Commit Graph

47679 Commits

Author SHA1 Message Date
Peter Geoghegan f01fd89b15 Make check_usermap() parameter names consistent.
The function has a bool argument named "case_insensitive", but that was
spelled "case_sensitive" in the declaration.  Make them consistent now
to avoid confusion in the future.

Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Michael Paquiër <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
Backpatch: 10-
2022-09-17 16:54:08 -07:00
Tom Lane 7391ab28a6 Improve plpgsql's ability to handle arguments declared as RECORD.
Treat arguments declared as RECORD as if that were a polymorphic type
(which it is, sort of), in that we substitute the actual argument type
while forming the function cache lookup key.  This allows the specific
composite type to be known in some cases where it was not before,
at the cost of making a separate function cache entry for each named
composite type that's passed to the function during a session.  The
particular symptom discussed in bug #17610 could be solved in other
more-efficient ways, but only at the cost of considerable development
work, and there are other cases where we'd still fail without this.

Per bug #17610 from Martin Jurča.  Back-patch to v11 where we first
allowed plpgsql functions to be declared as taking type RECORD.

Discussion: https://postgr.es/m/17610-fb1eef75bf6c2364@postgresql.org
2022-09-16 13:23:01 -04:00
Tom Lane 19bb5e46b9 In back branches, fix conditions for pullup of FROM-less subqueries.
In branches before commit 4be058fe9, we have to prevent flattening
of subqueries with empty jointrees if the subqueries' output
columns might need to be wrapped in PlaceHolderVars.  That's
because the empty jointree would result in empty phrels for the
PlaceHolderVars, meaning we'd be unable to figure out where to
evaluate them.  However, we've failed to keep is_simple_subquery's
check for this hazard in sync with what pull_up_simple_subquery
actually does.  The former is checking "lowest_outer_join != NULL",
whereas the conditions pull_up_simple_subquery actually uses are

	if (lowest_nulling_outer_join != NULL)
	if (containing_appendrel != NULL)
	if (parse->groupingSets)

So the outer-join test is overly conservative, while we missed out
checking for appendrels and groupingSets.  The appendrel omission
is harmless, because in that case we also check is_safe_append_member
which will also reject such subqueries.  The groupingSets omission
is a bug though, leading to assertion failures or planner errors
such as "variable not found in subplan target lists".

is_simple_subquery has access to none of the three variables used
in the correct tests, but its callers do, so I chose to have them
pass down a bool corresponding to the OR of these conditions.
(The need for duplicative conditions would be a maintenance
hazard in actively-developed code, but I'm not too concerned
about it in branches that have only ~ 1 year to live.)

Per bug #17614 from Wei Wei.  Patch v10 and v11 only, since we have a
better answer to this in v12 and later (indeed, the faulty check in
is_simple_subquery is gone entirely).

Discussion: https://postgr.es/m/17614-8ec20c85bdecaa2a@postgresql.org
2022-09-15 15:21:35 -04:00
Etsuro Fujita 07d81d1e5b postgres_fdw: Avoid 'variable not found in subplan target list' error.
The tlist of the EvalPlanQual outer plan for a ForeignScan node is
adjusted to produce a tuple whose descriptor matches the scan tuple slot
for the ForeignScan node.  But in the case where the outer plan contains
an extra Sort node, if the new tlist contained columns required only for
evaluating PlaceHolderVars or columns required only for evaluating local
conditions, this would cause setrefs.c to fail with the error.

The cause of this is that when creating the outer plan by injecting the
Sort node into an alternative local join plan that could emit such extra
columns as well, we fail to arrange for the outer plan to propagate them
up through the Sort node, causing setrefs.c to fail to match up them in
the new tlist to what is available from the outer plan.  Repair.

Per report from Alexander Pyhalov.

Richard Guo and Etsuro Fujita, reviewed by Alexander Pyhalov and Tom Lane.
Backpatch to all supported versions.

Discussion: http://postgr.es/m/cfb17bf6dfdf876467bd5ef533852d18%40postgrespro.ru
2022-09-14 18:45:07 +09:00
Michael Paquier f01cc02259 Fix incorrect value for "strategy" with deflateParams() in walmethods.c
The zlib documentation mentions the values supported for the compression
strategy, but this code has been using a hardcoded value of 0 rather
than Z_DEFAULT_STRATEGY.  This commit adjusts the code to use
Z_DEFAULT_STRATEGY.

Backpatch down to where this code has been added to ease the backport of
any future patch touching this area.

Reported-by: Tom Lane
Discussion: https://postgr.es/m/1400032.1662217889@sss.pgh.pa.us
Backpatch-through: 10
2022-09-14 14:52:35 +09:00
Peter Eisentraut e962235fe1 Expand palloc/pg_malloc API for more type safety
This adds additional variants of palloc, pg_malloc, etc. that
encapsulate common usage patterns and provide more type safety.

Specifically, this adds palloc_object(), palloc_array(), and
repalloc_array(), which take the type name of the object to be
allocated as its first argument and cast the return as a pointer to
that type.  There are also palloc0_object() and palloc0_array()
variants for initializing with zero, and pg_malloc_*() variants of all
of the above.

Inspired by the talloc library.

This is backpatched from master so that future backpatchable code can
make use of these APIs.  This patch by itself does not contain any
users of these APIs.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/bb755632-2a43-d523-36f8-a1e7a389a907@enterprisedb.com
2022-09-14 06:08:56 +02:00
Daniel Gustafsson 7b523c543a doc: Fix link to FreeBSD documentation project
The FreeBSD site was changed with a redirect, which in turn seems to
lead to a 404. Replace with the working link.

Author: James Coleman <jtc331@gmail.com>
Discussion: https://postgr.es/m/CAAaqYe_JZRj+KPn=hACtwsg1iLRYs=jYvxG1NW4AnDeUL1GD-Q@mail.gmail.com
2022-09-12 22:17:17 +02:00
Tom Lane fe4e151d4a Fix possible omission of variable storage markers in ECPG.
The ECPG preprocessor converted code such as

static varchar str1[10], str2[20], str3[30];

into

static  struct varchar_1  { int len; char arr[ 10 ]; }  str1 ;
        struct varchar_2  { int len; char arr[ 20 ]; }  str2 ;
        struct varchar_3  { int len; char arr[ 30 ]; }  str3 ;

thus losing the storage attribute for the later variables.
Repeat the declaration for each such variable.

(Note that this occurred only for variables declared "varchar"
or "bytea", which may help explain how it escaped detection
for so long.)

Andrey Sokolov

Discussion: https://postgr.es/m/942241662288242@mail.yandex.ru
2022-09-09 15:34:04 -04:00
Tom Lane 4d3f54bd7a Reject bogus output from uuid_create(3).
When using the BSD UUID functions, contrib/uuid-ossp expects
uuid_create() to produce a version-1 UUID.  FreeBSD still does so,
but in recent NetBSD releases that function produces a version-4
(random) UUID instead.  That's not acceptable for our purposes:
if the user wanted v4 she would have asked for v4, not v1.
Hence, check the version digit and complain if it's not '1'.

Also drop the documentation's claim that the NetBSD implementation
is usable.  It might be, depending on which OS version you're using,
but we're not going to get into that kind of detail.

(Maybe someday we should ditch all these external libraries
and just write our own UUID code, but today is not that day.)

Nazir Bilal Yavuz, with cosmetic adjustments and docs by me.
Backpatch to all supported versions.

Discussion: https://postgr.es/m/3848059.1661038772@sss.pgh.pa.us
Discussion: https://postgr.es/m/17358-89806e7420797025@postgresql.org
2022-09-09 12:41:36 -04:00
Tom Lane 9bcf6fb281 Further fixes for MULTIEXPR_SUBLINK fix.
Some more things I didn't think about in commits 3f7323cbb et al:

MULTIEXPR_SUBLINK subplans might have been converted to initplans
instead of regular subplans, in which case they won't show up in
the modified targetlist.  Fortunately, this would only happen if
they have no input parameters, which means that the problem we
originally needed to fix can't happen with them.  Therefore, there's
no need to clone their output parameters, and thus it doesn't hurt
that we'll fail to see them in the first pass over the targetlist.
Nonetheless, this complicates matters greatly, because now we have
to distinguish output Params of initplans (which shouldn't get
renumbered) from those of regular subplans (which should).
This also breaks the simplistic scheme I used of assuming that the
subplans found in the targetlist have consecutive subLinkIds.
We really can't avoid the need to know the subplans' subLinkIds in
this code.  To fix that, add subLinkId as the last field of SubPlan.
We can get away with that change in back branches because SubPlan
nodes will never be stored in the catalogs, and there's no ABI
break for external code that might be looking at the existing
fields of SubPlan.

Secondly, rewriteTargetListIU might have rolled up multiple
FieldStores or SubscriptingRefs into one targetlist entry,
breaking the assumption that there's at most one Param to fix
per targetlist entry.  (That assumption is OK I think in the
ruleutils.c code I stole the logic from in 18f51083c, because
that only deals with pre-rewrite query trees.  But it's
definitely not OK here.)  Abandon that shortcut and just do a
full tree walk on the targetlist to ensure we find all the
Params we have to change.

Per bug #17606 from Andre Lin.  As before, only v10-v13 need the
patch.

Discussion: https://postgr.es/m/17606-e5c8ad18d31db96a@postgresql.org
2022-09-06 16:38:18 -04:00
Peter Geoghegan a228cca46d Backpatch nbtree page deletion hardening.
Postgres 14 commit 5b861baa taught nbtree VACUUM to tolerate buggy
opclasses.  VACUUM's inability to locate a to-be-deleted page's downlink
in the parent page was logged instead of throwing an error.  VACUUM
could just press on with vacuuming the index, and vacuuming the table as
a whole.

There are now anecdotal reports of this error causing problems that were
much more disruptive than the underlying index corruption ever could be.
Anything that makes VACUUM unable to make forward progress against one
table/index ultimately risks making the system enter xidStopLimit mode.
There is no good reason to take any chances here, so backpatch the
hardening commit.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wzm9HR6Pow=t-iQa57zT8qmX6_M4h14F-pTtb=xFDW5FBA@mail.gmail.com
Backpatch: 10-13 (all supported versions that lacked the hardening)
2022-09-05 11:20:01 -07:00
David Rowley 1630cad740 Doc: clarify partitioned table limitations
Improve documentation regarding the limitations of unique and primary key
constraints on partitioned tables.  The existing documentation didn't make
it clear that the constraint columns had to be present in the partition
key as bare columns.  The reader could be led to believe that it was ok to
include the constraint columns as part of a function call's parameters or
as part of an expression.  Additionally, the documentation didn't mention
anything about the fact that we disallow unique and primary key
constraints if the partition keys contain *any* function calls or
expressions, regardless of if the constraint columns appear as columns
elsewhere in the partition key.

The confusion here was highlighted by a report on the general mailing list
by James Vanns.

Discussion: https://postgr.es/m/CAH7vdhNF0EdYZz3GLpgE3RSJLwWLhEk7A_fiKS9dPBT3Dz_3eA@mail.gmail.com
Discussion: https://postgr.es/m/CAApHDvoU-u9iTqKjteYRFfi+UNEk7dbSAcyxEQD==vZt9B1KnA@mail.gmail.com
Reviewed-by: Erik Rijkers
Backpatch-through: 11
2022-09-05 18:45:43 +12:00
Bruce Momjian 4dc98b4147 doc: simplify docs about analyze and inheritance/partitions
Discussion: https://postgr.es/m/YxAqYijOsLzgLQgy@momjian.us

Backpatch-through: 10
2022-09-02 23:32:18 -04:00
Bruce Momjian 1525711588 doc: clarify recursion internal behavior
Reported-by: Drew DeVault

Discussion: https://postgr.es/m/20211018091720.31299-1-sir@cmpwn.com

Backpatch-through: 10
2022-09-02 21:57:41 -04:00
Tom Lane 56dc442447 Fix oversight in recent MULTIEXPR_SUBLINK fix.
Commits 3f7323cbb et al missed the possibility that the Params
they are looking for could be buried under implicit coercions,
as well as other stuff that processIndirection() could add to
the original targetlist entry.  Copy the code in ruleutils.c
that deals with such cases.  (I thought about refactoring so
that there's just one copy; but seeing that we only need this
in old back branches, it seems not worth the trouble.)

Per off-list report from Andre Lin.  As before, only v10-v13
need the patch.

Discussion: https://postgr.es/m/17596-c5357f61427a81dc@postgresql.org
2022-09-02 14:54:40 -04:00
David Rowley 1b11543967 Fix some possibly latent bugs in slab.c
Primarily, this fixes an incorrect calculation in SlabCheck which was
looking in the wrong byte for the sentinel check.  The reason that we've
never noticed this before in the form of a failing sentinel check is
because the pre-check to this always fails because all current core users
of slab contexts have a chunk size which is already MAXALIGNed, therefore
there's never any space for the sentinel byte.  It is possible that an
extension needs to use a slab context and if they do with a chunk size
that's not MAXALIGNed, then they'll likely get errors about overwritten
sentinel bytes.

Additionally, this patch changes various calculations which are being done
based on the sizeof(SlabBlock).  Currently, sizeof(SlabBlock) is a
multiple of 8, therefore sizeof(SlabBlock) is the same as
MAXALIGN(sizeof(SlabBlock)), however, if we were to ever have to add any
fields to that struct as part of a bug fix, then SlabAlloc could end up
returning a non-MAXALIGNed pointer.  To be safe, let's ensure we always
MAXALIGN sizeof(SlabBlock) before using it in any calculations.

This patch has already been applied to master in d5ee4db0e.

Diagnosed-by: Tomas Vondra, Tom Lane
Author: Tomas Vondra, David Rowley
Discussion: https://postgr.es/m/CAA4eK1%2B1JyW5TiL%3DyV-3Uq1CrfnTyn0Xrk5uArt31Z%3D8rgPhXQ%40mail.gmail.com
Backpatch-through: 10
2022-09-01 19:24:19 +12:00
Bruce Momjian 3522131492 doc: in create statistics docs, mention analyze for parent info
Discussion: https://postgr.es/m/Yv1Bw8J+1pYfHiRl@momjian.us

Backpatch-through: 10
2022-08-31 23:11:46 -04:00
Bruce Momjian f4435ac720 doc: mention "bloom" as a possible index access method
Also remove USING erroneously added recently.

Reported-by: Jeff Janes

Discussion: https://postgr.es/m/CAMkU=1zhCpC7hottyMWM5Pimr9vRLprSwzLg+7PgajWhKZqRzw@mail.gmail.com

Backpatch-through: 10
2022-08-31 22:35:09 -04:00
Bruce Momjian d333a1a162 doc: use FILTER in aggregate example
Reported-by: michal.palenik@freemap.sk

Discussion: https://postgr.es/m/163499710897.684.7420075366995883688@wrigleys.postgresql.org

Backpatch-through: 10
2022-08-31 22:19:05 -04:00
Bruce Momjian 58d9107079 doc: split out the NATURAL/CROSS JOIN in SELECT syntax
This allows the syntax to be more accurate about what clauses are
supported.  Also switch an example query to use the ANSI join syntax.

Reported-by: Joel Jacobson

Discussion: https://postgr.es/m/67b71d3e-0c22-44df-a223-351f14418319@www.fastmail.com

Backpatch-through: 11
2022-08-31 21:46:23 -04:00
Tom Lane cc0e506a64 Port regress-python3-mangle.mk to Solaris "sed", redux.
Per experimentation and buildfarm failures, Solaris' "sed"
has got some kind of problem with regexes that use both '*'
and '[[:alpha:]]'.  We can work around that by replacing
'[[:alpha:]]' with '[a-zA-Z]', which is plenty good enough
for our purposes, especially since this is only needed in
long-stable branches.

I chose to flat-out remove the second pattern of this sort,
's/except \([a-zA-Z][a-zA-Z.]*\), *\([a-zA-Z][a-zA-Z]*\):/except \1 as \2:/g'
because we haven't needed it since 8.4.

Follow-on to c3556f6fa, which probably missed catching this
because the problematic pattern was already gone when that
patch was written.

Patch v10-v12 only, as the problem manifests only there.
We have a line of dead code in v13-v14, which isn't worth
changing, and the whole mess is gone as of v15.

Discussion: https://postgr.es/m/165561.1661984701@sss.pgh.pa.us
2022-08-31 21:33:45 -04:00
Bruce Momjian a3471ab93a doc: warn of SECURITY DEFINER schemas for non-sql_body functions
Non-sql_body functions are evaluated at runtime.

Reported-by: Erki Eessaar

Discussion: https://postgr.es/m/AM9PR01MB8268BF5E74E119828251FD34FE409@AM9PR01MB8268.eurprd01.prod.exchangelabs.com

Backpatch-through: 10
2022-08-31 21:10:37 -04:00
Bruce Momjian 16417ba58e doc: mention that SET TIME ZONE often needs to be quoted
Also mention that time zone abbreviations are not supported.

Reported-by: philippe.godfrin@nov.com

Discussion: https://postgr.es/m/163888728952.1269.5167822676466793158@wrigleys.postgresql.org

Backpatch-through: 10
2022-08-31 20:27:27 -04:00
Bruce Momjian e0d0c87a4c doc: document the maximum char/varchar length value
Reported-by: Japin Li

Discussion: https://postgr.es/m/MEYP282MB1669B13E98AE531617CB1386B6979@MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM

Backpatch-through: 10
2022-08-31 19:43:06 -04:00
Bruce Momjian 258c1af3a3 doc: show direction is optional in FETCH/MOVE's FROM/IN syntax
It used to show direction was required for FROM/IN.

Reported-by: Rob <rirans@comcast.net>

Discussion: https://postgr.es/m/20211015165248.isqjceyilelhnu3k@localhost

Author: Rob <rirans@comcast.net>

Backpatch-through: 10
2022-08-31 19:28:41 -04:00
Bruce Momjian cdb836cc2d doc: simplify WITH clause syntax in CREATE DATABASE
Reported-by: Rob <rirans@comcast.net>

Discussion: https://postgr.es/m/20211016171149.yaouvlw5kvux6dvk@localhost

Author: Rob <rirans@comcast.net>

Backpatch-through: 10
2022-08-31 17:08:44 -04:00
Tom Lane cb9232d166 Prevent long-term memory leakage in autovacuum launcher.
get_database_list() failed to restore the caller's memory context,
instead leaving current context set to TopMemoryContext which is
how CommitTransactionCommand() leaves it.  The callers both think
they are using short-lived contexts, for the express purpose of
not having to worry about cleaning up individual allocations.
The net effect therefore is that supposedly short-lived allocations
could accumulate indefinitely in the launcher's TopMemoryContext.

Although this has been broken for a long time, it seems we didn't
have any obvious memory leak here until v15's rearrangement of the
stats logic.  I (tgl) am not entirely convinced that there's no
other leak at all, though, and we're surely at risk of adding one
in future back-patched fixes.  So back-patch to all supported
branches, even though this may be only a latent bug in pre-v15.

Reid Thompson

Discussion: https://postgr.es/m/972a4e12b68b0f96db514777a150ceef7dcd2e0f.camel@crunchydata.com
2022-08-31 16:23:20 -04:00
Tom Lane f5aa855cd8 In the Snowball dictionary, don't try to stem excessively-long words.
If the input word exceeds 1000 bytes, don't pass it to the stemmer;
just return it as-is after case folding.  Such an input is surely
not a word in any human language, so whatever the stemmer might
do to it would be pretty dubious in the first place.  Adding this
restriction protects us against a known recursion-to-stack-overflow
problem in the Turkish stemmer, and it seems like good insurance
against any other safety or performance issues that may exist in
the Snowball stemmers.  (I note, for example, that they contain no
CHECK_FOR_INTERRUPTS calls, so we really don't want them running
for a long time.)  The threshold of 1000 bytes is arbitrary.

An alternative definition could have been to treat such words as
stopwords, but that seems like a bigger break from the old behavior.

Per report from Egor Chindyaskin and Alexander Lakhin.
Thanks to Olly Betts for the recommendation to fix it this way.

Discussion: https://postgr.es/m/1661334672.728714027@f473.i.mail.ru
2022-08-31 10:42:05 -04:00
Tom Lane 6fd58ca770 On NetBSD, force dynamic symbol resolution at postmaster start.
The default of lazy symbol resolution means that when the postmaster
first reaches the select() call in ServerLoop, it'll need to resolve
the link to that libc entry point.  NetBSD's dynamic loader takes
an internal lock while doing that, and if a signal interrupts the
operation then there is a risk of self-deadlock should the signal
handler do anything that requires that lock, as several of the
postmaster signal handlers do.  The window for this is pretty narrow,
and timing considerations make it unlikely that a signal would arrive
right then anyway.  But it's semi-repeatable on slow single-CPU
machines, and in principle the race could happen with any hardware.

The least messy solution to this is to force binding of dynamic
symbols at postmaster start, using the "-z now" linker option.
While we're at it, also use "-z relro" so as to provide a small
security gain.

It's not entirely clear whether any other platforms share this
issue, but for now we'll assume it's NetBSD-specific.  (We might
later try to use "-z now" on more platforms for performance
reasons, but that would not likely be something to back-patch.)

Report and patch by me; the idea to fix it this way is from
Andres Freund.

Discussion: https://postgr.es/m/3384826.1661802235@sss.pgh.pa.us
2022-08-30 17:29:17 -04:00
Robert Haas 002fba80eb Prevent WAL corruption after a standby promotion.
When a PostgreSQL instance performing archive recovery but not using
standby mode is promoted, and the last WAL segment that it attempted
to read ended in a partial record, the previous code would create
invalid WAL on the new timeline. The WAL from the previously timeline
would be copied to the new timeline up until the end of the last valid
record, but instead of beginning to write WAL at immediately
afterwards, the promoted server would write an overwrite contrecord at
the beginning of the next segment. The end of the previous segment
would be left as all-zeroes, resulting in failures if anything tried
to read WAL from that file.

The root of the issue is that ReadRecord() decides whether to set
abortedRecPtr and missingContrecPtr based on the value of StandbyMode,
but ReadRecord() switches to a new timeline based on the value of
ArchiveRecoveryRequested. We shouldn't try to write an overwrite
contrecord if we're switching to a new timeline, so change the test in
ReadRecod() to check ArchiveRecoveryRequested instead.

Code fix by Dilip Kumar. Comments by me incorporating suggested
language from Álvaro Herrera. Further review from Kyotaro Horiguchi
and Sami Imseih.

Discussion: http://postgr.es/m/CAFiTN-t7umki=PK8dT1tcPV=mOUe2vNhHML6b3T7W7qqvvajjg@mail.gmail.com
Discussion: http://postgr.es/m/FB0DEA0B-E14E-43A0-811F-C1AE93D00FF3%40amazon.com
2022-08-29 12:06:30 -04:00
Tom Lane 9a2c6b26e1 Doc: fix example of recursive query.
Compute total number of sub-parts correctly, per jason@banfelder.net

Simon Riggs

Discussion: https://postgr.es/m/166161184718.1235920.6304070286124217754@wrigleys.postgresql.org
2022-08-28 10:44:52 -04:00
Tom Lane d9ebc582fb Repair rare failure of MULTIEXPR_SUBLINK subplans in inherited updates.
Prior to v14, if we have a MULTIEXPR SubPlan (that is, use of the syntax
UPDATE ... SET (c1, ...) = (SELECT ...)) in an UPDATE with an inherited
or partitioned target table, inheritance_planner() will clone the
targetlist and therefore also the MULTIEXPR SubPlan and the Param nodes
referencing it for each child target table.  Up to now, we've allowed
all the clones to share the underlying subplan as well as the output
parameter IDs -- that is, the runtime ParamExecData slots.  That
technique is borrowed from the far older code that supports initplans,
and it works okay in that case because the cloned SubPlan nodes are
essentially identical.  So it doesn't matter which one of the clones
the shared ParamExecData.execPlan field might point to.

However, this fails to hold for MULTIEXPR SubPlans, because they can
have nonempty "args" lists (values to be passed into the subplan), and
those lists could get mutated to different states in the various clones.
In the submitted reproducer, as well as the test case added here, one
clone contains Vars with varno OUTER_VAR where another has INNER_VAR,
because the child tables are respectively on the outer or inner side of
the join.  Sharing the execPlan pointer can result in trying to evaluate
an args list that doesn't match the local execution state, with mayhem
ensuing.  The result often is to trigger consistency checks in the
executor, but I believe this could end in a crash or incorrect updates.

To fix, assign new Param IDs to each of the cloned SubPlans, so that
they don't share ParamExecData slots at runtime.  It still seems fine
for the clones to share the underlying subplan, and extra ParamExecData
slots are cheap enough that this fix shouldn't cost much.

This has been busted since we invented MULTIEXPR SubPlans in 9.5.
Probably the lack of previous reports is because query plans in which
the different clones of a MULTIEXPR mutate to effectively-different
states are pretty rare.  There's no issue in v14 and later, because
without inheritance_planner() there's never a reason to clone
MULTIEXPR SubPlans.

Per bug #17596 from Andre Lin.  Patch v10-v13 only.

Discussion: https://postgr.es/m/17596-c5357f61427a81dc@postgresql.org
2022-08-27 12:11:20 -04:00
Etsuro Fujita 1d40200a98 Fix typo in comment. 2022-08-26 16:55:07 +09:00
Tom Lane 310d734efb Defend against stack overrun in a few more places.
SplitToVariants() in the ispell code, lseg_inside_poly() in geo_ops.c,
and regex_selectivity_sub() in selectivity estimation could recurse
until stack overflow; fix by adding check_stack_depth() calls.
So could next() in the regex compiler, but that case is better fixed by
converting its tail recursion to a loop.  (We probably get better code
that way too, since next() can now be inlined into its sole caller.)

There remains a reachable stack overrun in the Turkish stemmer, but
we'll need some advice from the Snowball people about how to fix that.

Per report from Egor Chindyaskin and Alexander Lakhin.  These mistakes
are old, so back-patch to all supported branches.

Richard Guo and Tom Lane

Discussion: https://postgr.es/m/1661334672.728714027@f473.i.mail.ru
2022-08-24 13:01:40 -04:00
Tom Lane 04056e9268 Doc: document possible need to raise kernel's somaxconn limit.
On fast machines, it's possible for applications such as pgbench
to issue connection requests so quickly that the postmaster's
listen queue overflows in the kernel, resulting in unexpected
failures (with not-very-helpful error messages).  Most modern OSes
allow the queue size to be increased, so document how to do that.

Per report from Kevin McKibbin.

Discussion: https://postgr.es/m/CADc_NKg2d+oZY9mg4DdQdoUcGzN2kOYXBu-3--RW_hEe0tUV=g@mail.gmail.com
2022-08-23 09:56:07 -04:00
Tom Lane d0371f190a Doc: prefer sysctl to /proc/sys in docs and comments.
sysctl is more portable than Linux's /proc/sys file tree, and
often easier to use too.  That's why most of our docs refer to
sysctl when talking about how to adjust kernel parameters.
Bring the few stragglers into line.

Discussion: https://postgr.es/m/361175.1661187463@sss.pgh.pa.us
2022-08-23 09:42:28 -04:00
Amit Kapila 51e9469a41 Add CHECK_FOR_INTERRUPTS while decoding changes.
While decoding changes in a loop, if we skip all the changes there is no
CFI making the loop uninterruptible.

Reported-by: Whale Song and Andrey Borodin
Bug: 17580
Author: Masahiko Sawada
Reviwed-by: Amit Kapila
Backpatch-through: 10
Discussion: https://postgr.es/m/17580-849c1d5b6d7eb422@postgresql.org
Discussion: https://postgr.es/m/B319ECD6-9A28-4CDF-A8F4-3591E0BF2369@yandex-team.ru
2022-08-23 08:42:51 +05:30
Tom Lane 116f20f926 Fix subtly-incorrect matching of parent and child partitioned indexes.
When creating a partitioned index, DefineIndex tries to identify
any existing indexes on the partitions that match the partitioned
index, so that it can absorb those as child indexes instead of
building new ones.  Part of the matching is to compare IndexInfo
structs --- but that wasn't done quite right.  We're comparing
the IndexInfo built within DefineIndex itself to one made from
existing catalog contents by BuildIndexInfo.  Notably, while
BuildIndexInfo will run index expressions and predicates through
expression preprocessing, that has not happened to DefineIndex's
struct.  The result is failure to match and subsequent creation
of duplicate indexes.

The easiest and most bulletproof fix is to build a new IndexInfo
using BuildIndexInfo, thereby guaranteeing that the processing done
is identical.

While here, let's also extract the opfamily and collation data
from the new partitioned index, removing ad-hoc logic that
duplicated knowledge about how those are constructed.

Per report from Christophe Pettus.  Back-patch to v11 where
we invented partitioned indexes.

Richard Guo and Tom Lane

Discussion: https://postgr.es/m/8864BFAA-81FD-4BF9-8E06-7DEB8D4164ED@thebuild.com
2022-08-18 12:11:47 -04:00
Tatsuo Ishii 9d4c9c35ba doc: fix wrong tag used in create sequence manual.
In ref/create_sequence.sgml <literal> tag was used for nextval function name.
This should have been <function> tag.

Author: Noboru Saito
Discussion: https://postgr.es/m/CAAM3qnJTDFFfRf5JHJ4AYrNcqXgMmj0pbH0%2Bvm%3DYva%2BpJyGymA%40mail.gmail.com
Backpatch-through: 10
2022-08-16 09:29:20 +09:00
Tom Lane ee4a17e200 Add missing bad-PGconn guards in libpq entry points.
There's a convention that externally-visible libpq functions should
check for a NULL PGconn pointer, and fail gracefully instead of
crashing.  PQflush() and PQisnonblocking() didn't get that memo
though.  Also add a similar check to PQdefaultSSLKeyPassHook_OpenSSL;
while it's not clear that ordinary usage could reach that with a
null conn pointer, it's cheap enough to check, so let's be consistent.

Daniele Varrazzo and Tom Lane

Discussion: https://postgr.es/m/CA+mi_8Zm_mVVyW1iNFgyMd9Oh0Nv8-F+7Y3-BqwMgTMHuo_h2Q@mail.gmail.com
2022-08-15 15:40:07 -04:00
Michael Paquier 6e086bb1db Fix outdated --help message for postgres -f
This option switch supports a total of 8 values, as told by
set_plan_disabling_options() and the documentation, but this was not
reflected in the output generated by --help.

Author: Junwang Zhao
Discussion: https://postgr.es/m/CAEG8a3+pT3cWzyjzKs184L1XMNm8NDnoJLiSjAYSO7XqpRh_vA@mail.gmail.com
Backpatch-through: 10
2022-08-15 13:37:44 +09:00
Tom Lane 84f9691a19 Preserve memory context of VarStringSortSupport buffers.
When enlarging the work buffers of a VarStringSortSupport object,
varstrfastcmp_locale was careful to keep them in the ssup_cxt
memory context; but varstr_abbrev_convert just used palloc().
The latter creates a hazard that the buffers could be freed out
from under the VarStringSortSupport object, resulting in stomping
on whatever gets allocated in that memory later.

In practice, because we only use this code for ICU collations
(cf. 3df9c374e), the problem is confined to use of ICU collations.
I believe it may have been unreachable before the introduction
of incremental sort, too, as traditional sorting usually just
uses one context for the duration of the sort.

We could fix this by making the broken stanzas in varstr_abbrev_convert
match the non-broken ones in varstrfastcmp_locale.  However, it seems
like a better idea to dodge the issue altogether by replacing the
pfree-and-allocate-anew coding with repalloc, which automatically
preserves the chunk's memory context.  This fix does add a few cycles
because repalloc will copy the chunk's content, which the existing
coding assumes is useless.  However, we don't expect that these buffer
enlargement operations are performance-critical.  Besides that, it's
far from obvious that copying the buffer contents isn't required, since
these stanzas make no effort to mark the buffers invalid by resetting
last_returned, cache_blob, etc.  That seems to be safe upon examination,
but it's fragile and could easily get broken in future, which wouldn't
get revealed in testing with short-to-moderate-size strings.

Per bug #17584 from James Inform.  Whether or not the issue is
reachable in the older branches, this code has been broken on its
own terms from its introduction, so patch all the way back.

Discussion: https://postgr.es/m/17584-95c79b4a7d771f44@postgresql.org
2022-08-14 12:05:27 -04:00
Tom Lane b744e13b02 Catch stack overflow when recursing in transformFromClauseItem().
Most parts of the parser can expect that the stack overflow check
in transformExprRecurse() will trigger before things get desperate.
However, transformFromClauseItem() can recurse directly to self
without having analyzed any expressions, so it's possible to drive
it to a stack-overrun crash.  Add a check to prevent that.

Per bug #17583 from Egor Chindyaskin.  Back-patch to all supported
branches.

Richard Guo

Discussion: https://postgr.es/m/17583-33be55b9f981f75c@postgresql.org
2022-08-13 15:21:28 -04:00
Peter Eisentraut db9ec28d64 Add missing fields to _outConstraint()
As of 897795240c, check constraints can
be declared invalid.  But that patch didn't update _outConstraint() to
also show the relevant struct fields (which were only applicable to
foreign keys before that).  This currently only affects debugging
output, so no impact in practice.
2022-08-13 10:37:55 +02:00
Peter Eisentraut e5c2feac0e pg_upgrade: Fix some minor code issues
96ef3b8ff1 accidentally copied a not
applicable comment from the float8_pass_by_value code to the
data_checksums code.  Remove that.

87d3b35a1c changed pg_upgrade to
checking the checksum version rather than just the Boolean presence of
checksums, but didn't change the field type in its ControlData struct
from bool.  So this would not work correctly if there ever is a
checksum version larger than 1.
2022-08-13 00:16:17 +02:00
Bruce Momjian aca0ccdbb2 doc: add missing role attributes to user management section
Reported-by: Shinya Kato

Discussion: https://postgr.es/m/1ecdb1ff78e9b03dfce37e85eaca725a@oss.nttdata.com

Author: Shinya Kato

Backpatch-through: 10
2022-08-12 15:43:23 -04:00
Bruce Momjian 99c1f24f5b doc: add section about heap-only tuples (HOT)
Reported-by: Jonathan S. Katz

Discussion: https://postgr.es/m/c59ffbd5-96ac-a5a5-a401-14f627ca1405@postgresql.org

Backpatch-through: 11
2022-08-12 15:05:12 -04:00
Bruce Momjian 41fde30196 doc: warn about security issues around log files
Reported-by: Simon Riggs

Discussion: https://postgr.es/m/CANP8+jJESuuXYq9Djvf-+tx2vY2OFLmfEuu+UvwHNJ1RT7iJCQ@mail.gmail.com

Author: Simon Riggs

Backpatch-through: 10
2022-08-12 12:02:20 -04:00
Bruce Momjian 0663212126 doc: clarify configuration file for Windows builds
The use of file 'config.pl' was not clearly explained.

Reported-by: liambowen@gmail.com

Discussion: https://postgr.es/m/164246013804.31952.4958087335645367498@wrigleys.postgresql.org

Backpatch-through: 10
2022-08-12 11:35:22 -04:00
Bruce Momjian fd868582e2 doc: document the CREATE INDEX "USING" clause
Somehow this was in the syntax but had no description.

Reported-by: robertcorrington@gmail.com

Discussion: https://postgr.es/m/164228771825.31954.2719791849363756957@wrigleys.postgresql.org

Backpatch-through: 10
2022-08-12 11:26:03 -04:00