If an aggregate function call contains a sub-select that has
an RTE referencing a CTE outside the aggregate, we must treat
that reference like a Var referencing the CTE's query level
for purposes of determining the aggregate's level. Otherwise
we might reach the nonsensical conclusion that the aggregate
should be evaluated at some query level higher than the CTE,
ending in a planner error or a broken plan tree that causes
executor failures.
Bug: #19055
Reported-by: BugForge <dllggyx@outlook.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19055-6970cfa8556a394d@postgresql.org
Backpatch-through: 13
The EvalPlanQual recheck for TID Range Scan wasn't rechecking the TID qual
still passed after following update chains. This could result in tuples
being updated or deleted by plans using TID Range Scans where the ctid of
the new (updated) tuple no longer matches the clause of the scan. This
isn't desired behavior, and isn't consistent with what would happen if the
chosen plan had used an Index or Seq Scan, and that could lead to hard to
predict behavior for scans that contain TID quals and other quals as the
planner has freedom to choose TID Range or some other non-TID scan method
for such queries, and the chosen plan could change at any moment.
Here we fix this by properly implementing the recheck function for TID
Range Scans.
Backpatch to 14, where TID Range Scans were added
Reported-by: Sophie Alpert <pg@sophiebits.com>
Author: Sophie Alpert <pg@sophiebits.com>
Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/4a6268ff-3340-453a-9bf5-c98d51a6f729@app.fastmail.com
Backpatch-through: 14
The EvalPlanQual recheck for TID Scan wasn't rechecking the TID qual
still passed after following update chains. This could result in tuples
being updated or deleted by plans using TID Scans where the ctid of the
new (updated) tuple no longer matches the clause of the scan. This isn't
desired behavior, and isn't consistent with what would happen if the
chosen plan had used an Index or Seq Scan, and that could lead to hard to
predict behavior for scans that contain TID quals and other quals as the
planner has freedom to choose TID or some other scan method for such
queries, and the chosen plan could change at any moment.
Here we fix this by properly implementing the recheck function for TID
Scans.
Backpatch to 13, oldest supported version
Reported-by: Sophie Alpert <pg@sophiebits.com>
Author: Sophie Alpert <pg@sophiebits.com>
Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/4a6268ff-3340-453a-9bf5-c98d51a6f729@app.fastmail.com
Backpatch-through: 13
JsonConstructorExpr can produce non-NULL output with a NULL input, so
it should be treated as a non-strict construct. Failing to do so can
lead to incorrect query behavior.
For example, in the reported case, when pulling up a subquery that is
under an outer join, if the subquery's target list contains a
JsonConstructorExpr that uses subquery variables and it is mistakenly
treated as strict, it will be pulled up without being wrapped in a
PlaceHolderVar. As a result, the expression will be evaluated at the
wrong place and will not be forced to null when the outer join should
do so.
Back-patch to v16 where JsonConstructorExpr was introduced.
Bug: #19046
Reported-by: Runyuan He <runyuan@berkeley.edu>
Author: Tender Wang <tndrwang@gmail.com>
Co-authored-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/19046-765b6602b0a8cfdf@postgresql.org
Backpatch-through: 16
Commit e3ffc3e91 fixed the translation of character classes in
SIMILAR TO regular expressions. Unfortunately the fix broke a corner
case: if there is an escape character right after the opening bracket
(for example in "[\q]"), a closing bracket right after the escape
sequence would not be seen as closing the character class.
There were two more oversights: a backslash or a nested opening bracket
right at the beginning of a character class should remove the special
meaning from any following caret or closing bracket.
This bug suggests that this code needs to be more readable, so also
rename the variables "charclass_depth" and "charclass_start" to
something more meaningful, rewrite an "if" cascade to be more
consistent, and improve the commentary.
Reported-by: Dominique Devienne <ddevienne@gmail.com>
Reported-by: Stephan Springl <springl-psql@bfw-online.de>
Author: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAFCRh-8NwJd0jq6P=R3qhHyqU7hw0BTor3W0SvUcii24et+zAw@mail.gmail.com
Backpatch-through: 13
Commit a0b99fc12 caused pg_event_trigger_dropped_objects()
to not fill the object_name field for schemas, which it
should have; and caused it to fill the object_name field
for default values, which it should not have.
In addition, triggers and RLS policies really should behave
the same way as we're making column defaults do; that is,
they should have is_temporary = true if they belong to a
temporary table.
Fix those things, and upgrade event_trigger.sql's woefully
inadequate test coverage of these secondary output columns.
As before, back-patch only to v15.
Reported-by: Sergey Shinderuk <s.shinderuk@postgrespro.ru>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/bd7b4651-1c26-4d30-832b-f942fabcb145@postgrespro.ru
Backpatch-through: 15
Clang 21 shows some new compiler warnings, for example:
warning: variable 'dstsize' is uninitialized when passed as a const pointer argument here [-Wuninitialized-const-pointer]
The fix is to initialize the variables when they are defined. This is
similar to, for example, the existing situation in gistKeyIsEQ().
Discussion: https://www.postgresql.org/message-id/flat/6604ad6e-5934-43ac-8590-15113d6ae4b1%40eisentraut.org
pg_event_trigger_dropped_objects() would report a column default
object with is_temporary = false, even if it belongs to a
temporary table. This seems clearly wrong, so adjust it to
report the table's temp-ness.
While here, refactor EventTriggerSQLDropAddObject to make its
handling of namespace objects less messy and avoid duplication
of the schema-lookup code. And add some explicit test coverage
of dropped-object reports for dependencies of temp tables.
Back-patch to v15. The bug exists further back, but the
GetAttrDefaultColumnAddress function this patch depends on does not,
and it doesn't seem worth adjusting it to cope with the older code.
Author: Antoine Violin <violin.antuan@gmail.com>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAFjUV9x3-hv0gihf+CtUc-1it0hh7Skp9iYFhMS7FJjtAeAptA@mail.gmail.com
Backpatch-through: 15
If the hash functions used for hashing tuples leaked any memory,
we failed to clean that up, resulting in query-lifespan memory
leakage in queries using hashed subplans. One way that could
happen is if the values being hashed require de-toasting, since
most of our hash functions don't trouble to clean up de-toasted
inputs.
Prior to commit bf6c614a2, this leakage was largely masked
because TupleHashTableMatch would reset hashtable->tempcxt
(via execTuplesMatch). But it doesn't do that anymore, and
that's not really the right place for this anyway: doing it
there could reset the tempcxt many times per hash lookup,
or not at all. Instead put reset calls into ExecHashSubPlan
and buildSubPlanHash. Along the way to that, rearrange
ExecHashSubPlan so that there's just one place to call
MemoryContextReset instead of several.
This amounts to accepting the de-facto API spec that the caller
of the TupleHashTable routines is responsible for resetting the
tempcxt adequately often. Although the other callers seem to
get this right, it was not documented anywhere, so add a comment
about it.
Bug: #19040
Reported-by: Haiyang Li <mohen.lhy@alibaba-inc.com>
Author: Haiyang Li <mohen.lhy@alibaba-inc.com>
Reviewed-by: Fei Changhong <feichanghong@qq.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19040-c9b6073ef814f48c@postgresql.org
Backpatch-through: 13
The startup process does not process shared invalidation messages, only
sending them, and never calls AtEOXact_SMgr() which clean up any
unpinned SMgrRelations. Hence, it is never able to free SMgrRelations
on a periodic basis, bloating its hashtable over time.
Like the checkpointer and the bgwriter, this commit takes a conservative
approach by freeing periodically SMgrRelations when replaying a
checkpoint record, either online or shutdown, so as the startup process
has a way to perform a periodic cleanup.
Issue caused by 21d9c3ee4e, so backpatch down to v17.
Author: Jingtang Zhang <mrdrivingduck@gmail.com>
Reviewed-by: Yuhang Qiu <iamqyh@gmail.com>
Discussion: https://postgr.es/m/28C687D4-F335-417E-B06C-6612A0BD5A10@gmail.com
Backpatch-through: 17
A new pgstats entry is created as a two-step process:
- The entry is looked at in the shared hashtable of pgstats, and is
inserted if not found.
- When not found and inserted, its fields are then initialized. This
part include a DSA chunk allocation for the stats data of the new entry.
As currently coded, if the DSA chunk allocation fails due to an
out-of-memory failure, an ERROR is generated, leaving in the pgstats
shared hashtable an inconsistent entry due to the first step, as the
entry has already been inserted in the hashtable. These broken entries
can then be found by other backends, crashing them.
There are only two callers of pgstat_init_entry(), when loading the
pgstats file at startup and when creating a new pgstats entry. This
commit changes pgstat_init_entry() so as we use dsa_allocate_extended()
with DSA_ALLOC_NO_OOM, making it return NULL on allocation failure
instead of failing. This way, a backend failing an entry creation can
take appropriate cleanup actions in the shared hashtable before throwing
an error. Currently, this means removing the entry from the shared
hashtable before throwing the error for the allocation failure.
Out-of-memory errors unlikely happen in the wild, and we do not bother
with back-patches when these are fixed, usually. However, the problem
dealt with here is a degree worse as it breaks the shared memory state
of pgstats, impacting other processes that may look at an inconsistent
entry that a different process has failed to create.
Author: Mikhail Kot <mikhail.kot@databricks.com>
Discussion: https://postgr.es/m/CAAi9E7jELo5_-sBENftnc2E8XhW2PKZJWfTC3i2y-GMQd2bcqQ@mail.gmail.com
Backpatch-through: 15
When executing a MERGE UPDATE action, if there is more than one
concurrent update of the target row, the lock-and-retry code would
sometimes incorrectly identify the latest version of the target tuple,
leading to incorrect results.
This was caused by using the ctid field from the TM_FailureData
returned by table_tuple_lock() in a case where the result was TM_Ok,
which is unsafe because the TM_FailureData struct is not guaranteed to
be fully populated in that case. Instead, it should use the tupleid
passed to (and updated by) table_tuple_lock().
To reduce the chances of similar errors in the future, improve the
commentary for table_tuple_lock() and TM_FailureData to make it
clearer that table_tuple_lock() updates the tid passed to it, and most
fields of TM_FailureData should not be relied on in non-failure cases.
An exception to this is the "traversed" field, which is set in both
success and failure cases.
Reported-by: Dmitry <dsy.075@yandex.ru>
Author: Yugo Nagata <nagata@sraoss.co.jp>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/1570d30e-2b95-4239-b9c3-f7bf2f2f8556@yandex.ru
Backpatch-through: 15
Per buildfarm member wrasse, void function cannot return a value.
This only affects v13-v17, where an ABI-compatible wrapper function
was added.
Backpatch-through: 13-17
If an INSERT has an ON CONFLICT DO UPDATE clause, the executor must
check that the target relation supports UPDATE as well as INSERT. In
particular, it must check that the target relation has a REPLICA
IDENTITY if it publishes updates. Formerly, it was not doing this
check, which could lead to silently breaking replication.
Fix by adding such a check to CheckValidResultRel(), which requires
adding a new onConflictAction argument. In back-branches, preserve ABI
compatibility by introducing a wrapper function with the original
signature.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Tested-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/OS3PR01MB57180C87E43A679A730482DF94B62@OS3PR01MB5718.jpnprd01.prod.outlook.com
Backpatch-through: 13
SubPlan nodes are typically built very early, before any RelOptInfos
have been constructed for the parent query level. As a result, the
simple_rel_array in the parent root has not yet been initialized.
Currently, during cost estimation of a SubPlan's testexpr, we may call
examine_variable() to look up statistical data about the expressions.
This can lead to "no relation entry for relid" errors.
To fix, pass root as NULL to cost_qual_eval() in cost_subplan(), since
the root does not yet contain enough information to safely consult
statistics.
One exception is SubPlan nodes built for the initplans of MIN/MAX
aggregates from indexes. In this case, having a NULL root is safe
because testexpr will be NULL. Additionally, an initplan will by
definition not consult anything from the parent plan.
Backpatch to all supported branches. Although the reported call path
that triggers this error is not reachable prior to v17, there's no
guarantee that other code paths -- especially in extensions -- could
not encounter the same issue when cost_qual_eval() is called with a
root that lacks a valid simple_rel_array. The test case is not
included in pre-v17 branches though.
Bug: #19037
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Diagnosed-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19037-3d1c7bb553c7ce84@postgresql.org
Backpatch-through: 13
SLRU bank locks are referred as "bank locks" or "SLRU bank locks" in the
code comments. The comments updated in this commit use the latter term.
Oversight in 53c2a97a92, that has replaced the single ControlLock by
the bank control locks.
Author: Julien Rouhaud <julien.rouhaud@free.fr>
Discussion: https://postgr.es/m/aLUT2UO8RjJOzZNq@jrouhaud
Backpatch-through: 17
It's possible that if the only live partition is concurrently dropped
and try_table_open() fails, that the bms_del_member() will pfree the
live_parts Bitmapset. Since the bms_del_member() call does not assign
the result back to the live_parts local variable, the while loop could
segfault as that variable would still reference the pfree'd Bitmapset.
Backpatch to 15. 52f3de874 was backpatched to 14, but there's no
bms_del_member() there due to live_parts not yet existing in RelOptInfo in
that version. Technically there's no bug in version 15 as
bms_del_member() didn't pfree when the set became empty prior to
00b41463c (from v16). Applied to v15 anyway to keep the code similar and
to avoid the bad coding pattern.
Author: Bernd Reiß <bd_reiss@gmx.at>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/6b88f27a-c45c-4826-8e37-d61a04d90182@gmx.at
Backpatch-through: 15
Commit 4b754d6c1 introduced the concept of an excludeOnly scan key,
which cannot select matching index entries but can reject
non-matching tuples, for example a tsquery such as '!term'. There are
poorly-documented assumptions that such scan keys do not appear as the
first scan key. ginNewScanKey did nothing to ensure that, however,
with the result that certain GIN index searches could go into an
infinite loop while apparently-equivalent queries with the clauses in
a different order were fine.
Fix by teaching ginNewScanKey to place all excludeOnly scan keys
after all not-excludeOnly ones. So far as we know at present,
it might be sufficient to avoid the case where the very first
scan key is excludeOnly; but I'm not very convinced that there
aren't other dependencies on the ordering.
Bug: #19031
Reported-by: Tim Wood <washwithcare@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19031-0638148643d25548@postgresql.org
Backpatch-through: 13
The CHECK_FOR_INTERRUPTS call in gingetbitmap turns out to be
inadequate to prevent a long uninterruptible loop, because
we now know a case where looping occurs within scanGetItem.
While the next patch will fix the bug that caused that, it
seems foolish to assume that no similar patterns are possible.
Let's do the CFI within scanGetItem's retry loop, instead.
This demonstrably allows canceling out of the loop exhibited
in bug #19031.
Bug: #19031
Reported-by: Tim Wood <washwithcare@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19031-0638148643d25548@postgresql.org
Backpatch-through: 13
Temporary relations may share the same RelFileNumber with a permanent
relation, or other temporary relations associated with other sessions.
Being able to uniquely identify a temporary relation would require
RelidByRelfilenumber() to know about the proc number of the temporary
relation it wants to identify, something it is not designed for since
its introduction in f01d1ae3a1.
There are currently three callers of RelidByRelfilenumber():
- autoprewarm.
- Logical decoding, reorder buffer.
- pg_filenode_relation(), that attempts to find a relation OID based on
a tablespace OID and a RelFileNumber.
This makes the situation problematic particularly for the first two
cases, leading to the possibility of random ERRORs due to
inconsistencies that temporary relations can create in the cache
maintained by RelidByRelfilenumber(). The third case should be less of
an issue, as I suspect that there are few direct callers of
pg_filenode_relation().
The window where the ERRORs are happen is very narrow, requiring an OID
wraparound to create a lookup conflict in RelidByRelfilenumber() with a
temporary table reusing the same OID as another relation already cached.
The problem is easier to reach in workloads with a high OID consumption
rate, especially with a higher number of temporary relations created.
We could get pg_filenode_relation() and RelidByRelfilenumber() to work
with temporary relations if provided the means to identify them with an
optional proc number given in input, but the years have also shown that
we do not have a use case for it, yet. Note that this could not be
backpatched if pg_filenode_relation() needs changes. It is simpler to
ignore temporary relations.
Reported-by: Shenhao Wang <wangsh.fnst@fujitsu.com>
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-By: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Reviewed-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-By: Takamichi Osumi <osumi.takamichi@fujitsu.com>
Reviewed-By: Michael Paquier <michael@paquier.xyz>
Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com>
Reported-By: Shenhao Wang <wangsh.fnst@fujitsu.com>
Discussion: https://postgr.es/m/bbaaf9f9-ebb2-645f-54bb-34d6efc7ac42@fujitsu.com
Backpatch-through: 13
Some replication slot manipulations (logical decoding via SQL,
advancing) were failing an assertion when releasing a slot in
single-user mode, because active_pid was not set in a ReplicationSlot
when its slot is acquired.
ReplicationSlotAcquire() has some logic to be able to work with the
single-user mode. This commit sets ReplicationSlot->active_pid to
MyProcPid, to let the slot-related logic fall-through, considering the
single process as the one holding the slot.
Some TAP tests are added for various replication slot functions with the
single-user mode, while on it, for slot creation, drop, advancing, copy
and logical decoding with multiple slot types (temporary, physical vs
logical). These tests are skipped on Windows, as direct calls of
postgres --single would fail on permission failures. There is no
platform-specific behavior that needs to be checked, so living with this
restriction should be fine. The CI is OK with that, now let's see what
the buildfarm tells.
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Mutaamba Maasha <maasha@gmail.com>
Discussion: https://postgr.es/m/OSCPR01MB14966ED588A0328DAEBE8CB25F5FA2@OSCPR01MB14966.jpnprd01.prod.outlook.com
Backpatch-through: 13
The DROP SUBSCRIPTION command performs several operations: it stops the
subscription workers, removes subscription-related entries from system
catalogs, and deletes the replication slot on the publisher server.
Previously, this command acquired an AccessExclusiveLock on
pg_subscription before initiating these steps.
However, while holding this lock, the command attempts to connect to the
publisher to remove the replication slot. In cases where the connection is
made to a newly created database on the same server as subscriber, the
cache-building process during connection tries to acquire an
AccessShareLock on pg_subscription, resulting in a self-deadlock.
To resolve this issue, we reduce the lock level on pg_subscription during
DROP SUBSCRIPTION from AccessExclusiveLock to RowExclusiveLock. Earlier,
the higher lock level was used to prevent the launcher from starting a new
worker during the drop operation, as a restarted worker could become
orphaned.
Now, instead of relying on a strict lock, we acquire an AccessShareLock on
the specific subscription being dropped and re-validate its existence
after acquiring the lock. If the subscription is no longer valid, the
worker exits gracefully. This approach avoids the deadlock while still
ensuring that orphan workers are not created.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 13
Discussion: https://postgr.es/m/18988-7312c868be2d467f@postgresql.org
This function uses an argument named "maxsize" that is only used in
assertions, being set once outside the assertion area. Recent gcc
versions with -Wunused-but-set-parameter complain about a warning when
building without assertions enabled, because of that.
In order to fix this issue, PG_USED_FOR_ASSERTS_ONLY is added to the
function argument of SerializeClientConnectionInfo(), which is the first
time we are doing so in the tree. The CI is fine with the change, but
let's see what the buildfarm has to say on the matter.
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Jacob Champion <jchampion@postgresql.org>
Discussion: https://postgr.es/m/pevajesswhxafjkivoq3yvwxga77tbncghlf3gq5fvchsvfuda@6uivg25sb3nx
Backpatch-through: 16
It turns out that on some platforms (at least current macOS, NetBSD,
OpenBSD) semget(2) will return EINVAL if there is a pre-existing
semaphore set with the same key and too few semaphores. Our code
expects EEXIST in that case and treats EINVAL as a hard failure,
resulting in failure during initdb or postmaster start.
POSIX does document EINVAL for too-few-semaphores-in-set, and is
silent on its priority relative to EEXIST, so this behavior arguably
conforms to spec. Nonetheless it's quite problematic because EINVAL
is also documented to mean that nsems is greater than the system's
limit on the number of semaphores per set (SEMMSL). If that is
where the problem lies, retrying would just become an infinite loop.
To resolve this contradiction, retry after EINVAL, but also install a
loop limit that will make us give up regardless of the specific errno
after trying 1000 different keys. (1000 is a pretty arbitrary number,
but it seems like it should be sufficient.) I like this better than
the previous infinite-looping behavior, since it will also keep us out
of trouble if (say) we get EACCES due to a system-level permissions
problem rather than anything to do with a specific semaphore set.
This problem has only been observed in the field in PG 17, which uses
a higher nsems value than other branches (cf. 38da05346, 810a8b1c8).
That makes it possible to get the failure if a new v17 postmaster
has a key collision with an existing postmaster of another branch.
In principle though, we might see such a collision against a semaphore
set created by some other application, in which case all branches are
vulnerable on these platforms. Hence, backpatch.
Reported-by: Gavin Panella <gavinpanella@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CALL7chmzY3eXHA7zHnODUVGZLSvK3wYCSP0RmcDFHJY8f28Q3g@mail.gmail.com
Backpatch-through: 13
Commit e2d4ef8de8 (the fix for CVE-2017-7484) added security checks
to the selectivity estimation functions to prevent them from running
user-supplied operators on data obtained from pg_statistic if the user
lacks privileges to select from the underlying table. In cases
involving inheritance/partitioning, those checks were originally
performed against the child RTE (which for plain inheritance might
actually refer to the parent table). Commit 553d2ec271 then extended
that to also check the parent RTE, allowing access if the user had
permissions on either the parent or the child. It turns out, however,
that doing any checks using the child RTE is incorrect, since
securityQuals is set to NULL when creating an RTE for an inheritance
child (whether it refers to the parent table or the child table), and
therefore such checks do not correctly account for any RLS policies or
security barrier views. Therefore, do the security checks using only
the parent RTE. This is consistent with how RLS policies are applied,
and the executor's ACL checks, both of which use only the parent
table's permissions/policies. Similar checks are performed in the
extended stats code, so update that in the same way, centralizing all
the checks in a new function.
In addition, note that these checks by themselves are insufficient to
ensure that the user has access to the table's data because, in a
query that goes via a view, they only check that the view owner has
permissions on the underlying table, not that the current user has
permissions on the view itself. In the selectivity estimation
functions, there is no easy way to navigate from underlying tables to
views, so add permissions checks for all views mentioned in the query
to the planner startup code. If the user lacks permissions on a view,
a permissions error will now be reported at planner-startup, and the
selectivity estimation functions will not be run.
Checking view permissions at planner-startup in this way is a little
ugly, since the same checks will be repeated at executor-startup.
Longer-term, it might be better to move all the permissions checks
from the executor to the planner so that permissions errors can be
reported sooner, instead of creating a plan that won't ever be run.
However, such a change seems too far-reaching to be back-patched.
Back-patch to all supported versions. In v13, there is the added
complication that UPDATEs and DELETEs on inherited target tables are
planned using inheritance_planner(), which plans each inheritance
child table separately, so that the selectivity estimation functions
do not know that they are dealing with a child table accessed via its
parent. Handle that by checking access permissions on the top parent
table at planner-startup, in the same way as we do for views. Any
securityQuals on the top parent table are moved down to the child
tables by inheritance_planner(), so they continue to be checked by the
selectivity estimation functions.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Noah Misch <noah@leadboat.com>
Backpatch-through: 13
Security: CVE-2025-8713
This function is called from ATExecAttachPartition/ATExecAddInherit,
which prevent tables with row-level triggers with transition tables from
becoming partitions or inheritance children, to check if there is such a
trigger on the given table, but failed to check if a found trigger is
row-level, causing the caller functions to needlessly prevent a table
with only a statement-level trigger with transition tables from becoming
a partition or inheritance child. Repair.
Oversight in commit 501ed02cf.
Author: Etsuro Fujita <etsuro.fujita@gmail.com>
Discussion: https://postgr.es/m/CAPmGK167mXzwzzmJ_0YZ3EZrbwiCxtM1vogH_8drqsE6PtxRYw%40mail.gmail.com
Backpatch-through: 13
Commit 9e6104c66 disallowed transition tables on foreign tables, but
failed to account for cases where a foreign table is a child table of a
partitioned/inherited table on which transition tables exist, leading to
incorrect transition tuples collected from such foreign tables for
queries on the parent table triggering transition capture. This
occurred not only for inherited UPDATE/DELETE but for partitioned INSERT
later supported by commit 3d956d956, which should have handled it at
least for the INSERT case, but didn't.
To fix, modify ExecAR*Triggers to throw an error if the given relation
is a foreign table requesting transition capture. Also, this commit
fixes make_modifytable so that in case of an inherited UPDATE/DELETE
triggering transition capture, FDWs choose normal operations to modify
child foreign tables, not DirectModify; which is needed because they
would otherwise skip the calls to ExecAR*Triggers at execution, causing
unexpected behavior.
Author: Etsuro Fujita <etsuro.fujita@gmail.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CAPmGK14QJYikKzBDCe3jMbpGENnQ7popFmbEgm-XTNuk55oyHg%40mail.gmail.com
Backpatch-through: 13
Dropping twice a pgstats entry should not happen, and the error report
generated was missing the "generation" counter (tracking when an entry
is reused) that has been added in 818119afcc.
Like d92573adcb, backpatch down to v15 where this information is
useful to have, to gather more information from instances where the
problem shows up. A report has shown that this error path has been
reached on a standby based on 17.3, for a relation stats entry and an
OID close to wraparound.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/CAN4RuQvYth942J2+FcLmJKgdpq6fE5eqyFvb_PuskxF2eL=Wzg@mail.gmail.com
Backpatch-through: 15
Use Min(NBuffers, MAX_CHECKPOINT_REQUESTS) instead of NBuffers in
CheckpointerShmemSize() to match the actual array size limit set in
CheckpointerShmemInit(). This prevents wasting shared memory when
NBuffers > MAX_CHECKPOINT_REQUESTS. Also, fix the comment.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1439188.1754506714%40sss.pgh.pa.us
Author: Xuneng Zhou <xunengzhou@gmail.com>
Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com>
The result of "DirectFunctionCall1(numeric_float8, d)" is already in
Datum form, but the code was incorrectly applying PG_RETURN_FLOAT8()
to it. On machines where float8 is pass-by-reference, this would
result in complete garbage, since an unpredictable pointer value
would be treated as an integer and then converted to float. It's not
entirely clear how much of a problem would ensue on 64-bit hardware,
but certainly interpreting a float8 bitpattern as uint64 and then
converting that to float isn't the intended behavior.
As luck would have it, even the complete-garbage case doesn't break
BRIN indexes, since the results are only used to make choices about
how to merge values into ranges: at worst, we'd make poor choices
resulting in an inefficient index. Doubtless that explains the lack
of field complaints. However, users with BRIN indexes that use the
numeric_minmax_multi_ops opclass may wish to reindex in hopes of
making their indexes more efficient.
Author: Peter Eisentraut <peter@eisentraut.org>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2093712.1753983215@sss.pgh.pa.us
Backpatch-through: 14
Previously, enabling sync_replication_slots while wal_level was not set
to logical could cause the server to shut down. This was because
the postmaster performed a configuration check before launching
the slot synchronization worker and raised an ERROR if the settings
were incompatible. Since ERROR is treated as FATAL in the postmaster,
this resulted in the entire server shutting down unexpectedly.
This commit changes the postmaster to log that message with a LOG-level
instead of raising an ERROR, allowing the server to continue running
even with the misconfiguration.
Back-patch to v17, where slot synchronization was introduced.
Reported-by: Hugo DUBOIS <hdubois@scaleway.com>
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Hugo DUBOIS <hdubois@scaleway.com>
Reviewed-by: Shveta Malik <shveta.malik@gmail.com>
Discussion: https://postgr.es/m/CAH0PTU_pc3oHi__XESF9ZigCyzai1Mo3LsOdFyQA4aUDkm01RA@mail.gmail.com
Backpatch-through: 17
In ReorderBufferProcessTXN(), used to send the data of a transaction to
an output plugin, INSERT ON CONFLICT changes (INTERNAL_SPEC_INSERT) are
delayed until a confirmation record arrives (INTERNAL_SPEC_CONFIRM),
updating the change being processed.
8c58624df4 has added an extra step after processing a change to update
the progress of the transaction, by calling the callback
update_progress_txn() based on the LSN stored in a change after a
threshold of CHANGES_THRESHOLD (100) is reached. This logic has missed
the fact that for an INSERT ON CONFLICT change the data is freed once
processed, hence update_progress_txn() could be called pointing to a LSN
value that's already been freed. This could result in random crashes,
depending on the workload.
Per discussion, this issue is fixed by reusing in update_progress_txn()
the LSN from the change processed found at the beginning of the loop,
meaning that for a INTERNAL_SPEC_CONFIRM change the progress is updated
using the LSN of the INTERNAL_SPEC_CONFIRM change, and not the LSN from
its INTERNAL_SPEC_INSERT change. This is actually more correct, as we
want to update the progress to point to the INTERNAL_SPEC_CONFIRM
change.
Masahiko Sawada has found a nice trick to reproduce the issue: hardcode
CHANGES_THRESHOLD at 1 and run test_decoding (test "ddl" being enough)
on an instance running valgrind. The bug has been analyzed by Ethan
Mertz, who also originally suggested the solution used in this patch.
Issue introduced by 8c58624df4, so backpatch down to v16.
Author: Ethan Mertz <ethan.mertz@gmail.com>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/aIsQqDZ7x4LAQ6u1@paquier.xyz
Backpatch-through: 16
Currently, ALTER DATABASE/ROLE/SYSTEM RESET [ALL] with an unknown
custom GUC with a prefix reserved by MarkGUCPrefixReserved() errors
(unless a superuser runs a RESET ALL variant). This is problematic
for cases such as an extension library upgrade that removes a GUC.
To fix, simply make sure the relevant code paths explicitly allow
it. Note that we require superuser or privileges on the parameter
to reset it. This is perhaps a bit more restrictive than is
necessary, but it's not clear whether further relaxing the
requirements is safe.
Oversight in commit 88103567cb. The ALTER SYSTEM fix is dependent
on commit 2d870b4aef, which first appeared in v17. Unfortunately,
back-patching that commit would introduce ABI breakage, and while
that breakage seems unlikely to bother anyone, it doesn't seem
worth the risk. Hence, the ALTER SYSTEM part of this commit is
omitted on v15 and v16.
Reported-by: Mert Alev <mert@futo.org>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://postgr.es/m/18964-ba09dea8c98fccd6%40postgresql.org
Backpatch-through: 15
A deadlock can occur when the DDL command and the apply worker acquire
catalog locks in different orders while dropping replication origins.
The issue is rare in PG16 and higher branches because, in most cases, the
tablesync worker performs the origin drop in those branches, and its
locking sequence does not conflict with DDL operations.
This patch ensures consistent lock acquisition to prevent such deadlocks.
As per buildfarm.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Ajin Cherian <itsajin@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 14, where it was introduced
Discussion: https://postgr.es/m/bab95e12-6cc5-4ebb-80a8-3e41956aa297@gmail.com
For many optional libraries, we extract the -L and -l switches needed
to link the library from a helper program such as llvm-config. In
some cases we put the resulting -L switches into LDFLAGS ahead of
-L switches specified via --with-libraries. That risks breaking
the user's intention for --with-libraries.
It's not such a problem if the library's -L switch points to a
directory containing only that library, but on some platforms a
library helper may "helpfully" offer a switch such as -L/usr/lib
that points to a directory holding all standard libraries. If the
user specified --with-libraries in hopes of overriding the standard
build of some library, the -L/usr/lib switch prevents that from
happening since it will come before the user-specified directory.
To fix, avoid inserting these switches directly into LDFLAGS during
configure, instead adding them to LIBDIRS or SHLIB_LINK. They will
still eventually get added to LDFLAGS, but only after the switches
coming from --with-libraries.
The same problem exists for -I switches: those coming from
--with-includes should appear before any coming from helper programs
such as llvm-config. We have not heard field complaints about this
case, but it seems certain that a user attempting to override a
standard library could have issues.
The changes for this go well beyond configure itself, however,
because many Makefiles have occasion to manipulate CPPFLAGS to
insert locally-desirable -I switches, and some of them got it wrong.
The correct ordering is any -I switches pointing at within-the-
source-tree-or-build-tree directories, then those from the tree-wide
CPPFLAGS, then those from helper programs. There were several places
that risked pulling in a system-supplied copy of libpq headers, for
example, instead of the in-tree files. (Commit cb36f8ec2 fixed one
instance of that a few months ago, but this exercise found more.)
The Meson build scripts may or may not have any comparable problems,
but I'll leave it to someone else to investigate that.
Reported-by: Charles Samborski <demurgos@demurgos.net>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/70f2155f-27ca-4534-b33d-7750e20633d7@demurgos.net
Backpatch-through: 13
When I prepared 71c0921b6 et al yesterday, I was thinking that the
logic involving explicitly freeing the node_list output was still
needed to dodge leakage bugs in libxml2. But I was misremembering:
we introduced that only because with early 2.13.x releases we could
not trust xmlParseBalancedChunkMemory's result code, so we had to
look to see if a node list was returned or not. There's no reason
to believe that xmlParseBalancedChunkMemory will fail to clean up
the node list when required, so simplify. (This essentially
completes reverting all the non-cosmetic changes in 6082b3d5d.)
Reported-by: Jim Jones <jim.jones@uni-muenster.de>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/997668.1753802857@sss.pgh.pa.us
Backpatch-through: 13
