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
Macros like VARDATA() and VARSIZE() should be thought of as taking
values of type pointer to struct varlena or some other related struct.
The way they are implemented, you can pass anything to it and it will
cast it right. But this is in principle incorrect. To fix, add the
required DatumGetPointer() calls. Or in a couple of cases, remove
superfluous PointerGetDatum() calls.
It is planned in a subsequent patch to change macros like VARDATA()
and VARSIZE() to inline functions, which will enforce stricter typing.
This is in preparation for that.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/928ea48f-77c6-417b-897c-621ef16685a6%40eisentraut.org
For import and export, use schemaname/relname rather than
regclass.
This is more natural during export, fits with the other arguments
better, and it gives better control over error handling in case we
need to downgrade more errors to warnings.
Also, use text for the argument types for schemaname, relname, and
attname so that casts to "name" are not required.
Author: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/CADkLM=ceOSsx_=oe73QQ-BxUFR2Cwqum7-UP_fPe22DBY0NerA@mail.gmail.com
Add relallfrozen, an estimate of the number of pages marked all-frozen
in the visibility map.
pg_class already has relallvisible, an estimate of the number of pages
in the relation marked all-visible in the visibility map. This is used
primarily for planning.
relallfrozen, together with relallvisible, is useful for estimating the
outstanding number of all-visible but not all-frozen pages in the
relation for the purposes of scheduling manual VACUUMs and tuning vacuum
freeze parameters.
A future commit will use relallfrozen to trigger more frequent vacuums
on insert-focused workloads with significant volume of frozen data.
Bump catalog version
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_aj-P7YyBz_cPNwztz6ohP%2BvWis%3Diz3YcomkB3NpYA--w%40mail.gmail.com
Previously we used attname for both table and index columns, but
that is problematic for indexes because their attnames are assigned
by internal rules that don't guarantee to preserve the names across
dump and reload. (This is what's causing the remaining buildfarm
failures in cross-version-upgrade tests.) Fortunately we can use
attnum instead, since there's no such thing as adding or dropping
columns in an existing index. We met this same problem previously
with ALTER INDEX ... SET STATISTICS, and solved it the same way,
cf commit 5b6d13eec.
In pg_restore_attribute_stats() itself, we accept either attnum or
attname, but the policy used by pg_dump is to always use attname
for tables and attnum for indexes.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Author: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/1457469.1740419458@sss.pgh.pa.us
After commit f3dae2ae58, the primary purpose of separating the
pg_set_*_stats() from the pg_restore_*_stats() variants was
eliminated.
Leave pg_restore_relation_stats() and pg_restore_attribute_stats(),
which satisfy both purposes, and remove pg_set_relation_stats() and
pg_set_attribute_stats().
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/1457469.1740419458@sss.pgh.pa.us
Although they're exposed as int4 in pg_class, relpages and
relallvisible are really of type BlockNumber, that is uint32.
Correct type puns in relation_statistics_update() and remove
inappropriate range-checks. The type puns are only cosmetic
issues, but the range checks would cause failures with huge
relations.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/614341.1740269035@sss.pgh.pa.us
Follow locking behavior of ANALYZE when importing statistics. In
particular, when importing index statistics, the table must be locked
in ShareUpdateExclusive mode. Fixes bug reportd by Jian He.
ANALYZE doesn't update statistics on partitioned indexes, and the
locking requirements are slightly different for in-place updates on
partitioned indexes versus normal indexes. To be conservative, lock
both the partitioned table and the partitioned index in
ShareUpdateExclusive mode when importing stats for a partitioned
index.
Author: Corey Huinker
Reported-by: Jian He
Reviewed-by: Michael Paquier
Discussion: https://www.postgresql.org/message-id/CACJufxGreTY7qsCV8%2BBkuv0p5SXGTScgh%3DD%2BDq6%3D%2B_%3DXTp7FWg%40mail.gmail.com
The parameter 'rel' in lookup_var_attr_stats was once used to draw an
ERROR when ANALYZE failed to acquire sufficient data to build extended
statistics. bf2a691e0 changed the logic to raise a WARNING in the
caller instead. As a result, this parameter is no longer needed and
can be removed. Since this is a static function, we can always easily
reintroduce the parameter if it's ever needed in the future.
Author: Ilia Evdokimov
Reviewed-by: Fabrízio de Royes Mello
Discussion: https://postgr.es/m/b3880f22-5808-4206-88d4-1553a81c3440@tantorlabs.com
Previously, database object statistics manipulation functions like
pg_set_relation_stats() reported unclear error and hint messages
when executed during recovery. These messages were "internal",
making it difficult for users to understand the issue:
ERROR: cannot acquire lock mode ShareUpdateExclusiveLock on database objects while recovery is in progress
HINT: Only RowExclusiveLock or less can be acquired on database objects during recovery.
This commit updates the error handling so that, if these functions
are called during recovery, they produce clearer messages:
ERROR: recovery is in progress
HINT: Statistics cannot be modified during recovery.
The related documentation has also been updated to explicitly
clarify that these functions are not available during recovery.
Author: Fujii Masao
Reviewed-by: Heikki Linnakangas, Maxim Orlov
Discussion: https://postgr.es/m/6d313829-5f56-4a28-ae4b-bd01bf1ae791@oss.nttdata.com
Similar to the pg_set_*_stats() functions, except with a variadic
signature that's designed to be more future-proof. Additionally, most
problems are reported as WARNINGs rather than ERRORs, allowing most
stats to be restored even if some cannot.
These functions are intended to be called from pg_dump to avoid the
need to run ANALYZE after an upgrade.
Author: Corey Huinker
Discussion: https://postgr.es/m/CADkLM=eErgzn7ECDpwFcptJKOk9SxZEk5Pot4d94eVTZsvj3gw@mail.gmail.com
Some buildfarm members complained about an always-true test in the
SOFT_ERROR_OCCURRED macro. Fix by reading the field directly rather
than using the macro.
Reported-by: Tom Lane
Discussion: https://postgr.es/m/2144895.1729653514@sss.pgh.pa.us
Enable manipulation of attribute statistics. Only superficial
validation is performed, so it's possible to add nonsense, and it's up
to the planner (or other users of statistics) to behave reasonably in
that case.
Bump catalog version.
Author: Corey Huinker
Discussion: https://postgr.es/m/CADkLM=eErgzn7ECDpwFcptJKOk9SxZEk5Pot4d94eVTZsvj3gw@mail.gmail.com
The error message(s) were reporting the stats kind of 'f', which is not
correct as that's for the "dependencies" statistics kind.
Reported-by: Horst Reiterer
Reviewed-by: Richard Guo
Discussion: https://postgr.es/m/18375-ba99383eb9062d6a@postgresql.org
Backpatch-through: 12, where MCV extended stats were added.
as determined by include-what-you-use (IWYU)
While IWYU also suggests to *add* a bunch of #include's (which is its
main purpose), this patch does not do that. In some cases, a more
specific #include replaces another less specific one.
Some manual adjustments of the automatic result:
- IWYU currently doesn't know about includes that provide global
variable declarations (like -Wmissing-variable-declarations), so
those includes are being kept manually.
- All includes for port(ability) headers are being kept for now, to
play it safe.
- No changes of catalog/pg_foo.h to catalog/pg_foo_d.h, to keep the
patch from exploding in size.
Note that this patch touches just *.c files, so nothing declared in
header files changes in hidden ways.
As a small example, in src/backend/access/transam/rmgr.c, some IWYU
pragma annotations are added to handle a special case there.
Discussion: https://www.postgresql.org/message-id/flat/af837490-6b2f-46df-ba05-37ea6a6653fc%40eisentraut.org
Remove IsBackgroundWorker, IsAutoVacuumLauncherProcess(),
IsAutoVacuumWorkerProcess(), and IsLogicalSlotSyncWorker() in favor of
new Am*Process() macros that use MyBackendType. For consistency with
the existing Am*Process() macros.
Reviewed-by: Andres Freund
Discussion: https://www.postgresql.org/message-id/f3ecd4cb-85ee-4e54-8278-5fabfb3a4ed0@iki.fi
As of commit eaa5808e8e, MemoryContextResetAndDeleteChildren() is
just a backwards compatibility macro for MemoryContextReset(). Now
that some time has passed, this macro seems more likely to create
confusion.
This commit removes the macro and replaces all remaining uses with
calls to MemoryContextReset(). Any third-party code that use this
macro will need to be adjusted to call MemoryContextReset()
instead. Since the two have behaved the same way since v9.5, such
adjustments won't produce any behavior changes for all
currently-supported versions of PostgreSQL.
Reviewed-by: Amul Sul, Tom Lane, Alvaro Herrera, Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/20231113185950.GA1668018%40nathanxps13
The VacAttrStats structure contained the whole Form_pg_attribute for a
column, but it actually only needs attstattarget from there. So
remove the Form_pg_attribute field and make a separate field for
attstattarget. This simplifies some code for extended statistics that
doesn't deal with a column but an expression, which had to fake up
pg_attribute rows to satisfy internal APIs. Also, we can remove some
comments that essentially said "don't look at pg_attribute directly".
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/d6069765-5971-04d3-c10d-e4f7b2e9c459%40eisentraut.org
Run pgindent, pgperltidy, and reformat-dat-files.
This set of diffs is a bit larger than typical. We've updated to
pg_bsd_indent 2.1.2, which properly indents variable declarations that
have multi-line initialization expressions (the continuation lines are
now indented one tab stop). We've also updated to perltidy version
20230309 and changed some of its settings, which reduces its desire to
add whitespace to lines to make assignments etc. line up. Going
forward, that should make for fewer random-seeming changes to existing
code.
Discussion: https://postgr.es/m/20230428092545.qfb3y5wcu4cm75ur@alvherre.pgsql
When extracting an attr from a cached tuple in the syscache with
SysCacheGetAttr the isnull parameter must be checked in case the
attr cannot be NULL. For cases when this is known beforehand, a
wrapper is introduced which perform the errorhandling internally
on behalf of the caller, invoking an elog in case of a NULL attr.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/AD76405E-DB45-46B6-941F-17B1EB3A9076@yesql.se
Scanning the expression for compatible Vars isn't really necessary,
because the subsequent match against StatisticExtInfo entries will
eliminate expressions containing other Vars just fine. Moreover,
this code hadn't stopped to think about what to do with
PlaceHolderVars or Aggrefs in the clause; and at least for the PHV
case, that demonstrably leads to failures. Rather than work out
whether it's reasonable to ignore those, let's just remove the
whole stanza.
Per report from Richard Guo. Back-patch to v14 where this code
was added.
Discussion: https://postgr.es/m/CAMbWs48Mmvm-acGevXuwpB=g5JMqVSL6i9z5UaJyLGJqa-XPAA@mail.gmail.com
A future commit will move the checkAsUser field from RangeTblEntry
to a new node that, unlike RTEs, will only be created for tables
mentioned in the query but not for the inheritance child relations
added to the query by the planner. So, checkAsUser value for a
given child relation will have to be obtained by referring to that
for its ancestor mentioned in the query.
In preparation, it seems better to expand the use of RelOptInfo.userid
during planning in place of rte->checkAsUser so that there will be
fewer places to adjust for the above change.
Given that the child-to-ancestor mapping is not available during the
execution of a given "child" ForeignScan node, add a checkAsUser
field to ForeignScan to carry the child relation's RelOptInfo.userid.
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqGFCs2uq7VRKi7g+FFKbP6Ea_2_HkgZb2HPhUfaAKT3ng@mail.gmail.com
