The intention in commit 491c029db was to require superuserness to
change the BYPASSRLS property, but the actual effect of the coding
in AlterRole() was to require superuserness to change anything at all
about a BYPASSRLS role. Other properties of a BYPASSRLS role should
be changeable under the same rules as for a normal role, though.
Fix that, and also take care of some documentation omissions related
to BYPASSRLS and REPLICATION role properties.
Tom Lane and Stephen Frost, per bug report from Wolfgang Walther.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/a5548a9f-89ee-3167-129d-162b5985fcf8@technowledgy.de
Although error results received from the backend should always have
a SQLSTATE field, ones generated by libpq won't, making this code
vulnerable to a crash after, say, untimely loss of connection.
Noted by Coverity.
Oversight in commit 403a3d91c. Back-patch to 9.5, as that was.
In almost all other places, we use plain "r" or "w" mode in popen()
calls (the exceptions being for COPY data). This one has been
overlooked (possibly because it's buried in a ".l" flex file?),
but it's using PG_BINARY_R.
Kensuke Okamura complained in bug #16688 that we fail to strip \r
when stripping the trailing newline from a backtick result string.
That's true enough, but we'd also fail to convert embedded \r\n
cleanly, which also seems undesirable. Fixing the popen() mode
seems like the best way to deal with this.
It's been like this for a long time, so back-patch to all supported
branches.
Discussion: https://postgr.es/m/16688-c649c7b69cd7e6f8@postgresql.org
EventTriggerAlterTableEnd neglected to make sure that it built its
output list in the right context. In simple cases this was masked
because the function is called in PortalContext which will be
sufficiently long-lived anyway; but that doesn't make it not a bug.
Commit ced138e8c fixed this in HEAD and v13, but mistakenly chose
not to back-patch further. Back-patch the same code change all
the way (I didn't bother with the test case though, as it would
prove nothing in pre-v13 branches).
Per report from Arseny Sher.
Original fix by Jehan-Guillaume de Rorthais.
Discussion: https://postgr.es/m/877drcyprb.fsf@ars-thinkpad
Discussion: https://postgr.es/m/20200902193715.6e0269d4@firost
Now that LOCK TABLE can take any relation type, acquire lock on all
relations that are to be dumped. This prevents schema changes or
deadlock errors that could cause a dump to fail after expending much
effort. The server is tested to have the capability and the feature
disabled if it doesn't, so that a patched pg_dump doesn't fail when
connecting to an unpatched server.
Backpatch to 9.5.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Wells Oliver <wells.oliver@gmail.com>
Discussion: https://postgr.es/m/20201021200659.GA32358@alvherre.pgsql
The restriction that only tables and views can be locked by LOCK TABLE
is quite arbitrary, since the underlying mechanism can lock any relation
type. Drop the restriction so that programs such as pg_dump can lock
all relations they're interested in, preventing schema changes that
could cause a dump to fail after expending much effort.
Backpatch to 9.5.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Wells Oliver <wells.oliver@gmail.com>
Discussion: https://postgr.es/m/20201021200659.GA32358@alvherre.pgsql
We must not set the "done" flag until after we've executed the
initialization function. Otherwise, other threads can fall through
the initial unlocked test before initialization is really complete.
This has been seen to cause rare failures of ecpg's thread/descriptor
test, and it could presumably cause other sorts of misbehavior in
threaded ECPG-using applications, since ecpglib relies on
pthread_once() in several places.
Diagnosis and patch by me, based on investigation by Alexander Lakhin.
Back-patch to all supported branches (the bug dates to 2007).
Discussion: https://postgr.es/m/16685-d6cd241872c101d3@postgresql.org
There's no functional change at all here, but I'm curious to see
whether this change successfully shuts up Coverity's warning about
a useless strcmp(), which appeared with the previous update.
Discussion: http://mm.icann.org/pipermail/tz/2020-October/029370.html
psql's \connect claims to be able to re-use previous connection
parameters, but in fact it only re-uses the database name, user name,
host name (and possibly hostaddr, depending on version), and port.
This is problematic for assorted use cases. Notably, pg_dump[all]
emits "\connect databasename" commands which we would like to have
re-use all other parameters. If such a script is loaded in a psql run
that initially had "-d connstring" with some non-default parameters,
those other parameters would be lost, potentially causing connection
failure. (Thus, this is the same kind of bug addressed in commits
a45bc8a4f and 8e5793ab6, although the details are much different.)
To fix, redesign do_connect() so that it pulls out all properties
of the old PGconn using PQconninfo(), and then replaces individual
properties in that array. In the case where we don't wish to re-use
anything, get libpq's default settings using PQconndefaults() and
replace entries in that, so that we don't need different code paths
for the two cases.
This does result in an additional behavioral change for cases where
the original connection parameters allowed multiple hosts, say
"psql -h host1,host2", and the \connect request allows re-use of the
host setting. Because the previous coding relied on PQhost(), it
would only permit reconnection to the same host originally selected.
Although one can think of scenarios where that's a good thing, there
are others where it is not. Moreover, that behavior doesn't seem to
meet the principle of least surprise, nor was it documented; nor is
it even clear it was intended, since that coding long pre-dates the
addition of multi-host support to libpq. Hence, this patch is content
to drop it and re-use the host list as given.
Per Peter Eisentraut's comments on bug #16604. Back-patch to all
supported branches.
Discussion: https://postgr.es/m/16604-933f4b8791227b15@postgresql.org
In shm_mq_receive(), a huge payload could trigger an unjustified
"invalid memory alloc request size" error due to the way the buffer
size is increased.
Add error checks (documenting the upper limit) and avoid the error by
limiting the allocation size to MaxAllocSize.
Author: Markus Wanner <markus.wanner@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/3bb363e7-ac04-0ac4-9fe8-db1148755bfa%402ndquadrant.com
When told to process all databases, clusterdb, reindexdb, and vacuumdb
would reconnect by replacing their --maintenance-db parameter with the
name of the target database. If that parameter is a connstring (which
has been allowed for a long time, though we failed to document that
before this patch), we'd lose any other options it might specify, for
example SSL or GSS parameters, possibly resulting in failure to connect.
Thus, this is the same bug as commit a45bc8a4f fixed in pg_dump and
pg_restore. We can fix it in the same way, by using libpq's rules for
handling multiple "dbname" parameters to add the target database name
separately. I chose to apply the same refactoring approach as in that
patch, with a struct to handle the command line parameters that need to
be passed through to connectDatabase. (Maybe someday we can unify the
very similar functions here and in pg_dump/pg_restore.)
Per Peter Eisentraut's comments on bug #16604. Back-patch to all
supported branches.
Discussion: https://postgr.es/m/16604-933f4b8791227b15@postgresql.org
The Windows documentation insists that every WSAStartup call should
have a matching WSACleanup call. However, if that ever had actual
relevance, it wasn't in this century. Every remotely-modern Windows
kernel is capable of cleaning up when a process exits without doing
that, and must be so to avoid resource leaks in case of a process
crash. Moreover, Postgres backends have done WSAStartup without
WSACleanup since commit 4cdf51e64 in 2004, and we've never seen any
indication of a problem with that.
libpq's habit of doing WSAStartup during connection start and
WSACleanup during shutdown is also rather inefficient, since a
series of non-overlapping connection requests leads to repeated,
quite expensive DLL unload/reload cycles. We document a workaround
for that (having the application call WSAStartup for itself), but
that's just a kluge. It's also worth noting that it's far from
uncommon for applications to exit without doing PQfinish, and
we've not heard reports of trouble from that either.
However, the real reason for acting on this is that recent
experiments by Alexander Lakhin show that calling WSACleanup
during PQfinish is triggering the symptom we occasionally see
that a process using libpq fails to emit expected stdio output.
Therefore, let's change libpq so that it calls WSAStartup only
once per process, during the first connection attempt, and never
calls WSACleanup at all.
While at it, get rid of the only other WSACleanup call in our code
tree, in pg_dump/parallel.c; that presumably is equally useless.
Back-patch of HEAD commit 7d00a6b2d.
Discussion: https://postgr.es/m/ac976d8c-03df-d6b8-025c-15a2de8d9af1@postgrespro.ru
In the planner, it was possible, given an extreme enough case containing a
large number of joins for the number of estimated rows to become infinite.
This could cause problems in initial_cost_mergejoin() where we perform
some calculations based on those row estimates.
A problem case, presented by Onder Kalaci showed an Assert failure from
an Assert checking outerstartsel <= outerendsel. In his test case this
was effectively NaN <= Inf, which is false. The NaN outerstartsel came
from multiplying the infinite outer_path_rows by 0.0.
In master, this problem was fixed by a90c950fc, however, that fix was too
invasive for the backbranches. Here we just relax the Asserts to allow
them to pass. The worst that appears to happen from this is that we show
NaN cost values and infinite row estimates in EXPLAIN. add_path() would
have had a hard time doing anything useful with such costs, but that does
not really matter as if the row estimates were even close to accurate,
such plan would not complete this side of the heat death of the universe.
Reported-by: Onder Kalaci
Backpatch: 9.5 to 13
Discussion: https://postgr.es/m/DM6PR21MB1211FF360183BCA901B27F04D80B0@DM6PR21MB1211.namprd21.prod.outlook.com
This changes zic's default output format from "-b fat" to "-b slim".
We were already using "slim" in v13/HEAD, so those branches drop
the explicit -b switch in the Makefiles. Instead, add an explicit
"-b fat" in v12 and before, so that we don't change the output file
format in those branches. (This is perhaps excessively conservative,
but we decided not to do so in a12079109, and I'll stick with that.)
Other non-cosmetic changes are to drop support for zic's long-obsolete
"-y" switch, and to ensure that strftime() does not change errno
unless it fails.
As usual with tzcode changes, back-patch to all supported branches.
This commit required support for inline variable definition, which is
not a requirement.
RELEASE NOTE AUTHOR: the author of commit 3c0471b5fd
(pg_upgrade/tablespaces) was Justin Pryzby, not me.
Reported-by: Andres Freund
Discussion: https://postgr.es/m/20201016001959.h24fkywfubkv2pc5@alap3.anarazel.de
Backpatch-through: 9.5
Previously, if pg_upgrade failed, and the user recreated the cluster but
did not remove the new cluster tablespace directory, a later pg_upgrade
would fail since the new tablespace directory would already exists.
This adds error reporting for this during check.
Reported-by: Justin Pryzby
Discussion: https://postgr.es/m/20200925005531.GJ23631@telsasoft.com
Backpatch-through: 9.5
POSIX sigaction(2) can be told to block a set of signals while a
signal handler executes. Make use of that instead of manually
blocking and unblocking signals in the postmaster's signal handlers.
This should save a few cycles, but more importantly it prevents
recursive invocation of signal handlers when many signals arrive in
close succession. (Assuming that the platform's signal infrastructure
is designed to avoid consuming stack space in that case, but this is
demonstrably true at least on Linux.) The existing code has been seen
to recurse to the point of stack overflow, either in the postmaster
or in a forked-off child.
Back-patch of commit 9abb2bfc0. At the time, we'd only seen excess
postmaster stack consumption in the buildfarm; but we now have a
user report of it, and that commit has aged enough to have a fair
amount of confidence that it doesn't break anything.
This still doesn't change anything about the way that it works on
Windows. Perhaps someone else would like to fix that?
Per bug #16673 from David Geier. Back-patch to 9.6. Although
the problem exists in principle before that, we've only seen it
actually materialize in connection with heavy use of parallel
workers, so it doesn't seem necessary to do anything in 9.5;
and the relevant code is different there, too.
Discussion: https://postgr.es/m/16673-d278c604f8e34ec0@postgresql.org
Discussion: https://postgr.es/m/14878.1570820201@sss.pgh.pa.us
The prohibitValueChange code paths in set_config_option(), which
are executed whenever we re-read a PGC_POSTMASTER variable from
postgresql.conf, neglected to free anything before exiting. Thus
we'd leak the proposed new value of a PGC_STRING variable, as noted
by BoChen in bug #16666. For all variable types, if the check hook
creates an "extra" chunk, we'd also leak that.
These are malloc not palloc chunks, so there is no mechanism for
recovering the leaks before process exit. Fortunately, the values
are typically not very large, meaning you'd have to go through an
awful lot of SIGHUP configuration-reload cycles to make the leakage
amount to anything. Still, for a long-lived postmaster process it
could potentially be a problem.
Oversight in commit 2594cf0e8. Back-patch to all supported branches.
Discussion: https://postgr.es/m/16666-2c41a4eec61b03e1@postgresql.org
It appears that commit cf63c641c, which intended to prevent
misoptimization of the result-building step in makeOrderedSetArgs,
didn't go far enough: buildfarm member hornet's version of xlc
is now optimizing back to the old, broken behavior in which
list_length(directargs) is fetched only after list_concat() has
changed that value. I'm not entirely convinced whether that's
an undeniable compiler bug or whether it can be justified by a
sufficiently aggressive interpretation of C sequence points.
So let's just change the code to make it harder to misinterpret.
Back-patch to all supported versions, just in case.
Discussion: https://postgr.es/m/1830491.1601944935@sss.pgh.pa.us
Commit 3eb3d3e78 was a few bricks shy of a load: while it correctly
set the table's "interesting" flag when deciding to dump the data of
an extension config table, it was not correct to clear that flag
if we concluded we shouldn't dump the data. This led to the crash
reported in bug #16655, because in fact we'll traverse dumpTableSchema
anyway for all extension tables (to see if they have user-added
seclabels or RLS policies).
The right thing to do is to force "interesting" true in makeTableDataInfo,
and otherwise leave the flag alone. (Doing it there is more future-proof
in case additional calls are added, and it also avoids setting the flag
unnecessarily if that function decides the table is non-dumpable.)
This investigation also showed that while only the --inserts code path
had an obvious failure in the case considered by 3eb3d3e78, the COPY
code path also has a problem with not having loaded table subsidiary
data. That causes fmtCopyColumnList to silently return an empty string
instead of the correct column list. That accidentally mostly works,
which perhaps is why we didn't notice this before. It would only fail
if the restore column order is different from the dump column order,
which only happens in weird inheritance cases, so it's not surprising
nobody had hit the case with an extension config table. Nonetheless,
it's a bug, and it goes a long way back, not just to v12 where the
--inserts code path started to have a problem with this.
In hopes of catching such cases a bit sooner in future, add some
Asserts that "interesting" has been set in both dumpTableData and
dumpTableSchema. Adjust the test case added by 3eb3d3e78 so that it
checks the COPY rather than INSERT form of that bug, allowing it to
detect the longer-standing symptom.
Per bug #16655 from Cameron Daniel. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/16655-5c92d6b3a9438137@postgresql.org
Discussion: https://postgr.es/m/18048b44-3414-b983-8c7c-9165b177900d@2ndQuadrant.com
get_eclass_for_sort_expr() computes expr_relids and nullable_relids
early on, even though they won't be needed unless we make a new
EquivalenceClass, which we often don't. Aside from the probably-minor
inefficiency, there's a memory management problem: these bitmapsets will
be built in the caller's context, leading to dangling pointers if that
is shorter-lived than root->planner_cxt. This would be a live bug if
get_eclass_for_sort_expr() could be called with create_it = true during
GEQO join planning. So far as I can find, the core code never does
that, but it's hard to be sure that no extensions do, especially since
the comments make it clear that that's supposed to be a supported case.
Fix by not computing these values until we've switched into planner_cxt
to build the new EquivalenceClass.
generate_join_implied_equalities() uses inner_rel->relids to look up
relevant eclasses, but it ought to be using nominal_inner_relids.
This is presently harmless because a child RelOptInfo will always have
exactly the same eclass_indexes as its topmost parent; but that might
not be true forever, and anyway it makes the code confusing.
The first of these is old (introduced by me in f3b3b8d5b), so back-patch
to all supported branches. The second only dates to v13, but we might
as well back-patch it to keep the code looking similar across branches.
Discussion: https://postgr.es/m/1508010.1601832581@sss.pgh.pa.us
Previously, a conversion such as
to_date('-44-02-01','YYYY-MM-DD')
would result in '0045-02-01 BC', as the code attempted to interpret
the negative year as BC, but failed to apply the correction needed
for our internal handling of BC years. Fix the off-by-one problem.
Also, arrange for the combination of a negative year and an
explicit "BC" marker to cancel out and produce AD. This is how
the negative-century case works, so it seems sane to do likewise.
Continue to read "year 0000" as 1 BC. Oracle would throw an error,
but we've accepted that case for a long time so I'm hesitant to
change it in a back-patch.
Per bug #16419 from Saeed Hubaishan. Back-patch to all supported
branches.
Dar Alathar-Yemen and Tom Lane
Discussion: https://postgr.es/m/16419-d8d9db0a7553f01b@postgresql.org
Previously the standby server didn't archive timeline history files
streamed from the primary even when archive_mode is set to "always",
while it archives the streamed WAL files. This could cause the PITR to
fail because there was no required timeline history file in the archive.
The cause of this issue was that walreceiver didn't mark those files as
ready for archiving.
This commit makes walreceiver mark those streamed timeline history
files as ready for archiving if archive_mode=always. Then the archiver
process archives the marked timeline history files.
Back-patch to all supported versions.
Reported-by: Grigory Smolkin
Author: Grigory Smolkin, Fujii Masao
Reviewed-by: David Zhang, Anastasia Lubennikova
Discussion: https://postgr.es/m/54b059d4-2b48-13a4-6f43-95a087c92367@postgrespro.ru
This function leaked some memory while loading qual clauses for
an RLS policy. While ordinarily negligible, that could build up
in some repeated-reload cases, as reported by Konstantin Knizhnik.
We can improve matters by borrowing the coding long used in
RelationBuildRuleLock: build stringToNode's result directly in
the target context, and remember to explicitly pfree the
input string.
This patch by no means completely guarantees zero leaks within
this function, since we have no real guarantee that the catalog-
reading subroutines it calls don't leak anything. However,
practical tests suggest that this is enough to resolve the issue.
In any case, any remaining leaks are similar to those risked by
RelationBuildRuleLock and other relcache-loading subroutines.
If we need to fix them, we should adopt a more global approach
such as that used by the RECOVER_RELATION_BUILD_MEMORY hack.
While here, let's remove the need for an expensive PG_TRY block by
using MemoryContextSetParent to reparent an initially-short-lived
context for the RLS data.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/21356c12-8917-8249-b35f-1c447231922b@postgrespro.ru
Parallel pg_dump failed if its -d parameter was a connection string
containing any essential information other than host, port, or username.
The same was true for pg_restore with --create.
The reason is that these scenarios failed to preserve the connection
string from the command line; the code felt free to replace that with
just the database name when reconnecting from a pg_dump parallel worker
or after creating the target database. By chance, parallel pg_restore
did not suffer this defect, as long as you didn't say --create.
In practice it seems that the error would be obvious only if the
connstring included essential, non-default SSL or GSS parameters.
This may explain why it took us so long to notice. (It also makes
it very difficult to craft a regression test case illustrating the
problem, since the test would fail in builds without those options.)
Fix by refactoring so that ConnectDatabase always receives all the
relevant options directly from the command line, rather than
reconstructed values. Inject a different database name, when necessary,
by relying on libpq's rules for handling multiple "dbname" parameters.
While here, let's get rid of the essentially duplicate _connectDB
function, as well as some obsolete nearby cruft.
Per bug #16604 from Zsolt Ero. Back-patch to all supported branches.
Discussion: https://postgr.es/m/16604-933f4b8791227b15@postgresql.org
Harmonize behavior by moving reponsibility for fsyncing directories down
into slru.c. In 10 and later, only the multixact directories were
missed (see commit 1b02be21), and in older branches all SLRUs were
missed.
Back-patch to all supported releases.
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CA%2BhUKGLtsTUOScnNoSMZ-2ZLv%2BwGh01J6kAo_DM8mTRq1sKdSQ%40mail.gmail.com
tsearch_readline() saves the string pointer it returns to the caller
for possible use in the associated error context callback. However,
the caller will usually pfree that string sometime before it next
calls tsearch_readline(), so that there is a window where an ereport
will try to print an already-freed string.
The built-in users of tsearch_readline() happen to all do that pfree
at the bottoms of their loops, so that the window is effectively
empty for them. However, this is not documented as a requirement,
and contrib/dict_xsyn doesn't do it like that, so it seems likely
that third-party dictionaries might have live bugs here.
The practical consequences of this seem pretty limited in any case,
since production builds wouldn't clobber the freed string immediately,
besides which you'd not expect syntax errors in dictionary files
being used in production. Still, it's clearly a bug waiting to bite
somebody.
Fix by pstrdup'ing the string to be saved for the error callback,
and then pfree'ing it next time through. It's been like this for
a long time, so back-patch to all supported branches.
Discussion: https://postgr.es/m/48A4FA71-524E-41B9-953A-FD04EF36E2E7@yesql.se
These two SQL functions are aliases for the same C function, so this
change has no semantic effect. However, because we dropped the
numeric_fac alias in HEAD (commit 76f412ab3), operator definitions
based on that one don't port forward, causing problems for cross-version
upgrade tests based on the regression database.
Patch all active back branches to dodge the problem.
Discussion: https://postgr.es/m/449144.1600439950@sss.pgh.pa.us
The test failed when something added WAL between pg_switch_wal() and
pg_current_wal_lsn(), seen on buildfarm members hornet and sungazer.
Fix v10, v9.6 and v9.5 by making this code mirror its v13+ counterpart.
v12 and v11 lack a counterpart.
transformCreateStmt() adjusts the transformed statement's RangeVar
to specify the target schema explicitly, for the express reason
of making sure that auxiliary statements derived by parse
transformation operate on the right table. But the refactoring
I did in commit 502898192 got this wrong and passed the untransformed
RangeVar to expandTableLikeClause(). This could lead to assertion
failures or weird misbehavior if the wrong table was accessed.
Per report from Alexander Lakhin. Like the previous patch, back-patch
to all supported branches.
Discussion: https://postgr.es/m/05051f9d-b32b-cb35-6735-0e9f2ab86b5f@gmail.com
Bring the signal handling for startup-packet collection into line
with the policy established in commits bedadc732 and 8e19a8264,
namely don't risk running atexit callbacks when handling SIGQUIT.
Ideally, we'd not do so for SIGTERM or timeout interrupts either,
but that change seems a bit too risky for the back branches.
For now, just improve the comments in this area to describe the risk.
Also relocate where BackendInitialize re-disables these interrupts,
to minimize the code span where they're active. This doesn't buy
a whole lot of safety, but it can't hurt.
In passing, rename startup_die() to remove confusion about whether
it is for the startup process.
Like the previous commits, back-patch to all supported branches.
Discussion: https://postgr.es/m/1850884.1599601164@sss.pgh.pa.us
Commit 8e19a8264 changed the SIGQUIT handlers of almost all server
processes not to run atexit callbacks. The archiver process was
skipped, perhaps because it's not connected to shared memory; but
it's just as true here that running atexit callbacks in a signal
handler is unsafe. So let's make it work like the rest.
In HEAD and v13, we can use the common SignalHandlerForCrashExit
handler. Before that, just tweak pgarch_exit to use _exit(2)
explicitly.
Like the previous commit, back-patch to all supported branches.
Kyotaro Horiguchi, back-patching by me
Discussion: https://postgr.es/m/1850884.1599601164@sss.pgh.pa.us
We reported the wrong types when complaining that an aggregate's
moving-aggregate implementation is inconsistent with its regular
implementation.
This was wrong since the feature was introduced, so back-patch
to all supported branches.
Jeff Janes
Discussion: https://postgr.es/m/CAMkU=1x808LH=LPhZp9mNSP0Xd1xDqEd+XeGcvEe48dfE6xV=A@mail.gmail.com
This is duplicative of an lstat that was just done by the calling
function (traverse_datadir), besides which we weren't really doing
anything with the results. There's not much point in checking to
see if someone removed the file since the previous lstat, since the
FILE_ACTION_REMOVE code would have to deal with missing-file cases
anyway. Moreover, the "exists = false" assignment was a dead store;
nothing was done with that value later.
A syscall saved is a syscall earned, so back-patch to 9.5
where this code was introduced.
Discussion: https://postgr.es/m/1221796.1599329320@sss.pgh.pa.us
The "DROP ACCESS METHOD gist2" test will require locking the index
to be dropped and then its table; while most ordinary operations
lock a table first then its index. While no concurrent test scripts
should be touching fast_emp4000, autovacuum might chance to be
processing that table when the DROP runs, resulting in a deadlock
failure. This is pretty rare but we see it in the buildfarm from
time to time.
To fix, acquire a lock on fast_emp4000 before issuing the DROP.
Since the point of the exercise is mostly to prevent buildfarm
failures, back-patch to 9.6 where this test was introduced.
Discussion: https://postgr.es/m/839004.1599185607@sss.pgh.pa.us
Because sigsetjmp() will restore the initial state with signals blocked,
the code path in bgworker.c for reporting an error and exiting would
execute that way. Usually this is fairly harmless; but if a parallel
worker had an error message exceeding the shared-memory communication
buffer size (16K) it would lock up, because it would wait for a
resume-sending signal from its parallel leader which it would never
detect.
To fix, just unblock signals at the appropriate point.
This can be shown to fail back to 9.6. The lack of parallel query
infrastructure makes it difficult to provide a simple test case for
9.5; but I'm pretty sure the issue exists in some form there as well,
so apply the code change there too.
Vignesh C, reviewed by Bharath Rupireddy, Robert Haas, and myself
Discussion: https://postgr.es/m/CALDaNm1d1hHPZUg3xU4XjtWBOLCrA+-2cJcLpw-cePZ=GgDVfA@mail.gmail.com
Historically there's been a hard-wired assumption here that no line of
a .pgpass file could be as long as NAMEDATALEN*5 bytes. That's a bit
shaky to start off with, because (a) there's no reason to suppose that
host names fit in NAMEDATALEN, and (b) this figure fails to allow for
backslash escape characters. However, it fails completely if someone
wants to use a very long password, and we're now hearing reports of
people wanting to use "security tokens" that can run up to several
hundred bytes. Another angle is that the file is specified to allow
comment lines, but there's no reason to assume that long comment lines
aren't possible.
Rather than guessing at what might be a more suitable limit, let's
replace the fixed-size buffer with an expansible PQExpBuffer. That
adds one malloc/free cycle to the typical use-case, but that's surely
pretty cheap relative to the I/O this code has to do.
Also, add TAP test cases to exercise this code, because there was no
test coverage before.
This reverts most of commit 2eb3bc588, as there's no longer a need for
a warning message about overlength .pgpass lines. (I kept the explicit
check for comment lines, though.)
In HEAD and v13, this also fixes an oversight in 74a308cf5: there's not
much point in explicit_bzero'ing the line buffer if we only do so in two
of the three exit paths.
Back-patch to all supported branches, except that the test case only
goes back to v10 where src/test/authentication/ was added.
Discussion: https://postgr.es/m/4187382.1598909041@sss.pgh.pa.us
collectMatchBitmap() needs to re-find the index tuple it was previously
looking at, after transiently dropping lock on the index page it's on.
The tuple should still exist and be at its prior position or somewhere
to the right of that, since ginvacuum never removes tuples but
concurrent insertions could add one. However, there was a thinko in
that logic, to the effect of expecting any inserted tuples to have the
same index "attnum" as what we'd been scanning. Since there's no
physical separation of tuples with different attnums, it's not terribly
hard to devise scenarios where this fails, leading to transient "lost
saved point in index" errors. (While I've duplicated this with manual
testing, it seems impossible to make a reproducible test case with our
available testing technology.)
Fix by just continuing the scan when the attnum doesn't match.
While here, improve the error message used if we do fail, so that it
matches the wording used in btree for a similar case.
collectMatchBitmap()'s posting-tree code path was previously not
exercised at all by our regression tests. While I can't make
a regression test that exhibits the bug, I can at least improve
the code coverage here, so do that. The test case I made for this
is an extension of one added by 4b754d6c1, so it only works in
HEAD and v13; didn't seem worth trying hard to back-patch it.
Per bug #16595 from Jesse Kinkead. This has been broken since
multicolumn capability was added to GIN (commit 27cb66fdf),
so back-patch to all supported branches.
Discussion: https://postgr.es/m/16595-633118be8eef9ce2@postgresql.org
The trouble with doing this is that an apparently-constant subquery
output column isn't really constant if it is a grouping column that
appears in only some of the grouping sets. A qual using such a
column would be subject to incorrect const-folding after push-down,
as seen in bug #16585 from Paul Sivash.
To fix, just disable qual pushdown altogether if the sub-query has
nonempty groupingSets. While we could imagine far less restrictive
solutions, there is not much point in working harder right now,
because subquery_planner() won't move HAVING clauses to WHERE within
such a subquery. If the qual stays in HAVING it's not going to be
a lot more useful than if we'd kept it at the outer level.
Having said that, this restriction could be removed if we used a
parsetree representation that distinguished such outputs from actual
constants, which is something I hope to do in future. Hence, make
the patch a minimal addition rather than integrating it more tightly
(e.g. by renumbering the existing items in subquery_is_pushdown_safe's
comment).
Back-patch to 9.5 where grouping sets were introduced.
Discussion: https://postgr.es/m/16585-9d8c340d23ade8c1@postgresql.org
If a CREATE TABLE command uses both LIKE and traditional inheritance,
Vars in CHECK constraints and expression indexes that are absorbed
from a LIKE parent table tended to get mis-numbered, resulting in
wrong answers and/or bizarre error messages (though probably not any
actual crashes, thanks to validation occurring in the executor).
In v12 and up, the same could happen to Vars in GENERATED expressions,
even in cases with no LIKE clause but multiple traditional-inheritance
parents.
The cause of the problem for LIKE is that parse_utilcmd.c supposed
it could renumber such Vars correctly during transformCreateStmt(),
which it cannot since we have not yet accounted for columns added via
inheritance. Fix that by postponing processing of LIKE INCLUDING
CONSTRAINTS, DEFAULTS, GENERATED, INDEXES till after we've performed
DefineRelation().
The error with GENERATED and multiple inheritance is a simple oversight
in MergeAttributes(); it knows it has to renumber Vars in inherited
CHECK constraints, but forgot to apply the same processing to inherited
GENERATED expressions (a/k/a defaults).
Per bug #16272 from Tom Gottfried. The non-GENERATED variants of the
issue are ancient, presumably dating right back to the addition of
CREATE TABLE LIKE; hence back-patch to all supported branches.
Discussion: https://postgr.es/m/16272-6e32da020e9a9381@postgresql.org
