Roles with MAINTAIN on a relation may run VACUUM, ANALYZE, REINDEX,
REFRESH MATERIALIZE VIEW, CLUSTER, and LOCK TABLE on the relation.
Roles with privileges of pg_maintain may run those same commands on
all relations.
This was previously committed for v16, but it was reverted in
commit 151c22deee due to concerns about search_path tricks that
could be used to escalate privileges to the table owner. Commits
2af07e2f74, 59825d1639, and c7ea3f4229 resolved these concerns by
restricting search_path when running maintenance commands.
Bumps catversion.
Reviewed-by: Jeff Davis
Discussion: https://postgr.es/m/20240305161235.GA3478007%40nathanxps13
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
ff9618e82a introduced has_partition_ancestor_privs(), which is used
to check whether a user has MAINTAIN on any partition ancestors.
This involves syscache lookups, and presently this function does
not take any relation locks, so it is likely subject to the same
kind of cache lookup failures that were fixed by 19de0ab23c.
To fix this problem, this commit partially reverts ff9618e82a.
Specifically, it removes the partition-related changes, including
the has_partition_ancestor_privs() function mentioned above. This
means that MAINTAIN on a partitioned table is no longer sufficient
to perform maintenance commands on its partitions. This is more
like how privileges for maintenance commands work on supported
versions. Privileges are checked for each partition, so a command
that flows down to all partitions might refuse to process them
(e.g., if the current user doesn't have MAINTAIN on the partition).
In passing, adjust a few related comments and error messages, and
add a test for the privilege checks for CLUSTER on a partitioned
table.
Reviewed-by: Michael Paquier, Jeff Davis
Discussion: https://postgr.es/m/20230613211246.GA219055%40nathanxps13
The rule system needs "old" and/or "new" pseudo-RTEs in rule actions
that are ON INSERT/UPDATE/DELETE. Historically it's put such entries
into the ON SELECT rules of views as well, but those are really quite
vestigial. The only thing we've used them for is to carry the
view's relid forward to AcquireExecutorLocks (so that we can
re-lock the view to verify it hasn't changed before re-using a plan)
and to carry its relid and permissions data forward to execution-time
permissions checks. What we can do instead of that is to retain
these fields of the RTE_RELATION RTE for the view even after we
convert it to an RTE_SUBQUERY RTE. This requires a tiny amount of
extra complication in the planner and AcquireExecutorLocks, but on
the other hand we can get rid of the logic that moves that data from
one place to another.
The principal immediate benefit of doing this, aside from a small
saving in the pg_rewrite data for views, is that these pseudo-RTEs
no longer trigger ruleutils.c's heuristic about qualifying variable
names when the rangetable's length is more than 1. That results
in quite a number of small simplifications in regression test outputs,
which are all to the good IMO.
Bump catversion because we need to dump a few more fields of
RTE_SUBQUERY RTEs. While those will always be zeroes anyway in
stored rules (because we'd never populate them until query rewrite)
they are useful for debugging, and it seems like we'd better make
sure to transmit such RTEs accurately in plans sent to parallel
workers. I don't think the executor actually examines these fields
after startup, but someday it might.
This is a second attempt at committing 1b4d280ea. The difference
from the first time is that now we can add some filtering rules to
AdjustUpgrade.pm to allow cross-version upgrade testing to pass
despite all the cosmetic changes in CREATE VIEW outputs.
Amit Langote (filtering rules by me)
Discussion: https://postgr.es/m/CA+HiwqEf7gPN4Hn+LoZ4tP2q_Qt7n3vw7-6fJKOf92tSEnX6Gg@mail.gmail.com
Discussion: https://postgr.es/m/891521.1673657296@sss.pgh.pa.us
Commit 60684dd8 left loose ends when it came to maintaining toast
tables or partitions.
For toast tables, simply skip the privilege check if the toast table
is an indirect target of the maintenance command, because the main
table privileges have already been checked.
For partitions, allow the maintenance command if the user has the
MAINTAIN privilege on the partition or any parent.
Also make CLUSTER emit "skipping" messages when the user doesn't have
privileges, similar to VACUUM.
Author: Nathan Bossart
Reported-by: Pavel Luzanov
Reviewed-by: Pavel Luzanov, Ted Yu
Discussion: https://postgr.es/m/20230113231339.GA2422750@nathanxps13
The prior behavior was confusing and hard to document. For instance,
if you had UPDATE privileges, you could lock a table in any lock mode
except ACCESS SHARE mode.
Now, if granted a privilege to lock at a given mode, one also has
privileges to lock at a less-conflicting mode. MAINTAIN, UPDATE,
DELETE, and TRUNCATE privileges allow any lock mode. INSERT privileges
allow ROW EXCLUSIVE (or below). SELECT privileges allow ACCESS SHARE.
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/9550c76535404a83156252b25a11babb4792ea1e.camel%40j-davis.com
This reverts commit 1b4d280ea1.
It's broken the buildfarm members that run cross-version-upgrade tests,
because they're not prepared to deal with cosmetic differences between
CREATE VIEW commands emitted by older servers and HEAD. Even if we had
a solution to that, which we don't, it'd take some time to roll it out
to the affected animals. This improvement isn't valuable enough to
justify addressing that problem on an emergency basis, so revert it
for now.
The rule system needs "old" and/or "new" pseudo-RTEs in rule actions
that are ON INSERT/UPDATE/DELETE. Historically it's put such entries
into the ON SELECT rules of views as well, but those are really quite
vestigial. The only thing we've used them for is to carry the
view's relid forward to AcquireExecutorLocks (so that we can
re-lock the view to verify it hasn't changed before re-using a plan)
and to carry its relid and permissions data forward to execution-time
permissions checks. What we can do instead of that is to retain
these fields of the RTE_RELATION RTE for the view even after we
convert it to an RTE_SUBQUERY RTE. This requires a tiny amount of
extra complication in the planner and AcquireExecutorLocks, but on
the other hand we can get rid of the logic that moves that data from
one place to another.
The principal immediate benefit of doing this, aside from a small
saving in the pg_rewrite data for views, is that these pseudo-RTEs
no longer trigger ruleutils.c's heuristic about qualifying variable
names when the rangetable's length is more than 1. That results
in quite a number of small simplifications in regression test outputs,
which are all to the good IMO.
Bump catversion because we need to dump a few more fields of
RTE_SUBQUERY RTEs. While those will always be zeroes anyway in
stored rules (because we'd never populate them until query rewrite)
they are useful for debugging, and it seems like we'd better make
sure to transmit such RTEs accurately in plans sent to parallel
workers. I don't think the executor actually examines these fields
after startup, but someday it might.
Amit Langote
Discussion: https://postgr.es/m/CA+HiwqEf7gPN4Hn+LoZ4tP2q_Qt7n3vw7-6fJKOf92tSEnX6Gg@mail.gmail.com
Make sure that function declarations use names that exactly match the
corresponding names from function definitions in optimizer, parser,
utility, libpq, and "commands" code, as well as in remaining library
code. Do the same for all code related to frontend programs (with the
exception of pg_dump/pg_dumpall related code).
Like other recent commits that cleaned up function parameter names, this
commit was written with help from clang-tidy. Later commits will handle
ecpg and pg_dump/pg_dumpall.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
A security invoker view checks permissions for accessing its
underlying base relations using the privileges of the user of the
view, rather than the privileges of the view owner. Additionally, if
any of the base relations are tables with RLS enabled, the policies of
the user of the view are applied, rather than those of the view owner.
This allows views to be defined without giving away additional
privileges on the underlying base relations, and matches a similar
feature available in other database systems.
It also allows views to operate more naturally with RLS, without
affecting the assignments of policies to users.
Christoph Heiss, with some additional hacking by me. Reviewed by
Laurenz Albe and Wolfgang Walther.
Discussion: https://postgr.es/m/b66dd6d6-ad3e-c6f2-8b90-47be773da240%40cybertec.at
Most error messages about a relkind that was not supported or
appropriate for the command was of the pattern
"relation \"%s\" is not a table, foreign table, or materialized view"
This style can become verbose and tedious to maintain. Moreover, it's
not very helpful: If I'm trying to create a comment on a TOAST table,
which is not supported, then the information that I could have created
a comment on a materialized view is pointless.
Instead, write the primary error message shorter and saying more
directly that what was attempted is not possible. Then, in the detail
message, explain that the operation is not supported for the relkind
the object was. To simplify that, add a new function
errdetail_relkind_not_supported() that does this.
In passing, make use of RELKIND_HAS_STORAGE() where appropriate,
instead of listing out the relkinds individually.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/flat/dc35a398-37d0-75ce-07ea-1dd71d98f8ec@2ndquadrant.com
Two cases violated list APIs by throwing away the return value. While
the code was technically correct, it relied on internal knowledge of
the list implementation, and the code wasn't really gaining anything
that way. It is planned to make this a compiler warning in the
future, so just fix these cases by assigning the return value
properly.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/e3753562-99cd-b65f-5aca-687dfd1ec2fc@2ndquadrant.com
Revert 59ab4ac32, as well as the followup fix 33862cb9c, in all
branches. We need to think a bit harder about what the behavior
of LOCK TABLE on views should be, and there's no time for that
before next week's releases. We'll take another crack at this
later.
Discussion: https://postgr.es/m/16703-e348f58aab3cf6cc@postgresql.org
LOCK TABLE has complained about "infinite recursion" when applied
to a self-referential view, ever since we made it recurse into views
in v11. However, that breaks pg_dump's new assumption that it's
okay to lock every relation. There doesn't seem to be any good
reason to throw an error: if we just abandon the recursion, we've
still satisfied the requirement of locking every referenced relation.
Per bug #16703 from Andrew Bille (via Alexander Lakhin).
Discussion: https://postgr.es/m/16703-e348f58aab3cf6cc@postgresql.org
The restriction that only tables and views can be locked by LOCK TABLE
is quite arbitrary, since the underlying mechanism can lock any relation
type. Drop the restriction so that programs such as pg_dump can lock
all relations they're interested in, preventing schema changes that
could cause a dump to fail after expending much effort.
Backpatch to 9.5.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Wells Oliver <wells.oliver@gmail.com>
Discussion: https://postgr.es/m/20201021200659.GA32358@alvherre.pgsql
Previously, LOCK TABLE command through a parent table checked
the permissions on not only the parent table but also the children
tables inherited from it. This was a bug and inherited queries should
perform access permission checks on the parent table only. This
commit fixes LOCK TABLE so that it does not check the permission
on children tables.
This patch is applied only in the master branch. We decided not to
back-patch because it's not hard to imagine that there are some
applications expecting the old behavior and the change breaks their
security.
Author: Amit Langote
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/CAHGQGwE+GauyG7POtRfRwwthAGwTjPQYdFHR97+LzA4RHGnJxA@mail.gmail.com
Previously, check_xact_readonly() was responsible for determining
which types of queries could not be run in a read-only transaction,
standard_ProcessUtility() was responsibility for prohibiting things
which were allowed in read only transactions but not in recovery, and
utility commands were basically prohibited in bulk in parallel mode by
calls to CommandIsReadOnly() in functions.c and spi.c. This situation
was confusing and error-prone. Accordingly, move all the checks to a
new function ClassifyUtilityCommandAsReadOnly(), which determines the
degree to which a given statement is read only.
In the old code, check_xact_readonly() inadvertently failed to handle
several statement types that actually should have been prohibited,
specifically T_CreatePolicyStmt, T_AlterPolicyStmt, T_CreateAmStmt,
T_CreateStatsStmt, T_AlterStatsStmt, and T_AlterCollationStmt. As a
result, thes statements were erroneously allowed in read only
transactions, parallel queries, and standby operation. Generally, they
would fail anyway due to some lower-level error check, but we
shouldn't rely on that. In the new code structure, future omissions
of this type should cause ClassifyUtilityCommandAsReadOnly() to
complain about an unrecognized node type.
As a fringe benefit, this means we can allow certain types of utility
commands in parallel mode, where it's safe to do so. This allows
ALTER SYSTEM, CALL, DO, CHECKPOINT, COPY FROM, EXPLAIN, and SHOW.
It might be possible to allow additional commands with more work
and thought.
Along the way, document the thinking process behind the current set
of checks, as per discussion especially with Peter Eisentraut. There
is some interest in revising some of these rules, but that seems
like a job for another patch.
Patch by me, reviewed by Tom Lane, Stephen Frost, and Peter
Eisentraut.
Discussion: http://postgr.es/m/CA+TgmoZ_rLqJt5sYkvh+JpQnfX0Y+B2R+qfi820xNih6x-FQOQ@mail.gmail.com
Formerly, lcons was about the same speed as lappend, but with the new
List implementation, that's not so; with a long List, data movement
imposes an O(N) cost on lcons and list_delete_first, but not lappend.
Hence, invent list_delete_last with semantics parallel to
list_delete_first (but O(1) cost), and change various places to use
lappend and list_delete_last where this can be done without much
violence to the code logic.
There are quite a few places that construct result lists using lcons not
lappend. Some have semantic rationales for that; I added comments about
it to a couple that didn't have them already. In many such places though,
I think the coding is that way only because back in the dark ages lcons
was faster than lappend. Hence, switch to lappend where this can be done
without causing semantic changes.
In ExecInitExprRec(), this results in aggregates and window functions that
are in the same plan node being executed in a different order than before.
Generally, the executions of such functions ought to be independent of
each other, so this shouldn't result in visibly different query results.
But if you push it, as one regression test case does, you can show that
the order is different. The new order seems saner; it's closer to
the order of the functions in the query text. And we never documented
or promised anything about this, anyway.
Also, in gistfinishsplit(), don't bother building a reverse-order list;
it's easy now to iterate backwards through the original list.
It'd be possible to go further towards removing uses of lcons and
list_delete_first, but it'd require more extensive logic changes,
and I'm not convinced it's worth it. Most of the remaining uses
deal with queues that probably never get long enough to be worth
sweating over. (Actually, I doubt that any of the changes in this
patch will have measurable performance effects either. But better
to have good examples than bad ones in the code base.)
Patch by me, thanks to David Rowley and Daniel Gustafsson for review.
Discussion: https://postgr.es/m/21272.1563318411@sss.pgh.pa.us
Such calls can confuse the reader as strcmp() uses an integer as result.
The places patched here have been spotted by Thomas Munro, David Rowley
and myself.
Author: Michael Paquier
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/20190411021946.GG2728@paquier.xyz
There were two flags used to track the access to temporary tables and
to the temporary namespace of a session which are used to restrict
PREPARE TRANSACTION, however the first control flag is a concept
included in the second. This removes the flag for temporary table
tracking, keeping around only the one at namespace level.
Author: Michael Paquier
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/20190118053126.GH1883@paquier.xyz
Attempting to use a temporary table within a two-phase transaction is
forbidden for ages. However, there have been uncovered grounds for
a couple of other object types and commands which work on temporary
objects with two-phase commit. In short, trying to create, lock or drop
an object on a temporary schema should not be authorized within a
two-phase transaction, as it would cause its state to create
dependencies with other sessions, causing all sorts of side effects with
the existing session or other sessions spawned later on trying to use
the same temporary schema name.
Regression tests are added to cover all the grounds found, the original
report mentioned function creation, but monitoring closer there are many
other patterns with LOCK, DROP or CREATE EXTENSION which are involved.
One of the symptoms resulting in combining both is that the session
which used the temporary schema is not able to shut down completely,
waiting for being able to drop the temporary schema, something that it
cannot complete because of the two-phase transaction involved with
temporary objects. In this case the client is able to disconnect but
the session remains alive on the backend-side, potentially blocking
connection backend slots from being used. Other problems reported could
also involve server crashes.
This is back-patched down to v10, which is where 9b013dc has introduced
MyXactFlags, something that this patch relies on.
Reported-by: Alexey Bashtanov
Author: Michael Paquier
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/5d910e2e-0db8-ec06-dd5f-baec420513c3@imap.cc
Backpatch-through: 10
Traditionally, include/catalog/pg_foo.h contains extern declarations
for functions in backend/catalog/pg_foo.c, in addition to its function
as the authoritative definition of the pg_foo catalog's rowtype.
In some cases, we'd been forced to split out those extern declarations
into separate pg_foo_fn.h headers so that the catalog definitions
could be #include'd by frontend code. That problem is gone as of
commit 9c0a0de4c, so let's undo the splits to make things less
confusing.
Discussion: https://postgr.es/m/23690.1523031777@sss.pgh.pa.us
LockViewRecurese() obtains view relation using heap_open() and passes
it to get_view_query() to get view info. It immediately closes the
relation then uses the returned view info by calling
LockViewRecurse_walker(). Since get_view_query() returns a pointer
within the relcache, the relcache should be kept until
LockViewRecurse_walker() returns. Otherwise the relation could point
to a garbage memory area.
Fix is moving the heap_close() call after LockViewRecurse_walker().
Problem reported by Tom Lane (buildfarm is unhappy, especially prion
since it enables -DRELCACHE_FORCE_RELEASE cpp flag), fix by me.
A followup patch will add a SKIP_LOCKED option. To avoid introducing
evermore arguments, breaking existing callers each time, introduce a
flags argument. This'll no doubt break a few external users...
Also change the MISSING_OK behaviour so a DEBUG1 debug message is
emitted when a relation is not found.
Author: Nathan Bossart
Reviewed-By: Michael Paquier and Andres Freund
Discussion: https://postgr.es/m/20180306005349.b65whmvj7z6hbe2y@alap3.anarazel.de
AclObjectKind was basically just another enumeration for object types,
and we already have a preferred one for that. It's only used in
aclcheck_error. By using ObjectType instead, we can also give some more
precise error messages, for example "index" instead of "relation".
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
Now that it has only INH_NO and INH_YES values, it's just weird that
it's not a plain bool, so make it that way.
Also rename RangeVar.inhOpt to "inh", to be like RangeTblEntry.inh.
My recollection is that we gave it a different name specifically because
it had a different representation than the derived bool value, but it
no longer does. And this is a good forcing function to be sure we
catch any places that are affected by the change.
Bump catversion because of possible effect on stored RangeVar nodes.
I'm not exactly convinced that we ever store RangeVar on disk, but
we have a readfuncs function for it, so be cautious. (If we do do so,
then commit e13486eba was in error not to bump catversion.)
Follow-on to commit e13486eba.
Discussion: http://postgr.es/m/CA+TgmoYe+EG7LdYX6pkcNxr4ygkP4+A=jm9o-CPXyOvRiCNwaQ@mail.gmail.com
Table partitioning is like table inheritance and reuses much of the
existing infrastructure, but there are some important differences.
The parent is called a partitioned table and is always empty; it may
not have indexes or non-inherited constraints, since those make no
sense for a relation with no data of its own. The children are called
partitions and contain all of the actual data. Each partition has an
implicit partitioning constraint. Multiple inheritance is not
allowed, and partitioning and inheritance can't be mixed. Partitions
can't have extra columns and may not allow nulls unless the parent
does. Tuples inserted into the parent are automatically routed to the
correct partition, so tuple-routing ON INSERT triggers are not needed.
Tuple routing isn't yet supported for partitions which are foreign
tables, and it doesn't handle updates that cross partition boundaries.
Currently, tables can be range-partitioned or list-partitioned. List
partitioning is limited to a single column, but range partitioning can
involve multiple columns. A partitioning "column" can be an
expression.
Because table partitioning is less general than table inheritance, it
is hoped that it will be easier to reason about properties of
partitions, and therefore that this will serve as a better foundation
for a variety of possible optimizations, including query planner
optimizations. The tuple routing based which this patch does based on
the implicit partitioning constraints is an example of this, but it
seems likely that many other useful optimizations are also possible.
Amit Langote, reviewed and tested by Robert Haas, Ashutosh Bapat,
Amit Kapila, Rajkumar Raghuwanshi, Corey Huinker, Jaime Casanova,
Rushabh Lathia, Erik Rijkers, among others. Minor revisions by me.
INSERT acquires RowExclusiveLock during normal operation and therefore
it makes sense to allow LOCK TABLE .. ROW EXCLUSIVE MODE to be executed
by users who have INSERT rights on a table (even if they don't have
UPDATE or DELETE).
Not back-patching this as it's a behavior change which, strictly
speaking, loosens security restrictions.
Per discussion with Tom and Robert (circa 2013).
Nathan Bossart
Peter Eisentraut
Bruce Momjian
Tom Lane
Jeff Davis
Peter Geoghegan
Dean Rasheed
Alvaro Herrera
Fujii Masao
Robert Haas
Amit Kapila
Michael Paquier
Andres Freund
Tatsuo Ishii
Peter Eisentraut
Heikki Linnakangas
Stephen Frost