Noah Misch [Mon, 6 Nov 2017 15:11:10 +0000 (07:11 -0800)]
start-scripts: switch to $PGUSER before opening $PGLOG.
By default, $PGUSER has permission to unlink $PGLOG. If $PGUSER
replaces $PGLOG with a symbolic link, the server will corrupt the
link-targeted file by appending log messages. Since these scripts open
$PGLOG as root, the attack works regardless of target file ownership.
"make install" does not install these scripts anywhere. Users having
manually installed them in the past should repeat that process to
acquire this fix. Most script users have $PGLOG writable to root only,
located in $PGDATA. Just before updating one of these scripts, such
users should rename $PGLOG to $PGLOG.old. The script will then recreate
$PGLOG with proper ownership.
Reviewed by Peter Eisentraut. Reported by Antoine Scemama.
Tom Lane [Sun, 5 Nov 2017 18:47:57 +0000 (13:47 -0500)]
Release notes for 10.1, 9.6.6, 9.5.10, 9.4.15, 9.3.20, 9.2.24.
In the v10 branch, also back-patch the effects of 1ff01b390 and c29c57890
on these files, to reduce future maintenance issues. (I'd do it further
back, except that the 9.X branches differ anyway due to xlog-to-wal
link tag renaming.)
Tom Lane [Fri, 27 Oct 2017 22:16:25 +0000 (18:16 -0400)]
Dept of second thoughts: keep aliasp_item in sync with tlistitem.
Commit d5b760ecb wasn't quite right, on second thought: if the
caller didn't ask for column names then it would happily emit
more Vars than if the caller did ask for column names. This
is surely not a good idea. Advance the aliasp_item whether or
not we're preparing a colnames list.
Tom Lane [Fri, 27 Oct 2017 21:10:21 +0000 (17:10 -0400)]
Fix crash when columns have been added to the end of a view.
expandRTE() supposed that an RTE_SUBQUERY subquery must have exactly
as many non-junk tlist items as the RTE has column aliases for it.
This was true at the time the code was written, and is still true so
far as parse analysis is concerned --- but when the function is used
during planning, the subquery might have appeared through insertion
of a view that now has more columns than it did when the outer query
was parsed. This results in a core dump if, for instance, we have
to expand a whole-row Var that references the subquery.
To avoid crashing, we can either stop expanding the RTE when we run
out of aliases, or invent new aliases for the added columns. While
the latter might be more useful, the former is consistent with what
expandRTE() does for composite-returning functions in the RTE_FUNCTION
case, so it seems like we'd better do it that way.
Per bug #14876 from Samuel Horwitz. This has been busted since commit ff1ea2173 allowed views to acquire more columns, so back-patch to all
supported branches.
Tom Lane [Fri, 27 Oct 2017 16:18:57 +0000 (12:18 -0400)]
Rethink the dependencies recorded for FieldSelect/FieldStore nodes.
On closer investigation, commits f3ea3e3e8 et al were a few bricks
shy of a load. What we need is not so much to lock down the result
type of a FieldSelect, as to lock down the existence of the column
it's trying to extract. Otherwise, we can break it by dropping that
column. The dependency on the result type is then held indirectly
through the column, and doesn't need to be recorded explicitly.
Out of paranoia, I left in the code to record a dependency on the
result type, but it's used only if we can't identify the pg_class OID
for the column. That shouldn't ever happen right now, AFAICS, but
it seems possible that in future the input node could be marked as
being of type RECORD rather than some specific composite type.
Likewise for FieldStore.
Like the previous patch, back-patch to all supported branches.
Andrew Dunstan [Thu, 26 Oct 2017 14:10:37 +0000 (10:10 -0400)]
Improve gendef.pl diagnostic on failure to open sym file
There have been numerous buildfarm failures but the diagnostic is
currently silent about the reason for failure to open the file. Let's
see if we can get to the bottom of it.
Tom Lane [Wed, 25 Oct 2017 23:32:25 +0000 (19:32 -0400)]
Fix libpq to not require user's home directory to exist.
Some people like to run libpq-using applications in environments where
there's no home directory. We've broken that scenario before (cf commits 5b4067798 and bd58d9d88), and commit ba005f193 broke it again, by making
it a hard error if we fail to get the home directory name while looking
for ~/.pgpass. The previous precedent is that if we can't get the home
directory name, we should just silently act as though the file we hoped
to find there doesn't exist. Rearrange the new code to honor that.
Looking around, the service-file code added by commit 41a4e4595 had the
same disease. Apparently, that escaped notice because it only runs when
a service name has been specified, which I guess the people who use this
scenario don't do. Nonetheless, it's wrong too, so fix that case as well.
Add a comment about this policy to pqGetHomeDirectory, in the probably
vain hope of forestalling the same error in future. And upgrade the
rather miserable commenting in parseServiceInfo, too.
In passing, also back off parseServiceInfo's assumption that only ENOENT
is an ignorable error from stat() when checking a service file. We would
need to ignore at least ENOTDIR as well (cf 5b4067798), and seeing that
the far-better-tested code for ~/.pgpass treats all stat() failures alike,
I think this code ought to as well.
Per bug #14872 from Dan Watson. Back-patch the .pgpass change to v10
where ba005f193 came in. The service-file bugs are far older, so
back-patch the other changes to all supported branches.
Tom Lane [Mon, 23 Oct 2017 22:15:36 +0000 (18:15 -0400)]
Update time zone data files to tzdata release 2017c.
DST law changes in Fiji, Namibia, Northern Cyprus, Sudan, Tonga,
and Turks & Caicos Islands. Historical corrections for Alaska, Apia,
Burma, Calcutta, Detroit, Ireland, Namibia, and Pago Pago.
Tom Lane [Mon, 23 Oct 2017 21:54:09 +0000 (17:54 -0400)]
Sync our copy of the timezone library with IANA release tzcode2017c.
This is a trivial update containing only cosmetic changes. The point
is just to get back to being synced with an official release of tzcode,
rather than some ad-hoc point in their commit history, which is where
commit 47f849a3c left it.
Tom Lane [Mon, 23 Oct 2017 17:57:46 +0000 (13:57 -0400)]
Fix some oversights in expression dependency recording.
find_expr_references() neglected to record a dependency on the result type
of a FieldSelect node, allowing a DROP TYPE to break a view or rule that
contains such an expression. I think we'd omitted this case intentionally,
reasoning that there would always be a related dependency ensuring that the
DROP would cascade to the view. But at least with nested field selection
expressions, that's not true, as shown in bug #14867 from Mansur Galiev.
Add the dependency, and for good measure a dependency on the node's exposed
collation.
Likewise add a dependency on the result type of a FieldStore. I think here
the reasoning was that it'd only appear within an assignment to a field,
and the dependency on the field's column would be enough ... but having
seen this example, I think that's wrong for nested-composites cases.
Looking at nearby code, I notice we're not recording a dependency on the
exposed collation of CoerceViaIO, which seems inconsistent with our choices
for related node types. Maybe that's OK but I'm feeling suspicious of this
code today, so let's add that; it certainly can't hurt.
This patch does not do anything to protect already-existing views, only
views created after it's installed. But seeing that the issue has been
there a very long time and nobody noticed till now, that's probably good
enough.
Tom Lane [Fri, 20 Oct 2017 21:12:28 +0000 (17:12 -0400)]
Fix typcache's failure to treat ranges as container types.
Like the similar logic for arrays and records, it's necessary to examine
the range's subtype to decide whether the range type can support hashing.
We can omit checking the subtype for btree-defined operations, though,
since range subtypes are required to have those operations. (Possibly
that simplification for btree cases led us to overlook that it does
not apply for hash cases.)
This is only an issue if the subtype lacks hash support, which is not
true of any built-in range type, but it's easy to demonstrate a problem
with a range type over, eg, money: you can get a "could not identify
a hash function" failure when the planner is misled into thinking that
hash join or aggregation would work.
This was born broken, so back-patch to all supported branches.
Tom Lane [Wed, 11 Oct 2017 20:56:23 +0000 (16:56 -0400)]
Doc: fix missing explanation of default object privileges.
The GRANT reference page, which lists the default privileges for new
objects, failed to mention that USAGE is granted by default for data
types and domains. As a lesser sin, it also did not specify anything
about the initial privileges for sequences, FDWs, foreign servers,
or large objects. Fix that, and add a comment to acldefault() in the
probably vain hope of getting people to maintain this list in future.
Noted by Laurenz Albe, though I editorialized on the wording a bit.
Back-patch to all supported branches, since they all have this behavior.
Tom Lane [Wed, 11 Oct 2017 18:28:34 +0000 (14:28 -0400)]
Fix low-probability loss of NOTIFY messages due to XID wraparound.
Up to now async.c has used TransactionIdIsInProgress() to detect whether
a notify message's source transaction is still running. However, that
function has a quick-exit path that reports that XIDs before RecentXmin
are no longer running. If a listening backend is doing nothing but
listening, and not running any queries, there is nothing that will advance
its value of RecentXmin. Once 2 billion transactions elapse, the
RecentXmin check causes active transactions to be reported as not running.
If they aren't committed yet according to CLOG, async.c decides they
aborted and discards their messages. The timing for that is a bit tight
but it can happen when multiple backends are sending notifies concurrently.
The net symptom therefore is that a sufficiently-long-surviving
listen-only backend starts to miss some fraction of NOTIFY traffic,
but only under heavy load.
The only function that updates RecentXmin is GetSnapshotData().
A brute-force fix would therefore be to take a snapshot before
processing incoming notify messages. But that would add cycles,
as well as contention for the ProcArrayLock. We can be smarter:
having taken the snapshot, let's use that to check for running
XIDs, and not call TransactionIdIsInProgress() at all. In this
way we reduce the number of ProcArrayLock acquisitions from one
per message to one per notify interrupt; that's the same under
light load but should be a benefit under heavy load. Light testing
says that this change is a wash performance-wise for normal loads.
I looked around for other callers of TransactionIdIsInProgress()
that might be at similar risk, and didn't find any; all of them
are inside transactions that presumably have already taken a
snapshot.
Problem report and diagnosis by Marko Tiikkaja, patch by me.
Back-patch to all supported branches, since it's been like this
since 9.0.
Tom Lane [Fri, 6 Oct 2017 16:20:13 +0000 (12:20 -0400)]
Fix access-off-end-of-array in clog.c.
Sloppy loop coding in set_status_by_pages() resulted in fetching one array
element more than it should from the subxids[] array. The odds of this
resulting in SIGSEGV are pretty small, but we've certainly seen that happen
with similar mistakes elsewhere. While at it, we can get rid of an extra
TransactionIdToPage() calculation per loop.
Per report from David Binderman. Back-patch to all supported branches,
since this code is quite old.
Alvaro Herrera [Tue, 3 Oct 2017 12:58:25 +0000 (14:58 +0200)]
Fix coding rules violations in walreceiver.c
1. Since commit b1a9bad9e744 we had pstrdup() inside a
spinlock-protected critical section; reported by Andreas Seltenreich.
Turn those into strlcpy() to stack-allocated variables instead.
Backpatch to 9.6.
2. Since commit 9ed551e0a4fd we had a pfree() uselessly inside a
spinlock-protected critical section. Tom Lane noticed in code review.
Move down. Backpatch to 9.6.
3. Since commit 64233902d22b we had GetCurrentTimestamp() (a kernel
call) inside a spinlock-protected critical section. Tom Lane noticed in
code review. Move it up. Backpatch to 9.2.
4. Since commit 1bb2558046cc we did elog(PANIC) while holding spinlock.
Tom Lane noticed in code review. Release spinlock before dying.
Backpatch to 9.2.
Tom Lane [Wed, 27 Sep 2017 21:05:54 +0000 (17:05 -0400)]
Fix behavior when converting a float infinity to numeric.
float8_numeric() and float4_numeric() failed to consider the possibility
that the input is an IEEE infinity. The results depended on the
platform-specific behavior of sprintf(): on most platforms you'd get
something like
ERROR: invalid input syntax for type numeric: "inf"
but at least on Windows it's possible for the conversion to succeed and
deliver a finite value (typically 1), due to a nonstandard output format
from sprintf and lack of syntax error checking in these functions.
Since our numeric type lacks the concept of infinity, a suitable conversion
is impossible; the best thing to do is throw an explicit error before
letting sprintf do its thing.
While at it, let's use snprintf not sprintf. Overrunning the buffer
should be impossible if sprintf does what it's supposed to, but this
is cheap insurance against a stack smash if it doesn't.
Problem reported by Taiki Kondo. Patch by me based on fix suggestion
from KaiGai Kohei. Back-patch to all supported branches.
It drops objects outside information_schema that depend on objects
inside information_schema. For example, it will drop a user-defined
view if the view query refers to information_schema.
Peter Eisentraut [Fri, 22 Sep 2017 20:50:59 +0000 (16:50 -0400)]
Fix saving and restoring umask
In two cases, we set a different umask for some piece of code and
restore it afterwards. But if the contained code errors out, the umask
is not restored. So add TRY/CATCH blocks to fix that.
Tom Lane [Fri, 22 Sep 2017 04:04:21 +0000 (00:04 -0400)]
Sync our copy of the timezone library with IANA tzcode master.
This patch absorbs a few unreleased fixes in the IANA code.
It corresponds to commit 2d8b944c1cec0808ac4f7a9ee1a463c28f9cd00a
in https://github.com/eggert/tz. Non-cosmetic changes include:
TZDEFRULESTRING is updated to match current US DST practice,
rather than what it was over ten years ago. This only matters
for interpretation of POSIX-style zone names (e.g., "EST5EDT"),
and only if the timezone database doesn't include either an exact
match for the zone name or a "posixrules" entry. The latter
should not be true in any current Postgres installation, but
this could possibly matter when using --with-system-tzdata.
Get rid of a nonportable use of "++var" on a bool var.
This is part of a larger fix that eliminates some vestigial
support for consecutive leap seconds, and adds checks to
the "zic" compiler that the data files do not specify that.
Remove a couple of ancient compatibility hacks. The IANA
crew think these are obsolete, and I tend to agree. But
perhaps our buildfarm will think different.
Back-patch to all supported branches, in line with our policy
that all branches should be using current IANA code. Before v10,
this includes application of current pgindent rules, to avoid
whitespace problems in future back-patches.
Tom Lane [Thu, 21 Sep 2017 22:13:11 +0000 (18:13 -0400)]
Give a better error for duplicate entries in VACUUM/ANALYZE column list.
Previously, the code didn't think about this case and would just try to
analyze such a column twice. That would fail at the point of inserting
the second version of the pg_statistic row, with obscure error messsages
like "duplicate key value violates unique constraint" or "tuple already
updated by self", depending on context and PG version. We could allow
the case by ignoring duplicate column specifications, but it seems better
to reject it explicitly.
The bogus error messages seem like arguably a bug, so back-patch to
all supported versions.
Nathan Bossart, per a report from Michael Paquier, and whacked
around a bit by me.
Tom Lane [Sun, 17 Sep 2017 18:50:01 +0000 (14:50 -0400)]
Fix possible dangling pointer dereference in trigger.c.
AfterTriggerEndQuery correctly notes that the query_stack could get
repalloc'd during a trigger firing, but it nonetheless passes the address
of a query_stack entry to afterTriggerInvokeEvents, so that if such a
repalloc occurs, afterTriggerInvokeEvents is already working with an
obsolete dangling pointer while it scans the rest of the events. Oops.
The only code at risk is its "delete_ok" cleanup code, so we can
prevent unsafe behavior by passing delete_ok = false instead of true.
However, that could have a significant performance penalty, because the
point of passing delete_ok = true is to not have to re-scan possibly
a large number of dead trigger events on the next time through the loop.
There's more than one way to skin that cat, though. What we can do is
delete all the "chunks" in the event list except the last one, since
we know all events in them must be dead. Deleting the chunks is work
we'd have had to do later in AfterTriggerEndQuery anyway, and it ends
up saving rescanning of just about the same events we'd have gotten
rid of with delete_ok = true.
In v10 and HEAD, we also have to be careful to mop up any per-table
after_trig_events pointers that would become dangling. This is slightly
annoying, but I don't think that normal use-cases will traverse this code
path often enough for it to be a performance problem.
It's pretty hard to hit this in practice because of the unlikelihood
of the query_stack getting resized at just the wrong time. Nonetheless,
it's definitely a live bug of ancient standing, so back-patch to all
supported branches.
Tom Lane [Sun, 3 Sep 2017 15:01:08 +0000 (11:01 -0400)]
Fix macro-redefinition warning on MSVC.
In commit 9d6b160d7, I tweaked pg_config.h.win32 to use
"#define HAVE_LONG_LONG_INT_64 1" rather than defining it as empty,
for consistency with what happens in an autoconf'd build.
But Solution.pm injects another definition of that macro into
ecpg_config.h, leading to justifiable (though harmless) compiler whining.
Make that one consistent too. Back-patch, like the previous patch.
Tom Lane [Fri, 1 Sep 2017 19:14:18 +0000 (15:14 -0400)]
Make [U]INT64CONST safe for use in #if conditions.
Instead of using a cast to force the constant to be the right width,
assume we can plaster on an L, UL, LL, or ULL suffix as appropriate.
The old approach to this is very hoary, dating from before we were
willing to require compilers to have working int64 types.
This fix makes the PG_INT64_MIN, PG_INT64_MAX, and PG_UINT64_MAX
constants safe to use in preprocessor conditions, where a cast
doesn't work. Other symbolic constants that might be defined using
[U]INT64CONST are likewise safer than before.
Also fix the SIZE_MAX macro to be similarly safe, if we are forced
to provide a definition for that. The test added in commit 2e70d6b5e
happens to do what we want even with the hack "(size_t) -1" definition,
but we could easily get burnt on other tests in future.
Back-patch to all supported branches, like the previous commits.
Tom Lane [Fri, 1 Sep 2017 17:52:54 +0000 (13:52 -0400)]
Ensure SIZE_MAX can be used throughout our code.
Pre-C99 platforms may lack <stdint.h> and thereby SIZE_MAX. We have
a couple of places using the hack "(size_t) -1" as a fallback, but
it wasn't universally available; which means the code added in commit 2e70d6b5e fails to compile everywhere. Move that hack to c.h so that
we can rely on having SIZE_MAX everywhere.
Per discussion, it'd be a good idea to make the macro's value safe
for use in #if-tests, but that will take a bit more work. This is
just a quick expedient to get the buildfarm green again.
Back-patch to all supported branches, like the previous commit.
Tom Lane [Tue, 29 Aug 2017 19:38:05 +0000 (15:38 -0400)]
Doc: document libpq's restriction to INT_MAX rows in a PGresult.
As long as PQntuples, PQgetvalue, etc, use "int" for row numbers, we're
pretty much stuck with this limitation. The documentation formerly stated
that the result of PQntuples "might overflow on 32-bit operating systems",
which is just nonsense: that's not where the overflow would happen, and
if you did reach an overflow it would not be on a 32-bit machine, because
you'd have OOM'd long since.
Tom Lane [Tue, 29 Aug 2017 19:18:01 +0000 (15:18 -0400)]
Teach libpq to detect integer overflow in the row count of a PGresult.
Adding more than 1 billion rows to a PGresult would overflow its ntups and
tupArrSize fields, leading to client crashes. It'd be desirable to use
wider fields on 64-bit machines, but because all of libpq's external APIs
use plain "int" for row counters, that's going to be hard to accomplish
without an ABI break. Given the lack of complaints so far, and the general
pain that would be involved in using such huge PGresults, let's settle for
just preventing the overflow and reporting a useful error message if it
does happen. Also, for a couple more lines of code we can increase the
threshold of trouble from INT_MAX/2 to INT_MAX rows.
To do that, refactor pqAddTuple() to allow returning an error message that
replaces the default assumption that it failed because of out-of-memory.
Along the way, fix PQsetvalue() so that it reports all failures via
pqInternalNotice(). It already did so in the case of bad field number,
but neglected to report anything for other error causes.
Because of the potential for crashes, this seems like a back-patchable
bug fix, despite the lack of field reports.
Tom Lane [Tue, 29 Aug 2017 13:34:21 +0000 (09:34 -0400)]
Improve docs about numeric formatting patterns (to_char/to_number).
The explanation about "0" versus "9" format characters was confusing
and arguably wrong; the discussion of sign handling wasn't very good
either. Notably, while it's accurate to say that "FM" strips leading
zeroes in date/time values, what it really does with numeric values
is to strip *trailing* zeroes, and then only if you wrote "9" rather
than "0". Per gripes from Erwin Brandstetter.
Andres Freund [Tue, 22 Aug 2017 14:46:05 +0000 (07:46 -0700)]
Backpatch introduction of TupleDescAttr(tupdesc, i).
2cd70845240 / c6293249d change the way individual attributes in a
TupleDesc are stored / accessed. To reduce the effort of making
extensions compatible with postgresql 11, and to ease future
backpatching, backpatch introduction of TupleDescAttr() to all
releases. Do not backpatch change in storage, as that'd be a breaking
change for existing and working extensions.
Author: Andres Freund
Discussion: https://postgr.es/m/20170820181723.tdswdinzptbcwhrr@alap3.anarazel.de
Backpatch: 9.2-
Tom Lane [Thu, 17 Aug 2017 17:15:46 +0000 (13:15 -0400)]
Further tweaks to compiler flags for PL/Perl on Windows.
It now emerges that we can only rely on Perl to tell us we must use
-D_USE_32BIT_TIME_T if it's Perl 5.13.4 or later. For older versions,
revert to our previous practice of assuming we need that symbol in
all 32-bit Windows builds. This is not ideal, but inquiring into
which compiler version Perl was built with seems far too fragile.
In any case, we had not previously had complaints about these old
Perl versions, so let's assume this is Good Enough. (It's still
better than the situation ante commit 5a5c2feca, in that at least
the effects are confined to PL/Perl rather than the whole PG build.)
Back-patch to all supported versions, like 5a5c2feca and predecessors.
Tom Lane [Mon, 14 Aug 2017 19:43:20 +0000 (15:43 -0400)]
Handle elog(FATAL) during ROLLBACK more robustly.
Stress testing by Andreas Seltenreich disclosed longstanding problems that
occur if a FATAL exit (e.g. due to receipt of SIGTERM) occurs while we are
trying to execute a ROLLBACK of an already-failed transaction. In such a
case, xact.c is in TBLOCK_ABORT state, so that AbortOutOfAnyTransaction
would skip AbortTransaction and go straight to CleanupTransaction. This
led to an assert failure in an assert-enabled build (due to the ROLLBACK's
portal still having a cleanup hook) or without assertions, to a FATAL exit
complaining about "cannot drop active portal". The latter's not
disastrous, perhaps, but it's messy enough to want to improve it.
We don't really want to run all of AbortTransaction in this code path.
The minimum required to clean up the open portal safely is to do
AtAbort_Memory and AtAbort_Portals. It seems like a good idea to
do AtAbort_Memory unconditionally, to be entirely sure that we are
starting with a safe CurrentMemoryContext. That means that if the
main loop in AbortOutOfAnyTransaction does nothing, we need an extra
step at the bottom to restore CurrentMemoryContext = TopMemoryContext,
which I chose to do by invoking AtCleanup_Memory. This'll result in
calling AtCleanup_Memory twice in many of the paths through this function,
but that seems harmless and reasonably inexpensive.
The original motivation for the assertion in AtCleanup_Portals was that
we wanted to be sure that any user-defined code executed as a consequence
of the cleanup hook runs during AbortTransaction not CleanupTransaction.
That still seems like a valid concern, and now that we've seen one case
of the assertion firing --- which means that exactly that would have
happened in a production build --- let's replace the Assert with a runtime
check. If we see the cleanup hook still set, we'll emit a WARNING and
just drop the hook unexecuted.
This has been like this a long time, so back-patch to all supported
branches.
Tom Lane [Mon, 14 Aug 2017 15:48:59 +0000 (11:48 -0400)]
Absorb -D_USE_32BIT_TIME_T switch from Perl, if relevant.
Commit 3c163a7fc's original choice to ignore all #define symbols whose
names begin with underscore turns out to be too simplistic. On Windows,
some Perl installations are built with -D_USE_32BIT_TIME_T, and we must
absorb that or we get the wrong result for sizeof(PerlInterpreter).
This effectively re-reverts commit ef58b87df, which injected that symbol
in a hacky way, making it apply to all of Postgres not just PL/Perl.
More significantly, it did so on *all* 32-bit Windows builds, even when
the Perl build to be used did not select this option; so that it fails
to work properly with some newer Perl builds.
By making this change, we would be introducing an ABI break in 32-bit
Windows builds; but fortunately we have not used type time_t in any
exported Postgres APIs in a long time. So it should be OK, both for
PL/Perl itself and for third-party extensions, if an extension library
is built with a different _USE_32BIT_TIME_T setting than the core code.
Patch by me, based on research by Ashutosh Sharma and Robert Haas.
Back-patch to all supported branches, as commit 3c163a7fc was.
Tom Lane [Sun, 13 Aug 2017 20:15:14 +0000 (16:15 -0400)]
Remove AtEOXact_CatCache().
The sole useful effect of this function, to check that no catcache
entries have positive refcounts at transaction end, has really been
obsolete since we introduced ResourceOwners in PG 8.1. We reduced the
checks to assertions years ago, so that the function was a complete
no-op in production builds. There have been previous discussions about
removing it entirely, but consensus up to now was that it had some small
value as a cross-check for bugs in the ResourceOwner logic.
However, it now emerges that it's possible to trigger these assertions
if you hit an assert-enabled backend with SIGTERM during a call to
SearchCatCacheList, because that function temporarily increases the
refcounts of entries it's intending to add to a catcache list construct.
In a normal ERROR scenario, the extra refcounts are cleaned up by
SearchCatCacheList's PG_CATCH block; but in a FATAL exit we do a
transaction abort and exit without ever executing PG_CATCH handlers.
There's a case to be made that this is a generic hazard and we should
consider restructuring elog(FATAL) handling so that pending PG_CATCH
handlers do get run. That's pretty scary though: it could easily create
more problems than it solves. Preliminary stress testing by Andreas
Seltenreich suggests that there are not many live problems of this ilk,
so we rejected that idea.
There are more-localized ways to fix the problem; the most principled
one would be to use PG_ENSURE_ERROR_CLEANUP instead of plain PG_TRY.
But adding cycles to SearchCatCacheList isn't very appealing. We could
also weaken the assertions in AtEOXact_CatCache in some more or less
ad-hoc way, but that just makes its raison d'etre even less compelling.
In the end, the most reasonable solution seems to be to just remove
AtEOXact_CatCache altogether, on the grounds that it's not worth trying
to fix it. It hasn't found any bugs for us in many years.
Per report from Jeevan Chalke. Back-patch to all supported branches.
Tom Lane [Wed, 9 Aug 2017 21:03:10 +0000 (17:03 -0400)]
Fix handling of container types in find_composite_type_dependencies.
find_composite_type_dependencies correctly found columns that are of
the specified type, and columns that are of arrays of that type, but
not columns that are domains or ranges over the given type, its array
type, etc. The most general way to handle this seems to be to assume
that any type that is directly dependent on the specified type can be
treated as a container type, and processed recursively (allowing us
to handle nested cases such as ranges over domains over arrays ...).
Since a type's array type already has such a dependency, we can drop
the existing special case for the array type.
The very similar logic in get_rels_with_domain was likewise a few
bricks shy of a load, as it supposed that a directly dependent type
could *only* be a sub-domain. This is already wrong for ranges over
domains, and it'll someday be wrong for arrays over domains.
Add test cases illustrating the problems, and back-patch to all
supported branches.
Noah Misch [Mon, 7 Aug 2017 14:09:28 +0000 (07:09 -0700)]
Again match pg_user_mappings to information_schema.user_mapping_options.
Commit 3eefc51053f250837c3115c12f8119d16881a2d7 claimed to make
pg_user_mappings enforce the qualifications user_mapping_options had
been enforcing, but its removal of a longstanding restriction left them
distinct when the current user is the subject of a mapping yet has no
server privileges. user_mapping_options emits no rows for such a
mapping, but pg_user_mappings includes full umoptions. Change
pg_user_mappings to show null for umoptions. Back-patch to 9.2, like
the above commit.
Some authentication methods allowed it, others did not. In the client-side,
libpq does not even try to authenticate with an empty password, which makes
using empty passwords hazardous: an administrator might think that an
account with an empty password cannot be used to log in, because psql
doesn't allow it, and not realize that a different client would in fact
allow it. To clear that confusion and to be be consistent, disallow empty
passwords in all authentication methods.
All the authentication methods that used plaintext authentication over the
wire, except for BSD authentication, already checked that the password
received from the user was not empty. To avoid forgetting it in the future
again, move the check to the recv_password_packet function. That only
forbids using an empty password with plaintext authentication, however.
MD5 and SCRAM need a different fix:
* In stable branches, check that the MD5 hash stored for the user does not
not correspond to an empty string. This adds some overhead to MD5
authentication, because the server needs to compute an extra MD5 hash, but
it is not noticeable in practice.
* In HEAD, modify CREATE and ALTER ROLE to clear the password if an empty
string, or a password hash that corresponds to an empty string, is
specified. The user-visible behavior is the same as in the stable branches,
the user cannot log in, but it seems better to stop the empty password from
entering the system in the first place. Secondly, it is fairly expensive to
check that a SCRAM hash doesn't correspond to an empty string, because
computing a SCRAM hash is much more expensive than an MD5 hash by design,
so better avoid doing that on every authentication.
We could clear the password on CREATE/ALTER ROLE also in stable branches,
but we would still need to check at authentication time, because even if we
prevent empty passwords from being stored in pg_authid, there might be
existing ones there already.
Reported by Jeroen van der Ham, Ben de Graaff and Jelte Fennema.
Tom Lane [Fri, 4 Aug 2017 15:07:11 +0000 (11:07 -0400)]
Disallow SSL session tickets.
We don't actually support session tickets, since we do not create an SSL
session identifier. But it seems that OpenSSL will issue a session ticket
on-demand anyway, which will then fail when used. This results in
reconnection failures when using ticket-aware client-side SSL libraries
(such as the Npgsql .NET driver), as reported by Shay Rojansky.
To fix, just tell OpenSSL not to issue tickets. At some point in the
far future, we might consider enabling tickets instead. But the security
implications of that aren't entirely clear; and besides it would have
little benefit except for very short-lived database connections, which is
Something We're Bad At anyhow. It would take a lot of other work to get
to a point where that would really be an exciting thing to do.
While at it, also tell OpenSSL not to use a session cache. This doesn't
really do anything, since a backend would never populate the cache anyway,
but it might gain some micro-efficiencies and/or reduce security
exposures.
Patch by me, per discussion with Heikki Linnakangas and Shay Rojansky.
Back-patch to all supported versions.
Tom Lane [Wed, 2 Aug 2017 20:55:03 +0000 (16:55 -0400)]
Add pgtcl back to the list of externally-maintained client interfaces.
FlightAware is still maintaining this, and indeed is seemingly being
more active with it than the pgtclng fork is. List both, for the
time being anyway.
In the back branches, also back-port commit e20f679f6 and other
recent updates to the client-interfaces list. I think these are
probably of current interest to users of back branches. I did
not touch the list of externally maintained PLs in the back
branches, though. Those are much more likely to be server version
sensitive, and I don't know which of these PLs work all the way back.
Tom Lane [Wed, 2 Aug 2017 19:07:21 +0000 (15:07 -0400)]
Silence warning from modern perl about unescaped braces
Back-patch commit 76a1c97bf21c301f61bb41345e0cdd0d365b2086 into
the older branches (9.5 and before). This is needed because perl
5.26 and later treats the case as an error not just a warning.
Original patch by Andrew Dunstan, need for back-patch noted by
Ashutosh Sharma
Tom Lane [Mon, 31 Jul 2017 17:42:48 +0000 (13:42 -0400)]
Doc: specify that the minimum supported version of Perl is 5.8.3.
Previously the docs just said "5.8 or later". Experimentation shows
that while you can build on Unix from a git checkout with 5.8.0,
compiling recent PL/Perl requires at least 5.8.1, and you won't be
able to run the TAP tests with less than 5.8.3 because that's when
they added "prove". (I do not have any information on just what the
MSVC build scripts require.)
Since all these versions are quite ancient, let's not split hairs
in the docs, but just say that 5.8.3 is the minimum requirement.
Tom Lane [Wed, 26 Jul 2017 23:35:35 +0000 (19:35 -0400)]
Clean up SQL emitted by psql/describe.c.
Fix assorted places that had not bothered with the convention of
prefixing catalog and function names with "pg_catalog.". That
could possibly result in query failure when running with a nondefault
search_path. Also fix two places that weren't quoting OID literals.
I think the latter hasn't mattered much since about 7.3, but it's still
a bad idea to be doing it in 99 places and not in 2 others.
Also remove a useless EXISTS sub-select that someone had stuck into
describeOneTableDetails' queries for child tables. We just got the OID
out of pg_class, so I hardly see how checking that it exists in pg_class
was doing anything helpful.
In passing, try to improve the emitted formatting of a couple of
these queries, though I didn't work really hard on that. And merge
unnecessarily duplicative coding in some other places.
Much of this was new in HEAD, but some was quite old; back-patch
as appropriate.
Tom Lane [Mon, 24 Jul 2017 20:45:47 +0000 (16:45 -0400)]
Fix race condition in predicate-lock init code in EXEC_BACKEND builds.
Trading a little too heavily on letting the code path be the same whether
we were creating shared data structures or only attaching to them,
InitPredicateLocks() inserted the "scratch" PredicateLockTargetHash entry
unconditionally. This is just wrong if we're in a postmaster child,
which would only reach this code in EXEC_BACKEND builds. Most of the
time, the hash_search(HASH_ENTER) call would simply report that the
entry already existed, causing no visible effect since the code did not
bother to check for that possibility. However, if this happened while
some other backend had transiently removed the "scratch" entry, then
that other backend's eventual RestoreScratchTarget would suffer an
assert failure; this appears to be the explanation for a recent failure
on buildfarm member culicidae. In non-assert builds, there would be
no visible consequences there either. But nonetheless this is a pretty
bad bug for EXEC_BACKEND builds, for two reasons:
1. Each new backend would perform the hash_search(HASH_ENTER) call
without holding any lock that would prevent concurrent access to the
PredicateLockTargetHash hash table. This creates a low but certainly
nonzero risk of corruption of that hash table.
2. In the event that the race condition occurred, by reinserting the
scratch entry too soon, we were defeating the entire purpose of the
scratch entry, namely to guarantee that transaction commit could move
hash table entries around with no risk of out-of-memory failure.
The odds of an actual OOM failure are quite low, but not zero, and if
it did happen it would again result in corruption of the hash table.
The user-visible symptoms of such corruption are a little hard to predict,
but would presumably amount to misbehavior of SERIALIZABLE transactions
that'd require a crash or postmaster restart to fix.
To fix, just skip the hash insertion if IsUnderPostmaster. I also
inserted a bunch of assertions that the expected things happen
depending on whether IsUnderPostmaster is true. That might be overkill,
since most comparable code in other functions isn't quite that paranoid,
but once burnt twice shy.
In passing, also move a couple of lines to places where they seemed
to make more sense.
Diagnosis of problem by Thomas Munro, patch by me. Back-patch to
all supported branches.
Tom Lane [Mon, 24 Jul 2017 19:16:31 +0000 (15:16 -0400)]
Ensure that pg_get_ruledef()'s output matches pg_get_viewdef()'s.
Various cases involving renaming of view columns are handled by having
make_viewdef pass down the view's current relation tupledesc to
get_query_def, which then takes care to use the column names from the
tupledesc for the output column names of the SELECT. For some reason
though, we'd missed teaching make_ruledef to do similarly when it is
printing an ON SELECT rule, even though this is exactly the same case.
The results from pg_get_ruledef would then be different and arguably wrong.
In particular, this breaks pre-v10 versions of pg_dump, which in some
situations would define views by means of emitting a CREATE RULE ... ON
SELECT command. Third-party tools might not be happy either.
In passing, clean up some crufty code in make_viewdef; we'd apparently
modernized the equivalent code in make_ruledef somewhere along the way,
and missed this copy.
Per report from Gilles Darold. Back-patch to all supported versions.
Tom Lane [Thu, 20 Jul 2017 16:41:26 +0000 (12:41 -0400)]
Doc: clarify description of degenerate NATURAL joins.
Claiming that NATURAL JOIN is equivalent to CROSS JOIN when there are
no common column names is only strictly correct if it's an inner join;
you can't say e.g. CROSS LEFT JOIN. Better to explain it as meaning
JOIN ON TRUE, instead. Per a suggestion from David Johnston.
Tom Lane [Mon, 17 Jul 2017 20:43:03 +0000 (16:43 -0400)]
Doc: explain dollar quoting in the intro part of the pl/pgsql chapter.
We're throwing people into the guts of the syntax with not much context;
let's back up one step and point out that this goes inside a literal in
a CREATE FUNCTION command. Per suggestion from Kurt Kartaltepe.
Tom Lane [Mon, 17 Jul 2017 19:28:17 +0000 (15:28 -0400)]
Merge large_object.sql test into largeobject.source.
It seems pretty confusing to have tests named both largeobject and
large_object. The latter is of very recent vintage (commit ff992c074),
so get rid of it in favor of merging into the former.
Also, enable the LO comment test that was added by commit 70ad7ed4e,
since the later commit added the then-missing pg_upgrade functionality.
The large_object.sql test case is almost completely redundant with that,
but not quite: it seems like creating a user-defined LO with an OID in
the system range might be an interesting case for pg_upgrade, so let's
keep it.
Like the earlier patch, back-patch to all supported branches.
When writing a backup to stdout with pg_basebackup on Windows, put stdout
to binary mode. Any CR bytes in the output will otherwise be output
incorrectly as CR+LF.
In the passing, standardize on using "_setmode" instead of "setmode", for
the sake of consistency. They both do the same thing, but according to
MSDN documentation, setmode is deprecated.
Fixes bug #14634, reported by Henry Boehlert. Patch by Haribabu Kommi.
Backpatch to all supported versions.
Tom Lane [Thu, 13 Jul 2017 23:24:44 +0000 (19:24 -0400)]
Fix dumping of FUNCTION RTEs that contain non-function-call expressions.
The grammar will only accept something syntactically similar to a function
call in a function-in-FROM expression. However, there are various ways
to input something that ruleutils.c won't deparse that way, potentially
leading to a view or rule that fails dump/reload. Fix by inserting a
dummy CAST around anything that isn't going to deparse as a function
(which is one of the ways to get something like that in there in the
first place).
In HEAD, also make use of the infrastructure added by this to avoid
emitting unnecessary parentheses in CREATE INDEX deparsing. I did
not change that in back branches, thinking that people might find it
to be unexpected/unnecessary behavioral change.
In HEAD, also fix incorrect logic for when to add extra parens to
partition key expressions. Somebody apparently thought they could
get away with simpler logic than pg_get_indexdef_worker has, but
they were wrong --- a counterexample is PARTITION BY LIST ((a[1])).
Ignoring the prettyprint flag for partition expressions isn't exactly
a nice solution anyway.
This has been broken all along, so back-patch to all supported branches.
Fix race between GetNewTransactionId and GetOldestActiveTransactionId.
The race condition goes like this:
1. GetNewTransactionId advances nextXid e.g. from 100 to 101
2. GetOldestActiveTransactionId reads the new nextXid, 101
3. GetOldestActiveTransactionId loops through the proc array. There are no
active XIDs there, so it returns 101 as the oldest active XID.
4. GetNewTransactionid stores XID 100 to MyPgXact->xid
So, GetOldestActiveTransactionId returned XID 101, even though 100 only
just started and is surely still running.
This would be hard to hit in practice, and even harder to spot any ill
effect if it happens. GetOldestActiveTransactionId is only used when
creating a checkpoint in a master server, and the race condition can only
happen on an online checkpoint, as there are no backends running during a
shutdown checkpoint. The oldestActiveXid value of an online checkpoint is
only used when starting up a hot standby server, to determine the starting
point where pg_subtrans is initialized from. For the race condition to
happen, there must be no other XIDs in the proc array that would hold back
the oldest-active XID value, which means that the missed XID must be a top
transaction's XID. However, pg_subtrans is not used for top XIDs, so I
believe an off-by-one error is in fact inconsequential. Nevertheless, let's
fix it, as it's clearly wrong and the fix is simple.
This has been wrong ever since hot standby was introduced, so backport to
all supported versions.
Tom Lane [Wed, 12 Jul 2017 22:00:04 +0000 (18:00 -0400)]
Fix ruleutils.c for domain-over-array cases, too.
Further investigation shows that ruleutils isn't quite up to speed either
for cases where we have a domain-over-array: it needs to be prepared to
look past a CoerceToDomain at the top level of field and element
assignments, else it decompiles them incorrectly. Potentially this would
result in failure to dump/reload a rule, if it looked like the one in the
new test case. (I also added a test for EXPLAIN; that output isn't broken,
but clearly we need more test coverage here.)
Like commit b1cb32fb6, this bug is reachable in cases we already support,
so back-patch all the way.
Reduce memory usage of tsvector type analyze function.
compute_tsvector_stats() detoasted and kept in memory every tsvector value
in the sample, but that can be a lot of memory. The original bug report
described a case using over 10 gigabytes, with statistics target of 10000
(the maximum).
To fix, allocate a separate copy of just the lexemes that we keep around,
and free the detoasted tsvector values as we go. This adds some palloc/pfree
overhead, when you have a lot of distinct lexemes in the sample, but it's
better than running out of memory.
Fixes bug #14654 reported by James C. Reviewed by Tom Lane. Backport to
all supported versions.
Tom Lane [Tue, 11 Jul 2017 20:48:59 +0000 (16:48 -0400)]
Fix multiple assignments to a column of a domain type.
We allow INSERT and UPDATE commands to assign to the same column more than
once, as long as the assignments are to subfields or elements rather than
the whole column. However, this failed when the target column was a domain
over array rather than plain array. Fix by teaching process_matched_tle()
to look through CoerceToDomain nodes, and add relevant test cases.
Also add a group of test cases exercising domains over array of composite.
It's doubtless accidental that CREATE DOMAIN allows this case while not
allowing straight domain over composite; but it does, so we'd better make
sure we don't break it. (I could not find any documentation mentioning
either side of that, so no doc changes.)
It's been like this for a long time, so back-patch to all supported
branches.
Tom Lane [Mon, 10 Jul 2017 15:00:09 +0000 (11:00 -0400)]
On Windows, retry process creation if we fail to reserve shared memory.
We've heard occasional reports of backend launch failing because
pgwin32_ReserveSharedMemoryRegion() fails, indicating that something
has already used that address space in the child process. It's not
very clear what, given that we disable ASLR in Windows builds, but
suspicion falls on antivirus products. It'd be better if we didn't
have to disable ASLR, anyway. So let's try to ameliorate the problem
by retrying the process launch after such a failure, up to 100 times.
Patch by me, based on previous work by Amit Kapila and others.
This is a longstanding issue, so back-patch to all supported branches.
Tom Lane [Mon, 10 Jul 2017 04:08:19 +0000 (00:08 -0400)]
Doc: clarify wording about tool requirements in sourcerepo.sgml.
Original wording had confusingly vague antecedent for "they", so replace
that with a more repetitive but clearer formulation. In passing, make the
link to the installation requirements section more specific. Per gripe
from Martin Mai, though this is not the fix he initially proposed.
Tom Lane [Wed, 28 Jun 2017 16:30:16 +0000 (12:30 -0400)]
Second try at fixing tcp_keepalives_idle option on Solaris.
Buildfarm evidence shows that TCP_KEEPALIVE_THRESHOLD doesn't exist
after all on Solaris < 11. This means we need to take positive action to
prevent the TCP_KEEPALIVE code path from being taken on that platform.
I've chosen to limit it with "&& defined(__darwin__)", since it's unclear
that anyone else would follow Apple's precedent of spelling the symbol
that way.
Also, follow a suggestion from Michael Paquier of eliminating code
duplication by defining a couple of intermediate symbols for the
socket option.
In passing, make some effort to reduce the number of translatable messages
by replacing "setsockopt(foo) failed" with "setsockopt(%s) failed", etc,
throughout the affected files. And update relevant documentation so
that it doesn't claim to provide an exhaustive list of the possible
socket option names.
Like the previous commit (f0256c774), back-patch to all supported branches.
Tom Lane [Tue, 27 Jun 2017 22:47:57 +0000 (18:47 -0400)]
Support tcp_keepalives_idle option on Solaris.
Turns out that the socket option for this is named TCP_KEEPALIVE_THRESHOLD,
at least according to the tcp(7P) man page for Solaris 11. (But since that
text refers to "SunOS", it's likely pretty ancient.) It appears that the
symbol TCP_KEEPALIVE does get defined on that platform, but it doesn't
seem to represent a valid protocol-level socket option. This leads to
bleats in the postmaster log, and no tcp_keepalives_idle functionality.
Per bug #14720 from Andrey Lizenko, as well as an earlier report from
Dhiraj Chawla that nobody had followed up on. The issue's been there
since we added the TCP_KEEPALIVE code path in commit 5acd417c8, so
back-patch to all supported branches.
Tom Lane [Mon, 26 Jun 2017 21:31:56 +0000 (17:31 -0400)]
Don't lose walreceiver start requests due to race condition in postmaster.
When a walreceiver dies, the startup process will notice that and send
a PMSIGNAL_START_WALRECEIVER signal to the postmaster, asking for a new
walreceiver to be launched. There's a race condition, which at least
in HEAD is very easy to hit, whereby the postmaster might see that
signal before it processes the SIGCHLD from the walreceiver process.
In that situation, sigusr1_handler() just dropped the start request
on the floor, reasoning that it must be redundant. Eventually, after
10 seconds (WALRCV_STARTUP_TIMEOUT), the startup process would make a
fresh request --- but that's a long time if the connection could have
been re-established almost immediately.
Fix it by setting a state flag inside the postmaster that we won't
clear until we do launch a walreceiver. In cases where that results
in an extra walreceiver launch, it's up to the walreceiver to realize
it's unwanted and go away --- but we have, and need, that logic anyway
for the opposite race case.
I came across this through investigating unexpected delays in the
src/test/recovery TAP tests: it manifests there in test cases where
a master server is stopped and restarted while leaving streaming
slaves active.
This logic has been broken all along, so back-patch to all supported
branches.
Tom Lane [Mon, 26 Jun 2017 20:17:06 +0000 (16:17 -0400)]
Ignore old stats file timestamps when starting the stats collector.
The stats collector disregards inquiry messages that bear a cutoff_time
before when it last wrote the relevant stats file. That's fine, but at
startup when it reads the "permanent" stats files, it absorbed their
timestamps as if they were the times at which the corresponding temporary
stats files had been written. In reality, of course, there's no data
out there at all. This led to disregarding inquiry messages soon after
startup if the postmaster had been shut down and restarted within less
than PGSTAT_STAT_INTERVAL; which is a pretty common scenario, both for
testing and in the field. Requesting backends would hang for 10 seconds
and then report failure to read statistics, unless they got bailed out
by some other backend coming along and making a newer request within
that interval.
I came across this through investigating unexpected delays in the
src/test/recovery TAP tests: it manifests there because the autovacuum
launcher hangs for 10 seconds when it can't get statistics at startup,
thus preventing a second shutdown from occurring promptly. We might
want to do some things in the autovac code to make it less prone to
getting stuck that way, but this change is a good bug fix regardless.
In passing, also fix pgstat_read_statsfiles() to ensure that it
re-zeroes its global stats variables if they are corrupted by a
short read from the stats file. (Other reads in that function
go into temp variables, so that the issue doesn't arise.)
This has been broken since we created the separation between permanent
and temporary stats files in 8.4, so back-patch to all supported branches.
Andres Freund [Wed, 21 Jun 2017 20:51:40 +0000 (13:51 -0700)]
Fix possibility of creating a "phantom" segment after promotion.
When promoting a standby just after a XLOG_SWITCH record was replayed,
and next segment(s) are already are locally available (via walsender,
restore_command + trigger/recovery target), that segment could
accidentally be recycled onto the past of the new timeline. Later
checkpointer would create a .ready file for it, assuming there was an
error during creation, and it would get archived. That causes trouble
if another standby is later brought up from a basebackup from before
the timeline creation, because it would try to read the
segment, because XLogFileReadAnyTLI just tries all possible timelines,
which doesn't have valid contents. Thus replay would fail.
The problem, if already occurred, can be fixed by removing the segment
and/or having restore_command filter it out.
The reason for the creation of such "phantom" segments was, that after
an XLOG_SWITCH record the EndOfLog variable points to the beginning of
the next segment, and RemoveXlogFile() used XLByteToPrevSeg().
Normally RemoveXlogFile() doing so is harmless, because the last
segment will still exist preventing InstallXLogFileSegment() from
causing harm, but just after promotion there's no previous segment on
the new timeline.
Fix that by using XLByteToSeg() instead of XLByteToPrevSeg().
Author: Andres Freund Reported-By: Greg Burek
Discussion: https://postgr.es/m/20170619073026.zcwpe6mydsaz5ygd@alap3.anarazel.de
Backpatch: 9.2-, bug older than all supported versions
Bruce Momjian [Tue, 20 Jun 2017 17:20:02 +0000 (13:20 -0400)]
pg_upgrade: start/stop new server after pg_resetwal
When commit 0f33a719fdbb5d8c43839ea0d2c90cd03e2af2d2 removed the
instructions to start/stop the new cluster before running rsync, it was
now possible for pg_resetwal/pg_resetxlog to leave the final WAL record
at wal_level=minimum, preventing upgraded standby servers from
reconnecting.
This patch fixes that by having pg_upgrade unconditionally start/stop
the new cluster after pg_resetwal/pg_resetxlog has run.
Backpatch through 9.2 since, though the instructions were added in PG
9.5, they worked all the way back to 9.2.
Tom Lane [Mon, 19 Jun 2017 15:02:45 +0000 (11:02 -0400)]
On Windows, make pg_dump use binary mode for compressed plain text output.
The combination of -Z -Fp and output to stdout resulted in corrupted
output data, because we left stdout in text mode, resulting in newline
conversion being done on the compressed stream. Switch stdout to binary
mode for this case, at the same place where we do it for non-text output
formats.
Report and patch by Kuntal Ghosh, tested by Ashutosh Sharma and Neha
Sharma. Back-patch to all supported branches.
Fix dependency, when changing a function's argument/return type.
When a new base type is created using the old-style procedure of first
creating the input/output functions with "opaque" in place of the base
type, the "opaque" argument/return type is changed to the final base type,
on CREATE TYPE. However, we did not create a pg_depend record when doing
that, so the functions were left not depending on the type.
Tom Lane [Thu, 15 Jun 2017 19:03:39 +0000 (15:03 -0400)]
Fix low-probability leaks of PGresult objects in the backend.
We had three occurrences of essentially the same coding pattern
wherein we tried to retrieve a query result from a libpq connection
without blocking. In the case where PQconsumeInput failed (typically
indicating a lost connection), all three loops simply gave up and
returned, forgetting to clear any previously-collected PGresult
object. Since those are malloc'd not palloc'd, the oversight results
in a process-lifespan memory leak.
One instance, in libpqwalreceiver, is of little significance because
the walreceiver process would just quit anyway if its connection fails.
But we might as well fix it.
The other two instances, in postgres_fdw, are somewhat more worrisome
because at least in principle the scenario could be repeated, allowing
the amount of memory leaked to build up to something worth worrying
about. Moreover, in these cases the loops contain CHECK_FOR_INTERRUPTS
calls, as well as other calls that could potentially elog(ERROR),
providing another way to exit without having cleared the PGresult.
Here we need to add PG_TRY logic similar to what exists in quite a
few other places in postgres_fdw.
Coverity noted the libpqwalreceiver bug; I found the other two cases
by checking all calls of PQconsumeInput.
Back-patch to all supported versions as appropriate (9.2 lacks
postgres_fdw, so this is really quite unexciting for that branch).
Tatsuo Ishii [Thu, 15 Jun 2017 01:01:39 +0000 (10:01 +0900)]
Fix document bug regarding read only transactions.
It was explained that read only transactions (not in standby) allow to
update sequences. This had been wrong since the commit: 05d8a561ff85db1545f5768fe8d8dc9d99ad2ef7
Andres Freund [Tue, 6 Jun 2017 01:53:42 +0000 (18:53 -0700)]
Unify SIGHUP handling between normal and walsender backends.
Because walsender and normal backends share the same main loop it's
problematic to have two different flag variables, set in signal
handlers, indicating a pending configuration reload. Only certain
walsender commands reach code paths checking for the
variable (START_[LOGICAL_]REPLICATION, CREATE_REPLICATION_SLOT
... LOGICAL, notably not base backups).
This is a bug present since the introduction of walsender, but has
gotten worse in releases since then which allow walsender to do more.
A later patch, not slated for v10, will similarly unify SIGHUP
handling in other types of processes as well.
Author: Petr Jelinek, Andres Freund Reviewed-By: Michael Paquier
Discussion: https://postgr.es/m/20170423235941.qosiuoyqprq4nu7v@alap3.anarazel.de
Backpatch: 9.2-, bug is present since 9.0
Tom Lane [Thu, 1 Jun 2017 17:32:56 +0000 (13:32 -0400)]
Always use -fPIC, not -fpic, when building shared libraries with gcc.
On some platforms, -fpic fails for sufficiently large shared libraries.
We've mostly not hit that boundary yet, but there are some extensions
such as Citus and pglogical where it's becoming a problem. A bit of
research suggests that the penalty for -fPIC is small, in the
single-digit-percentage range --- and there's none at all on popular
platforms such as x86_64. So let's just default to -fPIC everywhere
and provide one less thing for extension developers to worry about.
Per complaint from Christoph Berg. Back-patch to all supported branches.
(I did not bother to touch the recently-removed Makefiles for sco and
unixware in the back branches, though. We'd have no way to test that
it doesn't break anything on those platforms.)
Tom Lane [Mon, 29 May 2017 21:08:16 +0000 (17:08 -0400)]
Prevent running pg_resetwal/pg_resetxlog against wrong-version data dirs.
pg_resetwal (formerly pg_resetxlog) doesn't insist on finding a matching
version number in pg_control, and that seems like an important thing to
preserve since recovering from corrupt pg_control is a prime reason to
need to run it. However, that means you can try to run it against a
data directory of a different major version, which is at best useless
and at worst disastrous. So as to provide some protection against that
type of pilot error, inspect PG_VERSION at startup and refuse to do
anything if it doesn't match. PG_VERSION is read-only after initdb,
so it's unlikely to get corrupted, and even if it were corrupted it would
be easy to fix by hand.
This hazard has been there all along, so back-patch to all supported
branches.
Tom Lane [Mon, 29 May 2017 19:19:07 +0000 (15:19 -0400)]
Allow NumericOnly to be "+ FCONST".
The NumericOnly grammar production accepted ICONST, + ICONST, - ICONST,
FCONST, and - FCONST, but for some reason not + FCONST. This led to
strange inconsistencies like
regression=# set random_page_cost = +4;
SET
regression=# set random_page_cost = 4000000000;
SET
regression=# set random_page_cost = +4000000000;
ERROR: syntax error at or near "4000000000"
(because 4000000000 is too large to be an ICONST). While there's
no actual functional reason to need to write a "+", if we allow
it for integers it seems like we should allow it for numerics too.
It's been like that forever, so back-patch to all supported branches.
Tom Lane [Fri, 26 May 2017 19:16:59 +0000 (15:16 -0400)]
Move autogenerated array types out of the way during ALTER ... RENAME.
Commit 9aa3c782c added code to allow CREATE TABLE/CREATE TYPE to not fail
when the desired type name conflicts with an autogenerated array type, by
dint of renaming the array type out of the way. But I (tgl) overlooked
that the same case arises in ALTER TABLE/TYPE RENAME. Fix that too.
Back-patch to all supported branches.
Report and patch by Vik Fearing, modified a bit by me
Tom Lane [Fri, 26 May 2017 16:51:06 +0000 (12:51 -0400)]
Fix pg_dump to not emit invalid SQL for an empty operator class.
If an operator class has no operators or functions, and doesn't need
a STORAGE clause, we emitted "CREATE OPERATOR CLASS ... AS ;" which
is syntactically invalid. Fix by forcing a STORAGE clause to be
emitted anyway in this case.
(At some point we might consider changing the grammar to allow CREATE
OPERATOR CLASS without an opclass_item_list. But probably we'd want to
omit the AS in that case, so that wouldn't fix this pg_dump issue anyway.)
It's been like this all along, so back-patch to all supported branches.
Daniel Gustafsson, tweaked by me to avoid a dangling-pointer bug
projects / postgresql / log