The variables newestCommitTs and oldestCommitTs sound as if they are
timestamps, but in fact they are the transaction Ids that correspond
to the newest and oldest timestamps rather than the actual timestamps.
Rename these variables to reflect that they are actually xids: to wit
newestCommitTsXid and oldestCommitTsXid respectively. Also modify
related code in a similar fashion, particularly the user facing output
emitted by pg_controldata and pg_resetxlog.
Complaint and patch by me, review by Tom Lane and Alvaro Herrera.
Backpatch to 9.5 where these variables were first introduced.
Common mathematical convention is that exponentiation associates right to
left. We aren't going to change the parser for this, but we could note
it in the operator's description. (It's already noted in the operator
precedence/associativity table, but users might not look there.)
Per bug #13829 from Henrik Pauli.
Tone down an overly strong statement about which pseudo-types PLs are
likely to allow. Add "event_trigger" to the list, as well as
"pg_ddl_command" in 9.5/HEAD. Back-patch to 9.3 where event_trigger
was added.
For some reason, we've been overlooking the fact that pg_receivexlog
and pg_recvlogical are using wrong translation domains all along,
so their output hasn't ever been translated. The right domain is
pg_basebackup, not their own executable names.
Noticed by Ioseph Kim, who's been working on the Korean translation.
Backpatch pg_receivexlog to 9.2 and pg_recvlogical to 9.4.
Both Blowfish and DES implementations of crypt() can take arbitrarily
long time, depending on the number of rounds specified by the caller;
make sure they can be interrupted.
Author: Andreas Karlsson
Reviewer: Jeff Janes
Backpatch to 9.1.
brin_summarize_new_values() did not check that the passed OID was for
an index at all, much less that it was a BRIN index, and would fail in
obscure ways if it wasn't (possibly damaging data first?). It also
lacked any permissions test; by analogy to VACUUM, we should only allow
the table's owner to summarize.
Noted by Jeff Janes, fix by Michael Paquier and me
t/002_databases.pl was expecting to see a specific physical order of the
rows in pg_database. I broke that in HEAD with commit 01e386a325,
but I'd say it's a pretty fragile test methodology in any case, so fix
it in 9.5 as well.
This reverts most of commit 83dec5a71 in favor of having connectDatabase()
store the possibly-reusable password in a static variable, similar to the
coding we've had for a long time in pg_dump's version of that function.
To avoid possible problems with unwanted password reuse, make callers
specify whether it's reasonable to attempt to re-use the password.
This is a wash for cases where re-use isn't needed, but it is far simpler
for callers that do want that. Functionally there should be no difference.
Even though we're past RC1, it seems like a good idea to back-patch this
into 9.5, like the prior commit. Otherwise, if there are any third-party
users of connectDatabase(), they'll have to deal with an API change in
9.5 and then another one in 9.6.
Michael Paquier
When pg_dump prompts the user for a password, it remembers the password
for possible re-use by parallel worker processes. However, libpq might
have extracted the password from a connection string originally passed
as "dbname". Since we don't record the original form of dbname but
break it down to host/port/etc, the password gets lost. Fix that by
retrieving the actual password from the PGconn.
(It strikes me that this whole approach is rather broken, as it will also
lose other information such as options that might have been present in
the connection string. But we'll leave that problem for another day.)
In passing, get rid of rather silly use of malloc() for small fixed-size
arrays.
Back-patch to 9.3 where parallel pg_dump was introduced.
Report and fix by Zeus Kronion, adjusted a bit by Michael Paquier and me
Rather than expect the Query returned by get_view_query() to be
read-only and then copy bits and pieces of it out, simply copy the
entire structure when we get it. This addresses an issue where
AcquireRewriteLocks, which is called by acquireLocksOnSubLinks(),
scribbles on the parsetree passed in, which was actually an entry
in relcache, leading to segfaults with certain view definitions.
This also future-proofs us a bit for anyone adding more code to this
path.
The acquireLocksOnSubLinks() was added in commit c3e0ddd40.
Back-patch to 9.3 as that commit was.
psql offered USING, WHERE, and SET in this context, but SET is not a valid
possibility here. Seems to have been a thinko in commit f5ab0a14ea
which added DELETE's USING option.
Commit e5e11c8cc added a bunch of EXPLAIN statements without COSTS OFF
to the regression tests. This is contrary to project policy since it
results in unnecessary platform dependencies in the output (it's just
luck that we didn't get buildfarm failures from it). Per gripe from
Mike Wilson.
Previously the completion used the wrong word to match 'BY'. This was
introduced brokenly, in b2de2a. While at it, also add completion of
IN TABLESPACE ... OWNED BY and fix comments referencing nonexistent
syntax.
Reported-By: Michael Paquier
Author: Michael Paquier and Andres Freund
Discussion: CAB7nPqSHDdSwsJqX0d2XzjqOHr==HdWiubCi4L=Zs7YFTUne8w@mail.gmail.com
Backpatch: 9.4, like the commit introducing the bug
Per a recommendation from Tomas Vondra, it's more helpful to refer to
the value that determines how skewed a Gaussian or exponential
distribution is as a parameter rather than a threshold.
Since it's not quite too late to get this right in 9.5, where it was
introduced, back-patch this. Most of the patch changes only comments
and documentation, but a few pgbench messages are altered to match.
Fabien Coelho, reviewed by Michael Paquier and by me.
Turns out we must set rl_basic_word_break_characters *before* we call
rl_initialize() the first time, because it will quietly copy that value
elsewhere --- but only on the first call. (Love these undocumented
dependencies.) I broke this yesterday in commit 2ec477dc8108339d;
like that commit, back-patch to all active branches. Per report from
Pavel Stehule.
This is necessary so that REASSIGN OWNED does the right thing with
composite types, to wit, that it also alters ownership of the type's
pg_class entry -- previously, the pg_class entry remained owned by the
original user, which caused later other failures such as the new owner's
inability to use ALTER TYPE to rename an attribute of the affected
composite. Also, if the original owner is later dropped, the pg_class
entry becomes owned by a non-existant user which is bogus.
To fix, create a new routine AlterTypeOwner_oid which knows whether to
pass the request to ATExecChangeOwner or deal with it directly, and use
that in shdepReassignOwner rather than calling AlterTypeOwnerInternal
directly. AlterTypeOwnerInternal is now simpler in that it only
modifies the pg_type entry and recurses to handle a possible array type;
higher-level tasks are handled by either AlterTypeOwner directly or
AlterTypeOwner_oid.
I took the opportunity to add a few more objects to the test rig for
REASSIGN OWNED, so that more cases are exercised. Additional ones could
be added for superuser-only-ownable objects (such as FDWs and event
triggers) but I didn't want to push my luck by adding a new superuser to
the tests on a backpatchable bug fix.
Per bug #13666 reported by Chris Pacejo.
Backpatch to 9.5.
(I would back-patch this all the way back, except that it doesn't apply
cleanly in 9.4 and earlier because 59367fdf9 wasn't backpatched. If we
decide that we need this in earlier branches too, we should backpatch
both.)
It emerges that libreadline doesn't notice terminal window size change
events unless they occur while collecting input. This is easy to stumble
over if you resize the window while using a pager to look at query output,
but it can be demonstrated without any pager involvement. The symptom is
that queries exceeding one line are misdisplayed during subsequent input
cycles, because libreadline has the wrong idea of the screen dimensions.
The safest, simplest way to fix this is to call rl_reset_screen_size()
just before calling readline(). That causes an extra ioctl(TIOCGWINSZ)
for every command; but since it only happens when reading from a tty, the
performance impact should be negligible. A more valid objection is that
this still leaves a tiny window during entry to readline() wherein delivery
of SIGWINCH will be missed; but the practical consequences of that are
probably negligible. In any case, there doesn't seem to be any good way to
avoid the race, since readline exposes no functions that seem safe to call
from a generic signal handler --- rl_reset_screen_size() certainly isn't.
It turns out that we also need an explicit rl_initialize() call, else
rl_reset_screen_size() dumps core when called before the first readline()
call.
rl_reset_screen_size() is not present in old versions of libreadline,
so we need a configure test for that. (rl_initialize() is present at
least back to readline 4.0, so we won't bother with a test for it.)
We would need a configure test anyway since libedit's emulation of
libreadline doesn't currently include such a function. Fortunately,
libedit seems not to have any corresponding bug.
Merlin Moncure, adjusted a bit by me
Clarify that SELECT policies are now applied when SELECT rights
are required for a given query, even if the query is an UPDATE or
DELETE query. Pointed out by Noah.
Additionally, note the risk regarding concurrently open transactions
where a relation which controls access to the rows of another relation
are updated and the rows of the primary relation are also being
modified. Pointed out by Peter Geoghegan.
Back-patch to 9.5.
We carry around information about if a given query has row security or
not to allow the plancache to use that information to invalidate a
planned query in the event that the environment changes.
Previously, the flag of one of the subqueries was simply being copied
into place to indicate if the query overall included RLS components.
That's wrong as we need the global OR of all subqueries. Fix by
changing the code to match how fireRIRules works, which is results
in OR'ing all of the flags.
Noted by Tom.
Back-patch to 9.5 where RLS was introduced.
This previously resulted in an error and a nonzero exit status, but
after discussion this should rather be a noop with a zero exit status.
This is a back-patch of commit 6b34e55638,
plus two changes from commit e50cda7840
that teach pg_rewind to allow the initial control file states to be
DB_SHUTDOWNED_IN_RECOVERY as well as DB_SHUTDOWNED. That's necessary
to get the additional regression test case to pass, and the old behavior
seems like rather a foot-gun anyway.
Peter Eisentraut and Tom Lane
Apparently, there are bugs in this code that cause it to loop endlessly.
That bug still needs more research, but in the meantime it's clear that
the loop is missing a check for interrupts so that it can be cancelled
timely.
Backpatch to 9.1 -- this has been missing since 49475aab8d.
This one test was behaving differently between the ubuntu fix for
CVE-2015-7499 and the base "expected" file. It's not worth having
yet another version of the expected file for this test, so drop it.
Perhaps at some point when all distros have settled down to the
same behavior on this test, it can be restored.
Problem found by me on libxml2 (2.9.1+dfsg1-3ubuntu4.6).
Solution suggested by Tom Lane.
Backpatch to 9.5, where the test was added.
If libpq ran out of memory while constructing the result set, it would hang,
waiting for more data from the server, which might never arrive. To fix,
distinguish between out-of-memory error and not-enough-data cases, and give
a proper error message back to the client on OOM.
There are still similar issues in handling COPY start messages, but let's
handle that as a separate patch.
Michael Paquier, Amit Kapila and me. Backpatch to all supported versions.
Previously, if find_multixact_start() failed, SetOffsetVacuumLimit() would
install 0 into MultiXactState->offsetStopLimit if it previously succeeded.
Luckily, there are no known cases where find_multixact_start() will return
an error in 9.5 and above. But if it were to happen, for example due to
filesystem permission issues, it'd be somewhat bad: GetNewMultiXactId()
could continue allocating mxids even if close to a wraparound, or it could
erroneously stop allocating mxids, even if no wraparound is looming. The
wrong value would be corrected the next time SetOffsetVacuumLimit() is
called, or by a restart.
Reported-By: Noah Misch, although this is not his preferred fix
Discussion: 20151210140450.GA22278@alap3.anarazel.de
Backpatch: 9.5, where the bug was introduced as part of 4f627f
e3f4cfc7 introduced a LWLockHeldByMe() call, without the corresponding
Assert() surrounding it.
Spotted by Coverity.
Backpatch: 9.1+, like the previous commit
This has worked that way for a long time, maybe always, but you would
not have known it from the documentation. Also back-patch the notes
I added to HEAD earlier today about behavior of the "-f -" switch,
which likewise have been valid for many releases.
Previously the "sent" field would be set to 0 and all other xlog
pointers be set to NULL if there were no valid values (such as when
in a backup sending walsender).
These would leak random xlog positions if a walsender used for backup would
a walsender slot previously used by a replication walsender.
In passing also fix a couple of cases where the xlog pointer is directly
compared to zero instead of using XLogRecPtrIsInvalid, noted by
Michael Paquier.
Changing the tablespace of an unlogged relation did not WAL log the
creation and content of the init fork. Thus, after a standby is
promoted, unlogged relation cannot be accessed anymore, with errors
like:
ERROR: 58P01: could not open file "pg_tblspc/...": No such file or directory
Additionally the init fork was not synced to disk, independent of the
configured wal_level, a relatively small durability risk.
Investigation of that problem also brought to light that, even for
permanent relations, the creation of !main forks was not WAL logged,
i.e. no XLOG_SMGR_CREATE record were emitted. That mostly turns out not
to be a problem, because these files were created when the actual
relation data is copied; nonexistent files are not treated as an error
condition during replay. But that doesn't work for empty files, and
generally feels a bit haphazard. Luckily, outside init and main forks,
empty forks don't occur often or are not a problem.
Add the required WAL logging and syncing to disk.
Reported-By: Michael Paquier
Author: Michael Paquier and Andres Freund
Discussion: 20151210163230.GA11331@alap3.anarazel.de
Backpatch: 9.1, where unlogged relations were introduced
Recent releases of libxml2 do not provide error context reports for errors
detected at the very end of the input string. This appears to be a bug, or
at least an infelicity, introduced by the fix for libxml2's CVE-2015-7499.
We can hope that this behavioral change will get undone before too long;
but the security patch is likely to spread a lot faster/further than any
follow-on cleanup, which means this behavior is likely to be present in the
wild for some time to come. As a stopgap, add a variant regression test
expected-file that matches what you get with a libxml2 that acts this way.
As reported in bug #13809 by Alexander Ashurkov, the code for REASSIGN
OWNED hadn't gotten word about user mappings. Deal with them in the
same way default ACLs do, which is to ignore them altogether; they are
handled just fine by DROP OWNED. The other foreign object cases are
already handled correctly by both commands.
Also add a REASSIGN OWNED statement to foreign_data test to exercise the
foreign data objects. (The changes are just before the "cleanup" phase,
so it shouldn't remove any existing live test.)
Reported by Alexander Ashurkov, then independently by Jaime Casanova.
DROP OWNED BY handled GRANT-based ACLs but was not removing roles from
policies. Fix that by having DROP OWNED BY remove the role specified
from the list of roles the policy (or policies) apply to, or the entire
policy (or policies) if it only applied to the role specified.
As with ACLs, the DROP OWNED BY caller must have permission to modify
the policy or a WARNING is thrown and no change is made to the policy.
I originally modeled this data structure on SpecialJoinInfo, but after
commit acfcd45cac that looks like a pretty poor decision.
All we really need is relid sets identifying laterally-referenced rels;
and most of the time, what we want to know about includes indirect lateral
references, a case the LateralJoinInfo data was unsuited to compute with
any efficiency. The previous commit redefined RelOptInfo.lateral_relids
as the transitive closure of lateral references, so that it easily supports
checking indirect references. For the places where we really do want just
direct references, add a new RelOptInfo field direct_lateral_relids, which
is easily set up as a copy of lateral_relids before we perform the
transitive closure calculation. Then we can just drop lateral_info_list
and LateralJoinInfo and the supporting code. This makes the planner's
handling of lateral references noticeably more efficient, and shorter too.
Such a change can't be back-patched into stable branches for fear of
breaking extensions that might be looking at the planner's data structures;
but it seems not too late to push it into 9.5, so I've done so.
ALTER POLICY hadn't fully considered partial policy alternation
(eg: change just the roles on the policy, or just change one of
the expressions) when rebuilding the dependencies. Instead, it
would happily remove all dependencies which existed for the
policy and then only recreate the dependencies for the objects
referred to in the specific ALTER POLICY command.
Correct that by extracting and building the dependencies for all
objects referenced by the policy, regardless of if they were
provided as part of the ALTER POLICY command or were already in
place as part of the pre-existing policy.
More fuzz testing by Andreas Seltenreich exposed that the planner did not
cope well with chains of lateral references. If relation X references Y
laterally, and Y references Z laterally, then we will have to scan X on the
inside of a nestloop with Z, so for all intents and purposes X is laterally
dependent on Z too. The planner did not understand this and would generate
intermediate joins that could not be used. While that was usually harmless
except for wasting some planning cycles, under the right circumstances it
would lead to "failed to build any N-way joins" or "could not devise a
query plan" planner failures.
To fix that, convert the existing per-relation lateral_relids and
lateral_referencers relid sets into their transitive closures; that is,
they now show all relations on which a rel is directly or indirectly
laterally dependent. This not only fixes the chained-reference problem
but allows some of the relevant tests to be made substantially simpler
and faster, since they can be reduced to simple bitmap manipulations
instead of searches of the LateralJoinInfo list.
Also, when a PlaceHolderVar that is due to be evaluated at a join contains
lateral references, we should treat those references as indirect lateral
dependencies of each of the join's base relations. This prevents us from
trying to join any individual base relations to the lateral reference
source before the join is formed, which again cannot work.
Andreas' testing also exposed another oversight in the "dangerous
PlaceHolderVar" test added in commit 85e5e222b1. Simply rejecting
unsafe join paths in joinpath.c is insufficient, because in some cases
we will end up rejecting *all* possible paths for a particular join, again
leading to "could not devise a query plan" failures. The restriction has
to be known also to join_is_legal and its cohort functions, so that they
will not select a join for which that will happen. I chose to move the
supporting logic into joinrels.c where the latter functions are.
Back-patch to 9.3 where LATERAL support was introduced.
This module needs explicit initialization in order to replay WAL records
in recovery, but we had broken this recently following changes to make
other (stranger) scenarios work correctly. To fix, rework the
initialization sequence so that it always takes place before WAL replay
commences for both master and standby.
I could have gone for a more localized fix that just added a "startup"
call for the master server, but it seemed better to restructure the
existing callers as well so that the whole thing made more sense. As a
drawback, there is more control logic in xlog.c now than previously, but
doing otherwise meant passing down the ControlFile flag, which seemed
uglier as a whole.
This also meant adding a check to not re-execute ActivateCommitTs if it
had already been called.
Reported by Fujii Masao.
Backpatch to 9.5.
