Bossart.
Discussion: https://postgr.es/m/20220521185743.GA886636@nathanxps13
Backpatch-through: 10
In the codepath when no encoding conversion is required, the check for
incomplete character at the end of input incorrectly used server
encoding's max character length, instead of the client's. Usually the
server and client encodings are the same when we're not performing
encoding conversion, but SQL_ASCII is an exception.
In the passing, also fix some outdated comments that still talked about
the old COPY protocol. It was removed in v14.
Per bug #17501 from Vitaly Voronov. Backpatch to v14 where this was
introduced.
Discussion: https://www.postgresql.org/message-id/17501-128b1dd039362ae6@postgresql.org
The form taking anymultirange had not been documented. This was
fixed in HEAD in b21c4cf95, but that should have been back-patched
to v14 since the function was added there. Do so now.
Also, the form taking anyrange was incorrectly documented as
returning anymultirange, when it returns anyrange.
Remove b21c4cf95 from the v15 release notes, since it no longer
qualifies as new-in-v15.
Noted by Shay Rojansky.
Discussion: https://postgr.es/m/CADT4RqAktzP7t6SFf0Xqm9YhahzvsmxFbzXe-gFOd=+_CHm0JA@mail.gmail.com
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
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
Foreign tables can be partitioned, but previous documentation commits
left the syntax synopsis both incomplete and incorrect.
Justin Pryzby and Amit Langote
Discussion: http://postgr.es/m/20220521130922.GX19626@telsasoft.com
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
The description of track_activities mentioned that it is visible to
superusers and that the information related to the current session can
be seen, without telling about pg_read_all_stats. Roles that are
granted the privileges of pg_read_all_stats can also see this
information, so mention it in the docs.
Author: Ian Barwick
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/CAB8KJ=jhPyYFu-A5r-ZGP+Ax715mUKsMxAGcEQ9Cx_mBAmrPow@mail.gmail.com
Backpatch-through: 10
Noah Misch
Thomas Munro
Heikki Linnakangas
Amit Kapila
Bruce Momjian
Tom Lane
Peter Eisentraut
David Rowley
Michael Paquier
Etsuro Fujita
Magnus Hagander
Alvaro Herrera
Robert Haas