If we have a local Var of say varchar type with default collation, and
we apply a RelabelType to convert that to text with default collation, we
don't want to consider that as creating an FDW_COLLATE_UNSAFE situation.
It should be okay to compare that to a remote Var, so long as the remote
Var determines the comparison collation. (When we actually ship such an
expression to the remote side, the local Var would become a Param with
default collation, meaning the remote Var would in fact control the
comparison collation, because non-default implicit collation overrides
default implicit collation in parse_collate.c.) To fix, be more precise
about what FDW_COLLATE_NONE means: it applies either to a noncollatable
data type or to a collatable type with default collation, if that collation
can't be traced to a remote Var. (When it can, FDW_COLLATE_SAFE is
appropriate.) We were essentially using that interpretation already at
the Var/Const/Param level, but we weren't bubbling it up properly.
An alternative fix would be to introduce a separate FDW_COLLATE_DEFAULT
value to describe the second situation, but that would add more code
without changing the actual behavior, so it didn't seem worthwhile.
Also, since we're clarifying the rule to be that we care about whether
operator/function input collations match, there seems no need to fail
immediately upon seeing a Const/Param/non-foreign-Var with nondefault
collation. We only have to reject if it appears in a collation-sensitive
context (for example, "var IS NOT NULL" is perfectly safe from a collation
standpoint, whatever collation the var has). So just set the state to
UNSAFE rather than failing immediately.
Per report from Jeevan Chalke. This essentially corrects some sloppy
thinking in commit ed3ddf918b, so back-patch
to 9.3 where that logic appeared.
The old minimum values are rather large, making it time consuming to
test related behaviour. Additionally the current limits, especially for
multixacts, can be problematic in space-constrained systems. 10000000
multixacts can contain a lot of members.
Since there's no good reason for the current limits, lower them a good
bit. Setting them to 0 would be a bad idea, triggering endless vacuums,
so still retain a limit.
While at it fix autovacuum_multixact_freeze_max_age to refer to
multixact.c instead of varsup.c.
Reviewed-By: Robert Haas
Discussion: CA+TgmoYmQPHcrc3GSs7vwvrbTkbcGD9Gik=OztbDGGrovkkEzQ@mail.gmail.com
Backpatch: back to 9.0 (in parts)
mul_var() postpones propagating carries until it risks overflow in its
internal digit array. However, the logic failed to account for the
possibility of overflow in the carry propagation step, allowing wrong
results to be generated in corner cases. We must slightly reduce the
when-to-propagate-carries threshold to avoid that.
Discovered and fixed by Dean Rasheed, with small adjustments by me.
This has been wrong since commit d72f6c7503,
so back-patch to all supported branches.
RemoveLocalLock() must consider the possibility that LockAcquireExtended()
failed to palloc the initial space for a locallock's lockOwners array.
I had evidently meant to cope with this hazard when the code was originally
written (commit 1785acebf2), but missed that
the pfree needed to be protected with an if-test. Just to make sure things
are left in a clean state, reset numLockOwners as well.
Per low-memory testing by Andreas Seltenreich. Back-patch to all supported
branches.
After an internal failure in shortest() or longest() while pinning down the
exact location of a match, find() forgot to free the DFA structure before
returning. This is pretty unlikely to occur, since we just successfully
ran the "search" variant of the DFA; but it could happen, and it would
result in a session-lifespan memory leak since this code uses malloc()
directly. Problem seems to have been aboriginal in Spencer's library,
so back-patch all the way.
In passing, correct a thinko in a comment I added awhile back about the
meaning of the "ntree" field.
I happened across these issues while comparing our code to Tcl's version
of the library.
This setting contains extra configuration for the temp instance, as used
in pg_regress' --temp-config flag.
Backpatch to 9.2 where test.sh was introduced.
The docs claimed that \uhhhh would be interpreted as a Unicode value
regardless of the database encoding, but it's never been implemented
that way: \uhhhh and \xhhhh actually mean exactly the same thing, namely
the character that pg_mb2wchar translates to 0xhhhh. Moreover we were
falsely dismissive of the usefulness of Unicode code points above FFFF.
Fix that.
It's been like this for ages, so back-patch to all supported branches.
Commit 5ddc72887a does not actually work
because it will happily blow away ri_constraint_cache entries that are
in active use in outer call levels. In any case, it's a very ugly,
brute-force solution to the problem of limiting the cache size.
Revert until it can be redesigned.
Modify pg_dump to restore postgres/template1 databases to non-default
tablespaces by switching out of the database to be moved, then switching
back.
Also, to fix potentially cases where the old/new tablespaces might not
match, fix pg_upgrade to process new/old tablespaces separately in all
cases.
Report by Marti Raudsepp
Patch by Marti Raudsepp, me
Backpatch through 9.0
Commit 45ba424f improved foreign key lookups during bulk updates
when the FK value does not change. When restoring a schema dump
from a database with many (say 100,000) foreign keys, this cache
would grow very big and every ALTER TABLE command was causing an
InvalidateConstraintCacheCallBack(), which uses a sequential hash
table scan. This could cause a severe performance regression in
restoring a schema dump (including during pg_upgrade).
The patch uses a heuristic method of detecting when the hash table
should be destroyed and recreated.
InvalidateConstraintCacheCallBack() adds the current size of the
hash table to a counter. When that sum reaches 1,000,000, the hash
table is flushed. This fixes the regression without noticeable
harm to the bulk update use case.
Jan Wieck
Backpatch to 9.3 where the performance regression was introduced.
The "typo" alleged in commit 1e460d4bd was actually a comment that was
correct when written, but I missed updating it in commit b5282aa89.
Use a slightly less specific (and hopefully more future-proof) description
of what is collected. Back-patch to 9.2 where that commit appeared, and
revert the comment to its then-entirely-correct state before that.
The list-wrangling here was done wrong, allowing the same state to get
put into the list twice. The following loop then would clone it twice.
The second clone would wind up with no inarcs, so that there was no
observable misbehavior AFAICT, but a useless state in the finished NFA
isn't an especially good thing.
This commit makes postmaster forcibly remove the files signaling
a standby promotion request. Otherwise, the existence of those files
can trigger a promotion too early, whether a user wants that or not.
This removal of files is usually unnecessary because they can exist
only during a few moments during a standby promotion. However
there is a race condition: if pg_ctl promote is executed and creates
the files during a promotion, the files can stay around even after
the server is brought up to new master. Then, if new standby starts
by using the backup taken from that master, the files can exist
at the server startup and should be removed in order to avoid
an unexpected promotion.
Back-patch to 9.1 where promote signal file was introduced.
Problem reported by Feike Steenbergen.
Original patch by Michael Paquier, modified by me.
Discussion: 20150528100705.4686.91426@wrigleys.postgresql.org
Even views considered "simple" enough to be automatically updatable may
have mulitple relations involved (eg: in a where clause). We need to
make sure and lock those relations when rewriting the query.
Back-patch to 9.3 where updatable views were added.
Pointed out by Andres, patch thanks to Dean Rasheed.
This was forgotten in 8a3631f (commit that originally added the parameter)
and 0ca9907 (commit that added the documentation later that year).
Back-patch to all supported versions.
We were missing a few return checks on OpenSSL calls. Should be pretty
harmless, since we haven't seen any user reports about problems, and
this is not a high-traffic module anyway; still, a bug is a bug, so
backpatch this all the way back to 9.0.
Author: Michael Paquier, while reviewing another sslinfo patch
Cleanup process could be called by ordinary insert/update and could take a lot
of time. Add vacuum_delay_point() to make this process interruptable. Under
vacuum this call will also throttle a vacuum process to decrease system load,
called from insert/update it will not throttle, and that reduces a latency.
Backpatch for all supported branches.
Jeff Janes <jeff.janes@gmail.com>
RESERV. RESERV is meant for tokens like "now" and having them in that
category throws errors like these when used as an input date:
stark=# SELECT 'doy'::timestamptz;
ERROR: unexpected dtype 33 while parsing timestamptz "doy"
LINE 1: SELECT 'doy'::timestamptz;
^
stark=# SELECT 'dow'::timestamptz;
ERROR: unexpected dtype 32 while parsing timestamptz "dow"
LINE 1: SELECT 'dow'::timestamptz;
^
Found by LLVM's Libfuzzer
This has been broken since 9.3 (commit 82b1b213ca to be exact),
which suggests that nobody is any longer using a Windows build system that
doesn't provide a symlink emulation. Still, it's wrong on its own terms,
so repair.
YUriy Zhuravlev
Formerly, we treated only portals created in the current subtransaction as
having failed during subtransaction abort. However, if the error occurred
while running a portal created in an outer subtransaction (ie, a cursor
declared before the last savepoint), that has to be considered broken too.
To allow reliable detection of which ones those are, add a bookkeeping
field to struct Portal that tracks the innermost subtransaction in which
each portal has actually been executed. (Without this, we'd end up
failing portals containing functions that had called the subtransaction,
thereby breaking plpgsql exception blocks completely.)
In addition, when we fail an outer-subtransaction Portal, transfer its
resources into the subtransaction's resource owner, so that they're
released early in cleanup of the subxact. This fixes a problem reported by
Jim Nasby in which a function executed in an outer-subtransaction cursor
could cause an Assert failure or crash by referencing a relation created
within the inner subtransaction.
The proximate cause of the Assert failure is that AtEOSubXact_RelationCache
assumed it could blow away a relcache entry without first checking that the
entry had zero refcount. That was a bad idea on its own terms, so add such
a check there, and to the similar coding in AtEOXact_RelationCache. This
provides an independent safety measure in case there are still ways to
provoke the situation despite the Portal-level changes.
This has been broken since subtransactions were invented, so back-patch
to all supported branches.
Tom Lane and Michael Paquier
The regression tests for sepgsql were broken by changes in the
base distro as-shipped policies. Specifically, definition of
unconfined_t in the system default policy was changed to bypass
multi-category rules, which the regression test depended on.
Fix that by defining a custom privileged domain
(sepgsql_regtest_superuser_t) and using it instead of system's
unconfined_t domain. The new sepgsql_regtest_superuser_t domain
performs almost like the current unconfined_t, but restricted by
multi-category policy as the traditional unconfined_t was.
The custom policy module is a self defined domain, and so should not
be affected by related future system policy changes. However, it still
uses the unconfined_u:unconfined_r pair for selinux-user and role.
Those definitions have not been changed for several years and seem
less risky to rely on than the unconfined_t domain. Additionally, if
we define custom user/role, they would need to be manually defined
at the operating system level, adding more complexity to an already
non-standard and complex regression test.
Back-patch to 9.3. The regression tests will need more work before
working correctly on 9.2. Starting with 9.2, sepgsql has had dependencies
on libselinux versions that are only available on newer distros with
the changed set of policies (e.g. RHEL 7.x). On 9.1 sepgsql works
fine with the older distros with original policy set (e.g. RHEL 6.x),
and on which the existing regression tests work fine. We might want
eventually change 9.1 sepgsql regression tests to be more independent
from the underlying OS policies, however more work will be needed to
make that happen and it is not clear that it is worth the effort.
Kohei KaiGai with review by Adam Brightwell and me, commentary by
Stephen, Alvaro, Tom, Robert, and others.
On recent AIX it's necessary to configure gcc to use the native assembler
(because the GNU assembler hasn't been updated to handle AIX 6+). This
caused PG builds to fail with assembler syntax errors, because we'd try
to compile s_lock.h's gcc asm fragment for PPC, and that assembly code
relied on GNU-style local labels. We can't substitute normal labels
because it would fail in any file containing more than one inlined use of
tas(). Fortunately, that code is stable enough, and the PPC ISA is simple
enough, that it doesn't seem like too much of a maintenance burden to just
hand-code the branch offsets, removing the need for any labels.
Note that the AIX assembler only accepts "$" for the location counter
pseudo-symbol. The usual GNU convention is "."; but it appears that all
versions of gas for PPC also accept "$", so in theory this patch will not
break any other PPC platforms.
This has been reported by a few people, but Steve Underwood gets the credit
for being the first to pursue the problem far enough to understand why it
was failing. Thanks also to Noah Misch for additional testing.
The default argument, if given, has to be of exactly the same datatype
as the first argument; but this was not stated in so many words, and
the error message you get about it might not lead your thought in the
right direction. Per bug #13587 from Robert McGehee.
A quick scan says that these are the only two built-in functions with two
anyelement arguments and no other polymorphic arguments. There are plenty
of cases of, eg, anyarray and anyelement, but those seem less likely to
confuse. For instance this doesn't seem terribly hard to figure out:
"function array_remove(integer[], numeric) does not exist". So I've
contented myself with fixing these two cases.
For no obvious reason, spi_printtup() was coded to enlarge the tuple
pointer table by just 256 slots at a time, rather than doubling the size at
each reallocation, as is our usual habit. For very large SPI results, this
makes for O(N^2) time spent in repalloc(), which of course soon comes to
dominate the runtime. Use the standard doubling approach instead.
This is a longstanding performance bug, so back-patch to all active
branches.
Neil Conway
PLyString_ToComposite() blithely overwrote proc->result.out.d, even though
for a composite result type the other union variant proc->result.out.r is
the one that should be valid. This could result in a crash if out.r had
in fact been filled in (proc->result.is_rowtype == 1) and then somebody
later attempted to use that data; as per bug #13579 from Paweł Michalak.
Just to add insult to injury, it didn't work for RECORD results anyway,
because record_in() would refuse the case.
Fix by doing the I/O function lookup in a local PLyTypeInfo variable,
as we were doing already in PLyObject_ToComposite(). This is not a great
technique because any fn_extra data allocated by the input function will
be leaked permanently (thanks to using TopMemoryContext as fn_mcxt).
But that's a pre-existing issue that is much less serious than a crash,
so leave it to be fixed separately.
This bug would be a potential security issue, except that plpython is
only available to superusers and the crash requires coding the function
in a way that didn't work before today's patches.
Add regression test cases covering all the supported methods of converting
composite results.
Back-patch to 9.1 where the faulty coding was introduced.
If we have the typmod that identifies a registered record type, there's no
reason that record_in() should refuse to perform input conversion for it.
Now, in direct SQL usage, record_in() will always be passed typmod = -1
with type OID RECORDOID, because no typmodin exists for type RECORD, so the
case can't arise. However, some InputFunctionCall users such as PLs may be
able to supply the right typmod, so we should allow this to support them.
Note: the previous coding and comment here predate commit 59c016aa9f.
There has been no case since 8.1 in which the passed type OID wouldn't be
valid; and if it weren't, this error message wouldn't be apropos anyway.
Better to let lookup_rowtype_tupdesc complain about it.
Back-patch to 9.1, as this is necessary for my upcoming plpython fix.
I'm committing it separately just to make it a bit more visible in the
commit history.
plpgsql's error location context messages ("PL/pgSQL function fn-name line
line-no at stmt-type") would misreport a CONTINUE statement as being an
EXIT, and misreport a MOVE statement as being a FETCH. These are clear
bugs that have been there a long time, so back-patch to all supported
branches.
In addition, in 9.5 and HEAD, change the description of EXECUTE from
"EXECUTE statement" to just plain EXECUTE; there seems no good reason why
this statement type should be described differently from others that have
a well-defined head keyword. And distinguish GET STACKED DIAGNOSTICS from
plain GET DIAGNOSTICS. These are a bit more of a judgment call, and also
affect existing regression-test outputs, so I did not back-patch into
stable branches.
Pavel Stehule and Tom Lane
This behavior wasn't documented, but it should be because it's user-visible
in triggers and other functions executed on the remote server.
Per question from Adam Fuchs.
Back-patch to 9.3 where postgres_fdw was added.
The table-rewriting forms of ALTER TABLE are MVCC-unsafe, in much the same
way as TRUNCATE, because they replace all rows of the table with newly-made
rows with a new xmin. (Ideally, concurrent transactions with old snapshots
would continue to see the old table contents, but the data is not there
anymore --- and if it were there, it would be inconsistent with the table's
updated rowtype, so there would be serious implementation problems to fix.)
This was nowhere documented though, and the problem was only documented for
TRUNCATE in a note in the TRUNCATE reference page. Create a new "Caveats"
section in the MVCC chapter that can be home to this and other limitations
on serializable consistency.
In passing, fix a mistaken statement that VACUUM and CLUSTER would reclaim
space occupied by a dropped column. They don't reconstruct existing tuples
so they couldn't do that.
Back-patch to all supported branches.
Doing so doesn't work if bool is a macro rather than a typedef.
Although c.h spends some effort to support configurations where bool is
a preexisting macro, help_config.c has existed this way since
2003 (b700a6), and there have not been any reports of
problems. Backpatch anyway since this is as riskless as it gets.
Discussion: 20150812084351.GD8470@awork2.anarazel.de
Backpatch: 9.0-master
In commit 95f4e59c32 I added a regression test case that examined
the plan of a query on system catalogs. That isn't a terribly great idea
because the catalogs tend to change from version to version, or even
within a version if someone makes an unrelated regression-test change that
populates the catalogs a bit differently. Usually I try to make planner
test cases rely on test tables that have not changed since Berkeley days,
but I got sloppy in this case because the submitted crasher example queried
the catalogs and I didn't spend enough time on rewriting it. But it was a
problem waiting to happen, as I was rudely reminded when I tried to port
that patch into Salesforce's Postgres variant :-(. So spend a little more
effort and rewrite the query to not use any system catalogs. I verified
that this version still provokes the Assert if 95f4e59c32866716's code fix
is reverted.
I also removed the EXPLAIN output from the test, as it turns out that the
assertion occurs while considering a plan that isn't the one ultimately
selected anyway; so there's no value in risking any cross-platform
variation in that printout.
Back-patch to 9.2, like the previous patch.
One of the changes I made in commit 8703059c6b turns out not to have
been such a good idea: we still need the exception in join_is_legal() that
allows a join if both inputs already overlap the RHS of the special join
we're checking. Otherwise we can miss valid plans, and might indeed fail
to find a plan at all, as in recent report from Andreas Seltenreich.
That code was added way back in commit c17117649b, but I failed to
include a regression test case then; my bad. Put it back with a better
explanation, and a test this time. The logic does end up a bit different
than before though: I now believe it's appropriate to make this check
first, thereby allowing such a case whether or not we'd consider the
previous SJ(s) to commute with this one. (Presumably, we already decided
they did; but it was confusing to have this consideration in the middle
of the code that was handling the other case.)
Back-patch to all active branches, like the previous patch.
actually check the returned pointer allocated, potentially NULL which
could be the result of a malloc call.
Issue noted by Coverity, fixed by Michael Paquier <michael@otacoo.com>
newnfa() failed to set the regex error state when malloc() fails.
Several places in regcomp.c failed to check for an error after calling
subre(). Each of these mistakes could lead to null-pointer-dereference
crashes in memory-starved backends.
Report and patch by Andreas Seltenreich. Back-patch to all branches.
pg_dump produced fairly silly GRANT/REVOKE commands when dumping types from
pre-9.2 servers, and when dumping functions or procedural languages from
pre-7.3 servers. Those server versions lack the typacl, proacl, and/or
lanacl columns respectively, and pg_dump substituted default values that
were in fact incorrect. We ended up revoking all the owner's own
privileges for the object while granting all privileges to PUBLIC.
Of course the owner would then have those privileges again via PUBLIC, so
long as she did not try to revoke PUBLIC's privileges; which may explain
the lack of field reports. Nonetheless this is pretty silly behavior.
The stakes were raised by my recent patch to make pg_dump dump shell types,
because 9.2 and up pg_dump would proceed to emit bogus GRANT/REVOKE
commands for a shell type if dumping from a pre-9.2 server; and the server
will not accept GRANT/REVOKE commands for a shell type. (Perhaps it
should, but that's a topic for another day.) So the resulting dump script
wouldn't load without errors.
The right thing to do is to act as though these objects have default
privileges (null ACL entries), which causes pg_dump to print no
GRANT/REVOKE commands at all for them. That fixes the silly results
and also dodges the problem with shell types.
In passing, modify getProcLangs() to be less creatively different about
how to handle missing columns when dumping from older server versions.
Every other data-acquisition function in pg_dump does that by substituting
appropriate default values in the version-specific SQL commands, and I see
no reason why this one should march to its own drummer. Its use of
"SELECT *" was likewise not conformant with anyplace else, not to mention
it's not considered good SQL style for production queries.
Back-patch to all supported versions. Although 9.0 and 9.1 pg_dump don't
have the issue with typacl, they are more likely than newer versions to be
used to dump from ancient servers, so we ought to fix the proacl/lanacl
issues all the way back.
Commit 85e5e222b1 turns out not to have taken
care of all cases of the partially-evaluatable-PlaceHolderVar problem found
by Andreas Seltenreich's fuzz testing. I had set it up to check for risky
PHVs only in the event that we were making a star-schema-based exception to
the param_source_rels join ordering heuristic. However, it turns out that
the problem can occur even in joins that satisfy the param_source_rels
heuristic, in which case allow_star_schema_join() isn't consulted.
Refactor so that we check for risky PHVs whenever the proposed join has
any remaining parameterization.
Back-patch to 9.2, like the previous patch (except for the regression test
case, which only works back to 9.3 because it uses LATERAL).
Note that this discovery implies that problems of this sort could've
occurred in 9.2 and up even before the star-schema patch; though I've not
tried to prove that experimentally.
