PostgreSQL 11.4 commit log

commit   : e5f26d79badfae8018ac70f2137158fe36246c2b    
  
author   : Tom Lane <[email protected]>    
date     : Mon, 17 Jun 2019 17:15:30 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Mon, 17 Jun 2019 17:15:30 -0400    

commit   : a4e4418c3f68986607d7b588389e026108c79d71    
  
author   : Tom Lane <[email protected]>    
date     : Mon, 17 Jun 2019 10:53:45 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Mon, 17 Jun 2019 10:53:45 -0400    

Security: CVE-2019-10164  

commit   : bf94911d437c1c2524feb0bdb07b7263e7399abd    
  
author   : Peter Eisentraut <[email protected]>    
date     : Mon, 17 Jun 2019 15:04:41 +0200    
  
committer: Peter Eisentraut <[email protected]>    
date     : Mon, 17 Jun 2019 15:04:41 +0200    

Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git  
Source-Git-Hash: 599a4bccd28710a88972e1a0ef6961c9bad816fc  

commit   : 27c464e42a9e3cb3779d1ea63b835a3e191682d6    
  
author   : Michael Paquier <[email protected]>    
date     : Mon, 17 Jun 2019 22:14:04 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Mon, 17 Jun 2019 22:14:04 +0900    

When a client connects to a rogue server sending specifically-crafted  
messages, this can suffice to execute arbitrary code as the operating  
system account used by the client.  
  
While on it, fix one error handling when decoding an incorrect salt  
included in the first message received from server.  
  
Author: Michael Paquier  
Reviewed-by: Jonathan Katz, Heikki Linnakangas  
Security: CVE-2019-10164  
Backpatch-through: 10  

commit   : 4c779ce324a15ffa0171160c52579130f25fcd3f    
  
author   : Michael Paquier <[email protected]>    
date     : Mon, 17 Jun 2019 21:48:25 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Mon, 17 Jun 2019 21:48:25 +0900    

Any authenticated user can overflow a stack-based buffer by changing the  
user's own password to a purpose-crafted value.  This often suffices to  
execute arbitrary code as the PostgreSQL operating system account.  
  
This fix is contributed by multiple folks, based on an initial analysis  
from Tom Lane.  This issue has been introduced by 68e61ee, so it was  
possible to make use of it at authentication time.  It became more  
easily to trigger after ccae190 which has made the SCRAM parsing more  
strict when changing a password, in the case where the client passes  
down a verifier already hashed using SCRAM.  Back-patch to v10 where  
SCRAM has been introduced.  
  
Reported-by: Alexander Lakhin  
Author: Jonathan Katz, Heikki Linnakangas, Michael Paquier  
Security: CVE-2019-10164  
Backpatch-through: 10  

commit   : 28dc2c25c579232dbba98a0ec62476b4091df96e    
  
author   : Alvaro Herrera <[email protected]>    
date     : Sun, 16 Jun 2019 22:24:21 -0400    
  
committer: Alvaro Herrera <[email protected]>    
date     : Sun, 16 Jun 2019 22:24:21 -0400    

This reverts commits 3da73d6839dc and de87a084c0a5.  
  
This code has some tricky corner cases that I'm not sure are correct and  
not properly tested anyway, so I'm reverting the whole thing for next  
week's releases (reintroducing the deadlock bug that we set to fix).  
I'll try again afterwards.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : f5ee6a7acc5db0d77f73aa1db531a684179b5478    
  
author   : Tom Lane <[email protected]>    
date     : Sun, 16 Jun 2019 14:47:34 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Sun, 16 Jun 2019 14:47:34 -0400    

Also improve wording of some items (thanks to Noah Misch for suggestions).  

commit   : 7f28fc8e929e9c63a489de4a359464d700025930    
  
author   : Andrew Gierth <[email protected]>    
date     : Sat, 15 Jun 2019 18:15:23 +0100    
  
committer: Andrew Gierth <[email protected]>    
date     : Sat, 15 Jun 2019 18:15:23 +0100    

tzdb 2019a made "UCT" a link to the "UTC" zone rather than a separate  
zone with its own abbreviation. Unfortunately, our code for choosing a  
timezone in initdb has an arbitrary preference for names earlier in  
the alphabet, and so it would choose the spelling "UCT" over "UTC"  
when the system is running on a UTC zone.  
  
Commit 23bd3cec6 was backpatched in order to address this issue, but  
that code helps only when /etc/localtime exists as a symlink, and does  
nothing to help on systems where /etc/localtime is a copy of a zone  
file (as is the standard setup on FreeBSD and probably some other  
platforms too) or when /etc/localtime is simply absent (giving UTC as  
the default).  
  
Accordingly, add a preference for the spelling "UTC", such that if  
multiple zone names have equally good content matches, we prefer that  
name before applying the existing arbitrary rules. Also add a slightly  
lower preference for "Etc/UTC"; lower because that preserves the  
previous behaviour of choosing the shorter name, but letting us still  
choose "Etc/UTC" over "Etc/UCT" when both exist but "UTC" does  
not (not common, but I've seen it happen).  
  
Backpatch all the way, because the tzdb change that sparked this issue  
is in those branches too.  

commit   : 0995cefa74510ee0e38d1bf095b2eef2c1ea37c4    
  
author   : Tom Lane <[email protected]>    
date     : Fri, 14 Jun 2019 16:56:49 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Fri, 14 Jun 2019 16:56:49 -0400    

As usual, the release notes for other branches will be made by cutting  
these down, but put them up for community review first.  

commit   : 1f8f144fe3a98928a026af9c2a45e57a962cc90d    
  
author   : Alvaro Herrera <[email protected]>    
date     : Fri, 14 Jun 2019 11:33:40 -0400    
  
committer: Alvaro Herrera <[email protected]>    
date     : Fri, 14 Jun 2019 11:33:40 -0400    

Introduced in de87a084c0a5.  

commit   : 995b4fe0b14fddb8cbe349809116e2bad260fd31    
  
author   : Tom Lane <[email protected]>    
date     : Fri, 14 Jun 2019 11:25:13 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Fri, 14 Jun 2019 11:25:13 -0400    

On many modern platforms, /etc/localtime is a symlink to a file within the  
IANA database.  Reading the symlink lets us find out the name of the system  
timezone directly, without going through the brute-force search embodied in  
scan_available_timezones().  This shortens the runtime of initdb by some  
tens of ms, which is helpful for the buildfarm, and it also allows us to  
reliably select the same zone name the system was actually configured for,  
rather than possibly choosing one of IANA's many zone aliases.  (For  
example, in a system configured for "Asia/Tokyo", the brute-force search  
would not choose that name but its alias "Japan", on the grounds of the  
latter string being shorter.  More surprisingly, "Navajo" is preferred  
to either "America/Denver" or "US/Mountain", as seen in an old complaint  
from Josh Berkus.)  
  
If /etc/localtime doesn't exist, or isn't a symlink, or we can't make  
sense of its contents, or the contents match a zone we know but that  
zone doesn't match the observed behavior of localtime(), fall back to  
the brute-force search.  
  
Also, tweak initdb so that it prints the zone name it selected.  
  
In passing, replace the last few references to the "Olson" database in  
code comments with "IANA", as that's been our preferred term since  
commit b2cbced9e.  
  
Back-patch of commit 23bd3cec6.  The original intention was to not  
back-patch, since this can result in cosmetic behavioral changes ---  
for example, on my own workstation initdb now chooses "America/New_York",  
where it used to prefer "US/Eastern" which is equivalent and shorter.  
However, our hand has been more or less forced by tzdb update 2019a,  
which made the "UCT" zone fully equivalent to "UTC".  Our old code  
now prefers "UCT" on the grounds of it being alphabetically first,  
and that's making nobody happy.  Choosing the alias indicated by  
/etc/localtime is a more defensible behavior.  (Users who don't like  
the results can always force the decision by setting the TZ environment  
variable before running initdb.)  
  
Patch by me, per a suggestion from Robert Haas; review by Michael Paquier  
  
Discussion: https://postgr.es/m/[email protected]  
Discussion: https://postgr.es/m/[email protected]  

commit   : 85600b7b5da42c5166eb1188c173beb3cc356178    
  
author   : Alvaro Herrera <[email protected]>    
date     : Thu, 13 Jun 2019 17:28:24 -0400    
  
committer: Alvaro Herrera <[email protected]>    
date     : Thu, 13 Jun 2019 17:28:24 -0400    

When two (or more) transactions are waiting for transaction T1 to release a  
tuple-level lock, and transaction T1 upgrades its lock to a higher level, a  
spurious deadlock can be reported among the waiting transactions when T1  
finishes.  The simplest example case seems to be:  
  
T1: select id from job where name = 'a' for key share;  
Y: select id from job where name = 'a' for update; -- starts waiting for X  
Z: select id from job where name = 'a' for key share;  
T1: update job set name = 'b' where id = 1;  
Z: update job set name = 'c' where id = 1; -- starts waiting for X  
T1: rollback;  
  
At this point, transaction Y is rolled back on account of a deadlock: Y  
holds the heavyweight tuple lock and is waiting for the Xmax to be released,  
while Z holds part of the multixact and tries to acquire the heavyweight  
lock (per protocol) and goes to sleep; once X releases its part of the  
multixact, Z is awakened only to be put back to sleep on the heavyweight  
lock that Y is holding while sleeping.  Kaboom.  
  
This can be avoided by having Z skip the heavyweight lock acquisition.  As  
far as I can see, the biggest downside is that if there are multiple Z  
transactions, the order in which they resume after X finishes is not  
guaranteed.  
  
Backpatch to 9.6.  The patch applies cleanly on 9.5, but the new tests don't  
work there (because isolationtester is not smart enough), so I'm not going  
to risk it.  
  
Author: Oleksii Kliukin  
Discussion: https://postgr.es/m/[email protected]  

commit   : 07accce500d81957d059761a1055702d147b29a7    
  
author   : Tom Lane <[email protected]>    
date     : Thu, 13 Jun 2019 10:53:17 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Thu, 13 Jun 2019 10:53:17 -0400    

Also MyReplicationSlot, in branches where it wasn't already.  
  
This was discussed in the thread that resulted in c572599c6, but  
for some reason nobody pulled the trigger.  Now that we have another  
request for the same thing, we should just do it.  
  
Craig Ringer  
  
Discussion: https://postgr.es/m/CAMsr+YFTsq-86MnsNng=mPvjjh5EAbzfMK0ptJPvzyvpFARuRg@mail.gmail.com  
Discussion: https://postgr.es/m/[email protected]  

commit   : 2144601821618ddd007b4ce6b7f081a8ac6f65c9    
  
author   : Etsuro Fujita <[email protected]>    
date     : Thu, 13 Jun 2019 17:59:11 +0900    
  
committer: Etsuro Fujita <[email protected]>    
date     : Thu, 13 Jun 2019 17:59:11 +0900    

Previously, in postgresPlanForeignModify, we planned an UPDATE operation  
on a foreign table so that we transmit only columns that were explicitly  
targets of the UPDATE, so as to avoid unnecessary data transmission, but  
if there were BEFORE ROW UPDATE triggers on the foreign table, those  
triggers might change values for non-target columns, in which case we  
would miss sending changed values for those columns.  Prevent optimizing  
away transmitting all columns if there are BEFORE ROW UPDATE triggers on  
the foreign table.  
  
This is an oversight in commit 7cbe57c34 which added triggers on foreign  
tables, so apply the patch all the way back to 9.4 where that came in.  
  
Author: Shohei Mochizuki  
Reviewed-by: Amit Langote  
Discussion: https://postgr.es/m/[email protected]  

commit   : afaa32daf293163cb9612bdb20a04a5fcb26309d    
  
author   : Tom Lane <[email protected]>    
date     : Wed, 12 Jun 2019 22:54:46 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Wed, 12 Jun 2019 22:54:46 -0400    

datatype.sgml failed to explain that boolin() accepts any unique  
prefix of the basic input strings.  Indeed it was actively misleading  
because it called out a few minimal prefixes without mentioning that  
there were more valid inputs.  
  
I also felt that it wasn't doing anybody any favors by conflating  
SQL key words, valid Boolean input, and string literals containing  
valid Boolean input.  Rewrite in hopes of reducing the confusion.  
  
Per bug #15836 from Yuming Wang, as diagnosed by David Johnston.  
Back-patch to supported branches.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : f95d8f81062a7afa00fa034022724734a1ff5e60    
  
author   : Tom Lane <[email protected]>    
date     : Wed, 12 Jun 2019 19:42:38 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Wed, 12 Jun 2019 19:42:38 -0400    

Given a query in which multiple JOIN nodes used the same alias  
(which'd necessarily be in different sub-SELECTs), ruleutils.c  
would assign the JOIN nodes distinct aliases for clarity ...  
but then it forgot to print the modified aliases when dumping  
the JOIN nodes themselves.  This results in a dump/reload hazard  
for views, because the emitted query is flat-out incorrect:  
Vars will be printed with table names that have no referent.  
  
This has been wrong for a long time, so back-patch to all supported  
branches.  
  
Philip Dubé  
  
Discussion: https://postgr.es/m/CY4PR2101MB080246F2955FF58A6ED1FEAC98140@CY4PR2101MB0802.namprd21.prod.outlook.com  

commit   : e23338cec4fb088235f27949c4f298b9738877d9    
  
author   : David Rowley <[email protected]>    
date     : Thu, 13 Jun 2019 10:35:27 +1200    
  
committer: David Rowley <[email protected]>    
date     : Thu, 13 Jun 2019 10:35:27 +1200    

Reported-by: Amit Langote  
Discussion: https://postgr.es/m/CA+HiwqGZFkKi0TkBGYpr2_5qrRAbHZoP47AP1BRLUOUkfQdy_A@mail.gmail.com  
Backpatch-through: 10  

commit   : 9346d396fd4a643653b5f3822dbfbd9968b32679    
  
author   : Tom Lane <[email protected]>    
date     : Wed, 12 Jun 2019 17:29:48 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Wed, 12 Jun 2019 17:29:48 -0400    

This is quite unsafe, even for the case of ereport(FATAL) where we won't  
return control to the interrupted code, and despite this code's use of  
a flag to restrict the areas where we'd try to do it.  It's possible  
for example that we interrupt malloc or free while that's holding a lock  
that's meant to protect against cross-thread interference.  Then, any  
attempt to do malloc or free within ereport() will result in a deadlock,  
preventing the walreceiver process from exiting in response to SIGTERM.  
We hypothesize that this explains some hard-to-reproduce failures seen  
in the buildfarm.  
  
Hence, get rid of the immediate-exit code in WalRcvShutdownHandler,  
as well as the logic associated with WalRcvImmediateInterruptOK.  
Instead, we need to take care that potentially-blocking operations  
in the walreceiver's data transmission logic (libpqwalreceiver.c)  
will respond reasonably promptly to the process's latch becoming  
set and then call ProcessWalRcvInterrupts.  Much of the needed code  
for that was already present in libpqwalreceiver.c.  I refactored  
things a bit so that all the uses of PQgetResult use latch-aware  
waiting, but didn't need to do much more.  
  
These changes should be enough to ensure that libpqwalreceiver.c  
will respond promptly to SIGTERM whenever it's waiting to receive  
data.  In principle, it could block for a long time while waiting  
to send data too, and this patch does nothing to guard against that.  
I think that that hazard is mostly theoretical though: such blocking  
should occur only if we fill the kernel's data transmission buffers,  
and we don't generally send enough data to make that happen without  
waiting for input.  If we find out that the hazard isn't just  
theoretical, we could fix it by using PQsetnonblocking, but that  
would require more ticklish changes than I care to make now.  
  
Back-patch of commit a1a789eb5.  This problem goes all the way back  
to the origins of walreceiver; but given the substantial reworking  
the module received during the v10 cycle, it seems unsafe to assume  
that our testing on HEAD validates this patch for pre-v10 branches.  
And we'd need to back-patch some prerequisite patches (at least  
597a87ccc and its followups, maybe other things), increasing the risk  
of problems.  Given the dearth of field reports matching this problem,  
it's not worth much risk.  Hence back-patch to v10 and v11 only.  
  
Patch by me; thanks to Thomas Munro for review.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 0b6edb9fb3d24c73b21917945e830e1c84135575    
  
author   : Tom Lane <[email protected]>    
date     : Wed, 12 Jun 2019 12:29:24 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Wed, 12 Jun 2019 12:29:24 -0400    

ATExecAlterColumnType failed to consider the possibility that an index  
that needs to be rebuilt might be a child of a constraint that needs to be  
rebuilt.  We missed this so far because usually a constraint index doesn't  
have a direct dependency on its table, just on the constraint object.  
But if there's a WHERE clause, then dependency analysis of the WHERE  
clause results in direct dependencies on the column(s) mentioned in WHERE.  
This led to trying to drop and rebuild both the constraint and its  
underlying index.  
  
In v11/HEAD, we successfully drop both the index and the constraint,  
and then try to rebuild both, and of course the second rebuild hits a  
duplicate-index-name problem.  Before v11, it fails with obscure messages  
about a missing relation OID, due to trying to drop the index twice.  
  
This is essentially the same kind of problem noted in commit  
20bef2c31: the possible dependency linkages are broader than what  
ATExecAlterColumnType was designed for.  It was probably OK when  
written, but it's certainly been broken since the introduction of  
partial exclusion constraints.  Fix by adding an explicit check  
for whether any of the indexes-to-be-rebuilt belong to any of the  
constraints-to-be-rebuilt, and ignoring any that do.  
  
In passing, fix a latent bug introduced by commit 8b08f7d48: in  
get_constraint_index() we must "continue" not "break" when rejecting  
a relation of a wrong relkind.  This is harmless today because we don't  
expect that code path to be taken anyway; but if there ever were any  
relations to be ignored, the existing coding would have an extremely  
undesirable dependency on the order of pg_depend entries.  
  
Also adjust a couple of obsolete comments.  
  
Per bug #15835 from Yaroslav Schekin.  Back-patch to all supported  
branches.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : fa5f3a4bcca7c222b4ab5a6aba27373aea49a2ec    
  
author   : Michael Paquier <[email protected]>    
date     : Wed, 12 Jun 2019 11:30:41 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Wed, 12 Jun 2019 11:30:41 +0900    

For a non-superuser, changing a comment on a domain constraint was  
leading to a cache lookup failure as the code tried to perform the  
ownership lookup on the constraint OID itself, thinking that it was a  
type, but this check needs to happen on the type the domain constraint  
relies on.  As the type a domain constraint relies on can be guessed  
directly based on the constraint OID, first fetch its type OID and  
perform the ownership on it.  
  
This is broken since 7eca575, which has split the handling of comments  
for table constraints and domain constraints, so back-patch down to  
9.5.  
  
Reported-by: Clemens Ladisch  
Author: Daniel Gustafsson, Michael Paquier  
Reviewed-by: Álvaro Herrera  
Discussion: https://postgr.es/m/[email protected]  
Backpatch-through: 9.5  

commit   : 936b5e589e041d04c9dd9ad66883d45caaf0665e    
  
author   : David Rowley <[email protected]>    
date     : Wed, 12 Jun 2019 08:09:11 +1200    
  
committer: David Rowley <[email protected]>    
date     : Wed, 12 Jun 2019 08:09:11 +1200    

A few questionable partitioning designs have been cropping up lately  
around the mailing lists.  Generally, these cases have been partitioning  
using too many partitions which have caused performance or OOM problems for  
the users.  
  
Since we have very little else to guide users into good design, here we  
add a new section to the partitioning documentation with some best  
practise guidelines for good design.  
  
Reviewed-by: Justin Pryzby, Amit Langote, Alvaro Herrera  
Discussion: https://postgr.es/m/CAKJS1f-2rx+E9mG3xrCVHupefMjAp1+tpczQa9SEOZWyU7fjEA@mail.gmail.com  
Backpatch-through: 10  

commit   : 1c9034579c026562ae6db5a3f2d3a7678653b9ff    
  
author   : Tom Lane <[email protected]>    
date     : Tue, 11 Jun 2019 13:33:08 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Tue, 11 Jun 2019 13:33:08 -0400    

json_to_record(), when an output column is declared as type json or jsonb,  
should emit the corresponding field of the input JSON object.  But it got  
this slightly wrong when the field is just a string literal: it failed to  
escape the contents of the string.  That typically resulted in syntax  
errors if the string contained any double quotes or backslashes.  
  
jsonb_to_record() handles such cases correctly, but I added corresponding  
test cases for it too, to prevent future backsliding.  
  
Improve the documentation, as it provided only a very hand-wavy  
description of the conversion rules used by these functions.  
  
Per bug report from Robert Vollmert.  Back-patch to v10 where the  
error was introduced (by commit cf35346e8).  
  
Note that PG 9.4 - 9.6 also get this case wrong, but differently so:  
they feed the de-escaped contents of the string literal to json[b]_in.  
That behavior is less obviously wrong, so possibly it's being depended on  
in the field, so I won't risk trying to make the older branches behave  
like the newer ones.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : c0155601763a153658a72a628bd66ebacdd2670a    
  
author   : Andres Freund <[email protected]>    
date     : Mon, 10 Jun 2019 23:20:48 -0700    
  
committer: Andres Freund <[email protected]>    
date     : Mon, 10 Jun 2019 23:20:48 -0700    

Vignesh found this bug in the check function for  
default_table_access_method's check hook, but that was just copied  
from older GUCs. Investigation by Michael and me then found the bug in  
further places.  
  
When not connected to a database (e.g. in a walsender connection), we  
cannot perform (most) GUC checks that need database access. Even when  
only shared tables are needed, unless they're  
nailed (c.f. RelationCacheInitializePhase2()), they cannot be accessed  
without pg_class etc. being present.  
  
Fix by extending the existing IsTransactionState() checks to also  
check for MyDatabaseOid.  
  
Reported-By: Vignesh C, Michael Paquier, Andres Freund  
Author: Vignesh C, Andres Freund  
Discussion: https://postgr.es/m/CALDaNm1KXK9gbZfY-p_peRFm_XrBh1OwQO1Kk6Gig0c0fVZ2uw%40mail.gmail.com  
Backpatch: 9.4-  

commit   : 6a781c4f5fecc5cde5444459f4cd187872487bda    
  
author   : Alvaro Herrera <[email protected]>    
date     : Mon, 10 Jun 2019 18:56:23 -0400    
  
committer: Alvaro Herrera <[email protected]>    
date     : Mon, 10 Jun 2019 18:56:23 -0400    

Using PARTITION OF can result in column ordering being changed from the  
database being dumped, if the partition uses a column layout different  
from the parent's.  It's not pg_dump's job to editorialize on table  
definitions, so this is not acceptable; back-patch all the way back to  
pg10, where partitioned tables where introduced.  
  
This change also ensures that partitions end up in the correct  
tablespace, if different from the parent's; this is an oversight in  
ca4103025dfe (in pg12 only).  Partitioned indexes (in pg11) don't have  
this problem, because they're already created as independent indexes and  
attached to their parents afterwards.  
  
This change also has the advantage that the partition is restorable from  
the dump (as a standalone table) even if its parent table isn't  
restored.  
  
The original commits (3b23552ad8bb in branch master) failed to cover  
subsidiary column elements correctly, such as NOT NULL constraint and  
CHECK constraints, as reported by Rushabh Lathia (initially as a failure  
to restore serial columns).  They were reverted.  This recapitulation  
commit fixes those problems.  
  
Add some pg_dump tests to verify these things more exhaustively,  
including constraints with legacy-inheritance tables, which were not  
tested originally.  In branches 10 and 11, add a local constraint to the  
pg_dump test partition that was added by commit 2d7eeb1b1492 to master.  
  
Author: Álvaro Herrera, David Rowley  
Reviewed-by: Álvaro Herrera  
Discussion: https://postgr.es/m/CAKJS1f_1c260nOt_vBJ067AZ3JXptXVRohDVMLEBmudX1YEx-A@mail.gmail.com  
Discussion: https://postgr.es/m/[email protected]  
Discussion: https://postgr.es/m/CAGPqQf0iQV=PPOv2Btog9J9AwOQp6HmuVd6SbGTR_v3Zp2XT1w@mail.gmail.com  

commit   : bc93a5ab407051c382fdabc190d1d0ffd92efb60    
  
author   : Alexander Korotkov <[email protected]>    
date     : Mon, 10 Jun 2019 20:14:19 +0300    
  
committer: Alexander Korotkov <[email protected]>    
date     : Mon, 10 Jun 2019 20:14:19 +0300    

Descriptions of pg_trgm GUC options have % replaced with %% like it was  
a printf-like format.  But that's not needed since they are just plain strings.  
This commit fixed that.  Backpatch to last supported version since this error  
present from the beginning.  
  
Reported-by: Masahiko Sawada  
Discussion: https://postgr.es/m/CAD21AoAgPKODUsu9gqUFiNqEOAqedStxJ-a0sapsJXWWAVp%3Dxg%40mail.gmail.com  
Backpatch-through: 9.4  

commit   : 19dc23a5ef7559cf22cdf586b9b4be7ad4497ba0    
  
author   : Alexander Korotkov <[email protected]>    
date     : Mon, 10 Jun 2019 19:38:13 +0300    
  
committer: Alexander Korotkov <[email protected]>    
date     : Mon, 10 Jun 2019 19:38:13 +0300    

be8a7a68 introduced pg_trgm.strict_word_similarity_threshold GUC, but missed  
docs for that.  This commit fixes that.  
  
Discussion: https://postgr.es/m/fc907f70-448e-fda3-3aa4-209a59597af0%402ndquadrant.com  
Author: Ian Barwick  
Reviewed-by: Masahiko Sawada, Michael Paquier  
Backpatch-through: 9.6  

commit   : 76bccb12dbb8a683bd6659ab815d42bfad9b437c    
  
author   : Alexander Korotkov <[email protected]>    
date     : Mon, 10 Jun 2019 19:28:47 +0300    
  
committer: Alexander Korotkov <[email protected]>    
date     : Mon, 10 Jun 2019 19:28:47 +0300    

5871b884 introduced pg_trgm.word_similarity_threshold GUC, but its documentation  
contains wrong indentation.  This commit fixes that.  Backpatch for easier  
backpatching of other documentation fixes.  
  
Discussion: https://postgr.es/m/4c735d30-ab59-fc0e-45d8-f90eb5ed3855%402ndquadrant.com  
Author: Ian Barwick  
Backpatch-through: 9.6  

commit   : 12a45a20aa25468c56311e71320bb586c2490836    
  
author   : Heikki Linnakangas <[email protected]>    
date     : Fri, 7 Jun 2019 12:43:55 +0300    
  
committer: Heikki Linnakangas <[email protected]>    
date     : Fri, 7 Jun 2019 12:43:55 +0300    

It's harmless to call PQfreemem() with a NULL argument, so the only  
consequence was that if allocating 'schema' failed, but allocating 'table'  
or 'field' succeeded, we would leak a bit of memory. That's highly  
unlikely to happen, so this is just academical, but let's get it right.  
  
Per bug #15838 from Timur Birsh. Backpatch back to 9.5, where the  
PQfreemem() calls were introduced.  
  
Discussion: https://www.postgresql.org/message-id/[email protected]  

commit   : 17aa054a79961556da8f6bbc158a7786345ac926    
  
author   : Amit Kapila <[email protected]>    
date     : Fri, 7 Jun 2019 05:29:11 +0530    
  
committer: Amit Kapila <[email protected]>    
date     : Fri, 7 Jun 2019 05:29:11 +0530    

When this code was initially introduced in commit d1b7c1ff, the structure  
used was SharedPlanStateInstrumentation, but later when it got changed to  
Instrumentation structure in commit b287df70, we forgot to update the  
comment.  
  
Reported-by: Wu Fei  
Author: Wu Fei  
Reviewed-by: Amit Kapila  
Backpatch-through: 9.6  
Discussion: https://postgr.es/m/52E6E0843B9D774C8C73D6CF64402F0562215EB2@G08CNEXMBPEKD02.g08.fujitsu.local  

commit   : a15e8ce7b647ccc4580bf00374c33e5ab793f3e3    
  
author   : David Rowley <[email protected]>    
date     : Thu, 6 Jun 2019 12:37:04 +1200    
  
committer: David Rowley <[email protected]>    
date     : Thu, 6 Jun 2019 12:37:04 +1200    

Document that CREATE INDEX CONCURRENTLY is not currently supported for  
indexes on partitioned tables.  
  
Discussion: https://postgr.es/m/CAKJS1f_CErd2z9L21Q8OGLD4TgH7yw1z9MAtHTSO13sXVG-yow@mail.gmail.com  
Backpatch-through: 11  

commit   : a99b653ac1e6689d13d77622dd2c31309184f28c    
  
author   : Alvaro Herrera <[email protected]>    
date     : Tue, 4 Jun 2019 16:43:45 -0400    
  
committer: Alvaro Herrera <[email protected]>    
date     : Tue, 4 Jun 2019 16:43:45 -0400    

Continuous operation cannot be achieved without applying this technique,  
so it needs to be properly described.  
  
Author: Álvaro Herrera  
Reported-by: Tom Lane  
Discussion: https://postgr.es/m/[email protected]  

commit   : 57e85fa2cb7e7a99306be4b62c6a547532b7e849    
  
author   : Tom Lane <[email protected]>    
date     : Mon, 3 Jun 2019 18:06:04 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Mon, 3 Jun 2019 18:06:04 -0400    

A parallel worker process should not be making any decisions of its  
own about whether to auto-explain.  If the parent session process  
passed down flags asking for instrumentation data, do that, otherwise  
not.  Trying to enable instrumentation anyway leads to bugs like the  
"could not find key N in shm TOC" failure reported in bug #15821  
from Christian Hofstaedtler.  
  
We can implement this cheaply by piggybacking on the existing logic  
for not doing anything when we've chosen not to sample a statement.  
  
While at it, clean up some tin-eared coding related to the sampling  
feature, including an off-by-one error that meant that asking for 1.0  
sampling rate didn't actually result in sampling every statement.  
  
Although the specific case reported here only manifested in >= v11,  
I believe that related misbehaviors can be demonstrated in any version  
that has parallel query; and the off-by-one error is certainly there  
back to 9.6 where that feature was added.  So back-patch to 9.6.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 601084eb1aa8f1ae5303d9cf130d5b8cc385b517    
  
author   : Tom Lane <[email protected]>    
date     : Mon, 3 Jun 2019 16:59:16 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Mon, 3 Jun 2019 16:59:16 -0400    

It's not really supported to call systable_getnext() in a different  
memory context than systable_beginscan() was called in, and it's  
*definitely* not safe to do so and then reset that context between  
calls.  I'm not very clear on how this code survived  
CLOBBER_CACHE_ALWAYS testing ... but Alexander Lakhin found a case  
that would crash it pretty reliably.  
  
Per bug #15828.  Fix, and backpatch to v11 where this code came in.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 3c461d510dc5af7a7c4d4947ad7c2ef703e3646c    
  
author   : Michael Paquier <[email protected]>    
date     : Sat, 1 Jun 2019 15:33:58 -0400    
  
committer: Michael Paquier <[email protected]>    
date     : Sat, 1 Jun 2019 15:33:58 -0400    

Support of CHECK OPTION for updatable views has been added in 9.4, but  
the documentation of information_schema never got the call even if the  
information displayed is correct.  
  
Author: Gilles Darold  
Discussion: https://postgr.es/m/[email protected]  
Backpatch-through: 9.4  

commit   : 312017fcc46b56c7c2230dbe0908ba78b384735e    
  
author   : Tom Lane <[email protected]>    
date     : Fri, 31 May 2019 12:34:54 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Fri, 31 May 2019 12:34:54 -0400    

Rename some exposed parameters so that they don't conflict with  
C++ reserved words.  
  
Back-patch to all supported versions.  
  
George Tarasov  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 9c9a74cd3257324257ec016e800ce0a6d5af88c7    
  
author   : Tomas Vondra <[email protected]>    
date     : Thu, 30 May 2019 16:16:12 +0200    
  
committer: Tomas Vondra <[email protected]>    
date     : Thu, 30 May 2019 16:16:12 +0200    

Most errors reported in extended statistics are internal issues, and so  
should use elog(). The MCV list code was already following this rule, but  
the functional dependencies and ndistinct coefficients were using a mix  
of elog() and ereport(). Fix this by changing most places to elog(), with  
the exception of input functions.  
  
This is a mostly cosmetic change, it makes the life a little bit easier  
for translators, as elog() messages are not translated. So backpatch to  
PostgreSQL 10, where extended statistics were introduced.  
  
Author: Tomas Vondra  
Backpatch-through: 10 where extended statistics were added  
Discussion: https://postgr.es/m/[email protected]  

commit   : 88a0e3daf862def3503a69f89bc9eeecb7d73736    
  
author   : Noah Misch <[email protected]>    
date     : Tue, 28 May 2019 12:59:00 -0700    
  
committer: Noah Misch <[email protected]>    
date     : Tue, 28 May 2019 12:59:00 -0700    

When this suite runs installcheck, redirect file creations from  
src/test/regress to src/bin/pg_upgrade/tmp_check/regress.  This closes a  
race condition in "make -j check-world".  If the pg_upgrade suite wrote  
to a given src/test/regress/results file in parallel with the regular  
src/test/regress invocation writing it, a test failed spuriously.  Even  
without parallelism, in "make -k check-world", the suite finishing  
second overwrote the other's regression.diffs.  This revealed test  
"largeobject" assuming @abs_builddir@ is getcwd(), so fix that, too.  
  
Buildfarm client REL_10, released fifty-four days ago, supports saving  
regression.diffs from its new location.  When an older client reports a  
pg_upgradeCheck failure, it will no longer include regression.diffs.  
Back-patch to 9.5, where pg_upgrade moved to src/bin.  
  
Reviewed (in earlier versions) by Andrew Dunstan.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 20103a26094beeadb2019f5b86a57f6eee684d8e    
  
author   : Noah Misch <[email protected]>    
date     : Tue, 28 May 2019 12:58:30 -0700    
  
committer: Noah Misch <[email protected]>    
date     : Tue, 28 May 2019 12:58:30 -0700    

This allows "vcregress upgradecheck" to pass twice in immediate  
succession, and it's more like how $(prove_check) works.  Back-patch to  
9.5, where pg_upgrade moved to src/bin.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 329575db94cda78d467c52f71967acf26fcc5ce2    
  
author   : Tom Lane <[email protected]>    
date     : Fri, 24 May 2019 11:16:06 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Fri, 24 May 2019 11:16:06 -0400    

Per bug #15819 from Koizumi Satoru.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 5d91a9e8ac9cc6dc9d3695fcaa41132f2c4f0a89    
  
author   : Andres Freund <[email protected]>    
date     : Thu, 23 May 2019 14:46:57 -0700    
  
committer: Andres Freund <[email protected]>    
date     : Thu, 23 May 2019 14:46:57 -0700    

On master (after 700538) the old version's installed psql was used -  
even when the old version might not actually be installed / might be  
installed into a temporary directory. As commonly the case when just  
executing make check for pg_upgrade, as $oldbindir is just the current  
version's $bindir.  
  
In the back branches, with --install specified, psql from the new  
version's temporary installation was used, without --install (e.g for  
NO_TEMP_INSTALL, cf 47b3c26642), the new version's installed psql was  
used (which might or might not exist).  
  
Author: Andres Freund  
Discussion: https://postgr.es/m/[email protected]  

commit   : f7da492dca2a929045414aaf17f2e8cbf778df3d    
  
author   : Andrew Gierth <[email protected]>    
date     : Thu, 23 May 2019 15:26:01 +0100    
  
committer: Andrew Gierth <[email protected]>    
date     : Thu, 23 May 2019 15:26:01 +0100    

When there were duplicate columns in the hash key list, the array  
sizes could be miscomputed, resulting in access off the end of the  
array. Adjust the computation to ensure the array is always large  
enough.  
  
(I considered whether the duplicates could be removed in planning, but  
I can't rule out the possibility that duplicate columns might have  
different hash functions assigned. Simpler to just make sure it works  
at execution time regardless.)  
  
Bug apparently introduced in fc4b3dea2 as part of narrowing down the  
tuples stored in the hashtable. Reported by Colm McHugh of Salesforce,  
though I didn't use their patch. Backpatch back to version 10 where  
the bug was introduced.  
  
Discussion: https://postgr.es/m/CAFeeJoKKu0u+A_A9R9316djW-YW3-+Gtgvy3ju655qRHR3jtdA@mail.gmail.com  

commit   : a7b2fca15b2552e004c9c1af2bbf07d0d8ef7a8b    
  
author   : Michael Paquier <[email protected]>    
date     : Thu, 23 May 2019 10:48:24 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Thu, 23 May 2019 10:48:24 +0900    

This uses a method similar to 68a7c24f and now b8c6014 (applied for  
database creation), which guarantees that GRANT commands using the WITH  
GRANT OPTION are dumped in a way so as cascading dependencies are  
respected.  Note that tablespaces do not have support for initial  
privileges via pg_init_privs, so the same method needs to be applied  
again.  It would be nice to merge all the logic generating ACL queries  
in dumps under the same banner, but this requires extending the support  
of pg_init_privs to objects that cannot use it yet, so this is left as  
future work.  
  
Discussion: https://postgr.es/m/[email protected]  
Author: Michael Paquier  
Reviewed-by: Nathan Bossart  
Backpatch-through: 9.6  

commit   : 8357a413f439887ef243f9efd2417b1a7409e694    
  
author   : Michael Paquier <[email protected]>    
date     : Wed, 22 May 2019 14:48:14 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Wed, 22 May 2019 14:48:14 +0900    

This uses a method similar to 68a7c24f, which guarantees that GRANT  
commands using the WITH GRANT OPTION are dumped in a way so as cascading  
dependencies are respected.  As databases do not have support for  
initial privileges via pg_init_privs, we need to repeat again the same  
ACL reordering method.  
  
ACL for databases have been moved from pg_dumpall to pg_dump in v11, so  
this impacts pg_dump for v11 and above, and pg_dumpall for v9.6 and  
v10.  
  
Discussion: https://postgr.es/m/[email protected]  
Author: Nathan Bossart  
Reviewed-by: Haribabu Kommi  
Backpatch-through: 9.6  

commit   : 9fea0b0e287e39c96f1486b0af23102ac5b752a5    
  
author   : Andres Freund <[email protected]>    
date     : Sun, 19 May 2019 18:01:06 -0700    
  
committer: Andres Freund <[email protected]>    
date     : Sun, 19 May 2019 18:01:06 -0700    

For partial aggregation combine steps,  
AggStatePerTrans->numTransInputs was set to the transition function's  
number of inputs, rather than the combine function's number of  
inputs (always 1).  
  
That lead to partial aggregates with strict combine functions to  
wrongly check for NOT NULL input as required by strictness. When the  
aggregate wasn't exactly passed one argument, the strictness check was  
either omitted (in the 0 args case) or too many arguments were  
checked. In the latter case we'd read beyond the end of  
FunctionCallInfoData->args (only in master).  
  
AggStatePerTrans->numTransInputs actually has been wrong since since  
9.6, where partial aggregates were added. But it turns out to not be  
an active problem in 9.6 and 10, because numTransInputs wasn't used at  
all for combine functions: Before c253b722f6 there simply was no NULL  
check for the input to strict trans functions, and after that the  
check was simply hardcoded for the right offset in fcinfo, as it's  
done by code specific to combine functions.  
  
In bf6c614a2f2 (11) the strictness check was generalized, with common  
code doing the strictness checks for both plain and combine transition  
functions, based on numTransInputs. For combine functions this lead to  
not emitting an expression step to check for strict input in the 0  
arguments case, and in the > 1 arguments case, we'd check too many  
arguments.Due to the fact that the relevant fcinfo->isnull[2..] was  
always zero-initialized (more or less by accident, by being part of  
the AggStatePerTrans struct, which is palloc0'ed), there was no  
observable damage in the latter case before a9c35cf85ca1f, we just  
checked too many array elements.  
  
Due to the changes in a9c35cf85ca1f, > 1 argument bug became visible,  
because these days fcinfo is a) dynamically allocated without being  
zeroed b) exactly the length required for the number of specified  
arguments (hardcoded to 2 in this case).  
  
This commit only contains a fairly minimal fix, setting numTransInputs  
to a hardcoded 1 when building a pertrans for a combine function. It  
seems likely that we'll want to clean this up further (e.g. the  
arguments build_pertrans_for_aggref() aren't particularly meaningful  
for combine functions). But the wrap date for 12 beta1 is coming up  
fast, so it seems good to have a minimal fix in place.  
  
Backpatch to 11. While AggStatePerTrans->numTransInputs was set  
wrongly before that, the value was not used for combine functions.  
  
Reported-By: Rajkumar Raghuwanshi  
Diagnosed-By: Kyotaro Horiguchi, Jeevan Chalke, Andres Freund, David Rowley  
Author: David Rowley, Kyotaro Horiguchi, Andres Freund  
Discussion: https://postgr.es/m/CAKcux6=uZEyWyLw0N7HtR9OBc-sWEFeByEZC7t-KDf15FKxVew@mail.gmail.com  

commit   : 0950d25acec66ad02d2fc2d6d75a36ec334ed6f8    
  
author   : Michael Paquier <[email protected]>    
date     : Mon, 20 May 2019 09:48:27 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Mon, 20 May 2019 09:48:27 +0900    

Discussion: https://postgr.es/m/[email protected]  
Author: Liudmila Mantrova  
Reviewed-by: Jonathan Katz, Tom Lane, Michael Paquier  
Backpatch-through: 9.4  

commit   : 9518978e223b758f0efbc28422c5bf164d521f28    
  
author   : Noah Misch <[email protected]>    
date     : Sun, 19 May 2019 15:24:42 -0700    
  
committer: Noah Misch <[email protected]>    
date     : Sun, 19 May 2019 15:24:42 -0700    

This reverts commit bd1592e8570282b1650af6b8eede0016496daecd.  It had  
multiple defects.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : d08d880ab41afff57280e69b89144076ae068999    
  
author   : Noah Misch <[email protected]>    
date     : Sun, 19 May 2019 14:36:44 -0700    
  
committer: Noah Misch <[email protected]>    
date     : Sun, 19 May 2019 14:36:44 -0700    

When this suite runs installcheck, redirect file creations from  
src/test/regress to src/bin/pg_upgrade/tmp_check/regress.  This closes a  
race condition in "make -j check-world".  If the pg_upgrade suite wrote  
to a given src/test/regress/results file in parallel with the regular  
src/test/regress invocation writing it, a test failed spuriously.  Even  
without parallelism, in "make -k check-world", the suite finishing  
second overwrote the other's regression.diffs.  This revealed test  
"largeobject" assuming @abs_builddir@ is getcwd(), so fix that, too.  
  
Buildfarm client REL_10, released forty-five days ago, supports saving  
regression.diffs from its new location.  When an older client reports a  
pg_upgradeCheck failure, it will no longer include regression.diffs.  
Back-patch to 9.5, where pg_upgrade moved to src/bin.  
  
Reviewed by Andrew Dunstan.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 592d5d75be9720e575e76ba35c3ff04659ec0603    
  
author   : Tom Lane <[email protected]>    
date     : Fri, 17 May 2019 19:44:19 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Fri, 17 May 2019 19:44:19 -0400    

Previously, gen_partprune_steps() always built executor pruning steps  
using all suitable clauses, including those containing PARAM_EXEC  
Params.  This meant that the pruning steps were only completely safe  
for executor run-time (scan start) pruning.  To prune at executor  
startup, we had to ignore the steps involving exec Params.  But this  
doesn't really work in general, since there may be logic changes  
needed as well --- for example, pruning according to the last operator's  
btree strategy is the wrong thing if we're not applying that operator.  
The rules embodied in gen_partprune_steps() and its minions are  
sufficiently complicated that tracking their incremental effects in  
other logic seems quite impractical.  
  
Short of a complete redesign, the only safe fix seems to be to run  
gen_partprune_steps() twice, once to create executor startup pruning  
steps and then again for run-time pruning steps.  We can save a few  
cycles however by noting during the first scan whether we rejected  
any clauses because they involved exec Params --- if not, we don't  
need to do the second scan.  
  
In support of this, refactor the internal APIs in partprune.c to make  
more use of passing information in the GeneratePruningStepsContext  
struct, rather than as separate arguments.  
  
This is, I hope, the last piece of our response to a bug report from  
Alan Jackson.  Back-patch to v11 where this code came in.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 51948c4e1fdef88ba9b953bd7b58d19a348732be    
  
author   : Tom Lane <[email protected]>    
date     : Thu, 16 May 2019 16:25:43 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Thu, 16 May 2019 16:25:43 -0400    

gen_prune_steps_from_opexps's notion of how to do this was overly  
complicated and underly correct.  
  
Per discussion of a report from Alan Jackson (though this fixes only one  
aspect of that problem).  Back-patch to v11 where this code came in.  
  
Amit Langote  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 10c5cc4b4f88d249751e27034a8dd59ea903a698    
  
author   : Tom Lane <[email protected]>    
date     : Thu, 16 May 2019 11:58:22 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Thu, 16 May 2019 11:58:22 -0400    

Cross-type comparison operators in a btree or hash opclass might be  
only stable not immutable (this is true of timestamp vs. timestamptz  
for example).  partprune.c ignored this possibility and would perform  
plan-time pruning with them anyway, possibly leading to wrong answers  
if the environment changed between planning and execution.  
  
To fix, teach gen_partprune_steps() to do things differently when  
creating plan-time pruning steps vs. run-time pruning steps.  
analyze_partkey_exprs() also needs an extra check, which is rather  
annoying but now is not the time to restructure things enough to  
avoid that.  
  
While at it, simplify the logic for the plan-time case a little  
by insisting that the comparison value be a Const and nothing else.  
This relies on the assumption that eval_const_expressions will have  
reduced any immutable expression to a Const; which is not quite  
100% true, but certainly any case that comes up often enough to be  
interesting should have simplification logic there.  
  
Also improve a bunch of inadequate/obsolete/wrong comments.  
  
Per discussion of a report from Alan Jackson (though this fixes only one  
aspect of that problem).  Back-patch to v11 where this code came in.  
  
David Rowley, with some further hacking by me  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 05cf41973157577aac9706dcc7998054949b0ed4    
  
author   : Andres Freund <[email protected]>    
date     : Tue, 14 May 2019 11:45:40 -0700    
  
committer: Andres Freund <[email protected]>    
date     : Tue, 14 May 2019 11:45:40 -0700    

This path previously was not reliably covered. There was some  
heuristic coverage via insert-conflict-toast.spec, but that test is  
not deterministic, and only tested for a somewhat specific bug.  
  
Backpatch, as this is a complicated and otherwise untested code  
path. Unfortunately 9.5 cannot handle two waiting sessions, and thus  
cannot execute this test.  
  
Triggered by a conversion with Melanie Plageman.  
  
Author: Andres Freund  
Discussion: https://postgr.es/m/CAAKRu_a7hbyrk=wveHYhr4LbcRnRCG=yPUVoQYB9YO1CdUBE9Q@mail.gmail.com  
Backpatch: 9.5-  

commit   : 3293330f79af9d66e9df251266c882794edfec4e    
  
author   : Heikki Linnakangas <[email protected]>    
date     : Tue, 14 May 2019 13:06:33 +0300    
  
committer: Heikki Linnakangas <[email protected]>    
date     : Tue, 14 May 2019 13:06:33 +0300    

The conditions listed in this comment have changed several times, and at  
some point the thing that the "if so" referred to was negated.  
  
The text was OK up to 9.6. It was differently wrong in v10, v11 and  
master, so fix in all those versions.  

commit   : 6bbc2f9b66104de67f29881c54e75fd6f5d2f694    
  
author   : Peter Geoghegan <[email protected]>    
date     : Mon, 13 May 2019 15:39:05 -0700    
  
committer: Peter Geoghegan <[email protected]>    
date     : Mon, 13 May 2019 15:39:05 -0700    

An upcoming HEAD-only patch will standardize the terminology around  
ItemIdData variables/line pointers, ending the practice of referring to  
them as "item pointers".  Make the "Database Page Layout" docs  
consistent with the new policy.  The term "item identifier" is already  
used in the same section, so stick with that.  
  
Discussion: https://postgr.es/m/CAH2-Wz=c=MZQjUzde3o9+2PLAPuHTpVZPPdYxN=E4ndQ2--8ew@mail.gmail.com  
Backpatch: All supported branches.  

commit   : b6abc2241ac4549623d6894d7855765df6345ad5    
  
author   : Tom Lane <[email protected]>    
date     : Mon, 13 May 2019 17:23:00 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Mon, 13 May 2019 17:23:00 -0400    

Only hand-assigned type OIDs should be presumed to match across different  
PG servers; those assigned during genbki.pl or during initdb are likely  
to change due to addition or removal of unrelated objects.  
  
This means that the cutoff should be FirstGenbkiObjectId (in HEAD)  
or FirstBootstrapObjectId (before that), not FirstNormalObjectId.  
Compare postgres_fdw's is_builtin() test.  
  
It's likely that this error has no observable consequence in a  
normally-functioning system, since ATM the only affected type OIDs are  
system catalog rowtypes and information_schema types, which would not  
typically be interesting for logical replication.  But you could  
probably break it if you tried hard, so back-patch.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : bf78f50bae0b3b5ffcbf3e3c5b03fd138be15f9a    
  
author   : Peter Geoghegan <[email protected]>    
date     : Mon, 13 May 2019 10:27:57 -0700    
  
committer: Peter Geoghegan <[email protected]>    
date     : Mon, 13 May 2019 10:27:57 -0700    

Commit 8fa30f906be reduced the elevel of a number of "can't happen"  
_bt_split() errors from PANIC to ERROR.  At the same time, the new right  
page buffer for the split could continue to be acquired well before the  
critical section.  This was possible because it was relatively  
straightforward to make sure that _bt_split() could not throw an error,  
with a few specific exceptions.  The exceptional cases were safe because  
they involved specific, well understood errors, making it possible to  
consistently zero the right page before actually raising an error using  
elog().  There was no danger of leaving around a junk page, provided  
_bt_split() stuck to this coding rule.  
  
Commit 8224de4f, which introduced INCLUDE indexes, added code to make  
_bt_split() truncate away non-key attributes.  This happened at a point  
that broke the rule around zeroing the right page in _bt_split().  If  
truncation failed (perhaps due to palloc() failure), that would result  
in an errant right page buffer with junk contents.  This could confuse  
VACUUM when it attempted to delete the page, and should be avoided on  
general principle.  
  
To fix, reorganize _bt_split() so that truncation occurs before the new  
right page buffer is even acquired.  A junk page/buffer will not be left  
behind if _bt_nonkey_truncate()/_bt_truncate() raise an error.  
  
Discussion: https://postgr.es/m/CAH2-WzkcWT_-NH7EeL=Az4efg0KCV+wArygW8zKB=+HoP=VWMw@mail.gmail.com  
Backpatch: 11-, where INCLUDE indexes were introduced.  

commit   : 6b0e9411ff0f0116d6f9118a870a682a17eea110    
  
author   : Tom Lane <[email protected]>    
date     : Mon, 13 May 2019 10:53:19 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Mon, 13 May 2019 10:53:19 -0400    

pgtls_read_pending is declared to return bool, but what the underlying  
SSL_pending function returns is a count of available bytes.  
  
This is actually somewhat harmless if we're using C99 bools, but in  
the back branches it's a live bug: if the available-bytes count happened  
to be a multiple of 256, it would get converted to a zero char value.  
On machines where char is signed, counts of 128 and up could misbehave  
as well.  The net effect is that when using SSL, libpq might block  
waiting for data even though some has already been received.  
  
Broken by careless refactoring in commit 4e86f1b16, so back-patch  
to 9.5 where that came in.  
  
Per bug #15802 from David Binderman.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 6ba0ff47cd9a7e86298dca3ead112eb27ae21265    
  
author   : Etsuro Fujita <[email protected]>    
date     : Mon, 13 May 2019 17:30:37 +0900    
  
committer: Etsuro Fujita <[email protected]>    
date     : Mon, 13 May 2019 17:30:37 +0900    

commit   : 72ce7acaf3e60da712f0de1916704a4aec06600d    
  
author   : Tom Lane <[email protected]>    
date     : Sun, 12 May 2019 18:53:12 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Sun, 12 May 2019 18:53:12 -0400    

A bounded quantifier with m = n = 1 might be thought a no-op.  But  
according to our documentation (which traces back to Henry Spencer's  
original man page) it still imposes greediness, or non-greediness in the  
case of the non-greedy variant "{1,1}?", on whatever it's attached to.  
  
This turns out not to work though, because parseqatom() optimizes away  
the m = n = 1 case without regard for whether it's supposed to change  
the greediness of the argument RE.  
  
We can fix this by just not applying the optimization when the greediness  
needs to change; the subsequent general cases handle it fine.  
  
The three cases in which we can still apply the optimization are  
(a) no quantifier, or quantifier does not impose a preference;  
(b) atom has no greediness property, implying it cannot match a  
variable amount of text anyway; or  
(c) quantifier's greediness is same as atom's.  
Note that in most cases where one of these applies, we'd have exited  
earlier in the "not a messy case" fast path.  I think it's now only  
possible to get to the optimization when the atom involves capturing  
parentheses or a non-top-level backref.  
  
Back-patch to all supported branches.  I'd ordinarily be hesitant to  
put a subtle behavioral change into back branches, but in this case  
it's very hard to see a reason why somebody would write "{1,1}?" unless  
they're trying to get the documented change-of-greediness behavior.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 4ec14e5aa1f79d01a2558b694ccbe7756c4d186e    
  
author   : Noah Misch <[email protected]>    
date     : Sun, 12 May 2019 10:33:05 -0700    
  
committer: Noah Misch <[email protected]>    
date     : Sun, 12 May 2019 10:33:05 -0700    

The function had been interpreting SQL_ASCII messages as UTF8, throwing  
an error when they were invalid UTF8.  The new behavior is consistent  
with pg_do_encoding_conversion().  This affects LOG_DESTINATION_STDERR  
and LOG_DESTINATION_EVENTLOG, which will send untranslated bytes to  
write() and ReportEventA().  On buildfarm member bowerbird, enabling  
log_connections caused an error whenever the role name was not valid  
UTF8.  Back-patch to 9.4 (all supported versions).  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : eb97242c2f78869376277567dcb8102283368489    
  
author   : Tom Lane <[email protected]>    
date     : Sat, 11 May 2019 21:27:13 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Sat, 11 May 2019 21:27:13 -0400    

We long ago decided to design the shared PgBackendStatus data structure to  
minimize the cost of writing status updates, which means that writers just  
have to increment the st_changecount field twice.  That isn't hooked into  
any sort of resource management mechanism, which means that if something  
were to throw error between the two increments, the st_changecount field  
would be left odd indefinitely.  That would cause readers to lock up.  
Now, since it's also a bad idea to leave the field odd for longer than  
absolutely necessary (because readers will spin while we have it set),  
the expectation was that we'd treat these segments like spinlock critical  
sections, with only short, more or less straight-line, code in them.  
  
That was fine as originally designed, but commit 9029f4b37 broke it  
by inserting a significant amount of non-straight-line code into  
pgstat_bestart(), code that is very capable of throwing errors, not to  
mention taking a significant amount of time during which readers will spin.  
We have a report from Neeraj Kumar of readers actually locking up, which  
I suspect was due to an encoding conversion error in X509_NAME_to_cstring,  
though conceivably it was just a garden-variety OOM failure.  
  
Subsequent commits have loaded even more dubious code into pgstat_bestart's  
critical section (and commit fc70a4b0d deserves some kind of booby prize  
for managing to miss the critical section entirely, although the negative  
consequences seem minimal given that the PgBackendStatus entry should be  
seen by readers as inactive at that point).  
  
The right way to fix this mess seems to be to compute all these values  
into a local copy of the process' PgBackendStatus struct, and then just  
copy the data back within the critical section proper.  This plan can't  
be implemented completely cleanly because of the struct's heavy reliance  
on out-of-line strings, which we must initialize separately within the  
critical section.  But still, the critical section is far smaller and  
safer than it was before.  
  
In hopes of forestalling future errors of the same ilk, rename the  
macros for st_changecount management to make it more apparent that  
the writer-side macros create a critical section.  And to prevent  
the worst consequences if we nonetheless manage to mess it up anyway,  
adjust those macros so that they really are a critical section, ie  
they now bump CritSectionCount.  That doesn't add much overhead, and  
it guarantees that if we do somehow throw an error while the counter  
is odd, it will lead to PANIC and a database restart to reset shared  
memory.  
  
Back-patch to 9.5 where the problem was introduced.  
  
In HEAD, also fix an oversight in commit b0b39f72b: it failed to teach  
pgstat_read_current_status to copy st_gssstatus data from shared memory to  
local memory.  Hence, subsequent use of that data within the transaction  
would potentially see changing data that it shouldn't see.  
  
Discussion: https://postgr.es/m/CAPR3Wj5Z17=+eeyrn_ZDG3NQGYgMEOY6JV6Y-WRRhGgwc16U3Q@mail.gmail.com  

commit   : 239dcf8f15b70102ed18d1d8a020e4a7bbc2a6f9    
  
author   : Noah Misch <[email protected]>    
date     : Sat, 11 May 2019 00:22:38 -0700    
  
committer: Noah Misch <[email protected]>    
date     : Sat, 11 May 2019 00:22:38 -0700    

The buildfarm client uses TEMP_CONFIG to implement its extra_config  
setting.  Except for stats_temp_directory, extra_config now applies to  
TAP suites; extra_config values seen in the past month are compatible  
with this.  Back-patch to 9.6, where PostgresNode was introduced, so the  
buildfarm can rely on it sooner.  
  
Reviewed by Andrew Dunstan and Tom Lane.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : e16ab408f3db5ced50d84748b7a9f367ece93d3f    
  
author   : Michael Paquier <[email protected]>    
date     : Sat, 11 May 2019 13:01:07 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Sat, 11 May 2019 13:01:07 +0900    

When failing to reindex a table or an index, reindexdb would generate an  
extra error message related to a database failure, which is misleading.  
  
Backpatch all the way down, as this has been introduced by 85e9a5a0.  
  
Discussion: https://postgr.es/m/CAOBaU_Yo61RwNO3cW6WVYWwH7EYMPuexhKqufb2nFGOdunbcHw@mail.gmail.com  
Author: Julien Rouhaud  
Reviewed-by: Daniel Gustafsson, Álvaro Herrera, Tom Lane, Michael  
Paquier  
Backpatch-through: 9.4  

commit   : 803f90ab795b6bc170ba517cdd0dfddc85a5f961    
  
author   : Tom Lane <[email protected]>    
date     : Fri, 10 May 2019 14:56:41 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Fri, 10 May 2019 14:56:41 -0400    

There's a very old race condition in our code to see whether a pre-existing  
shared memory segment is still in use by a conflicting postmaster: it's  
possible for the other postmaster to remove the segment in between our  
shmctl() and shmat() calls.  It's a narrow window, and there's no risk  
unless both postmasters are using the same port number, but that's possible  
during parallelized "make check" tests.  (Note that while the TAP tests  
take some pains to choose a randomized port number, pg_regress doesn't.)  
If it does happen, we treated that as an unexpected case and errored out.  
  
To fix, allow EINVAL to be treated as segment-not-present, and the same  
for EIDRM on Linux.  AFAICS, the considerations here are basically  
identical to the checks for acceptable shmctl() failures, so I documented  
and coded it that way.  
  
While at it, adjust PGSharedMemoryAttach's API to remove its undocumented  
dependency on UsedShmemSegAddr in favor of passing the attach address  
explicitly.  This makes it easier to be sure we're using a null shmaddr  
when probing for segment conflicts (thus avoiding questions about what  
EINVAL means).  I don't think there was a bug there, but it required  
fragile assumptions about the state of UsedShmemSegAddr during  
PGSharedMemoryIsInUse.  
  
Commit c09850992 may have made this failure more probable by applying  
the conflicting-segment tests more often.  Hence, back-patch to all  
supported branches, as that was.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : e7eed0baa049ee2a1b06b7af10f7e4580a3a6cdd    
  
author   : Tom Lane <[email protected]>    
date     : Thu, 9 May 2019 16:52:49 -0400    
  
committer: Tom Lane <[email protected]>    
date     : Thu, 9 May 2019 16:52:49 -0400    

create_merge_append_plan failed to honor the CP_EXACT_TLIST flag:  
it would generate the expected targetlist but then it felt free to  
add resjunk sort targets to it.  This demonstrably leads to assertion  
failures in v11 and HEAD, and it's probably just accidental that we  
don't see the same in older branches.  I've not looked into whether  
there would be any real-world consequences in non-assert builds.  
In HEAD, create_append_plan has sprouted the same problem, so fix  
that too (although we do not have any test cases that seem able to  
reach that bug).  This is an oversight in commit 3fc6e2d7f which  
invented the CP_EXACT_TLIST flag, so back-patch to 9.6 where that  
came in.  
  
convert_subquery_pathkeys would create pathkeys for subquery output  
values if they match any EquivalenceClass known in the outer query  
and are available in the subquery's syntactic targetlist.  However,  
the second part of that condition is wrong, because such values might  
not appear in the subquery relation's reltarget list, which would  
mean that they couldn't be accessed above the level of the subquery  
scan.  We must check that they appear in the reltarget list, instead.  
This can lead to dropping knowledge about the subquery's sort  
ordering, but I believe it's okay, because any sort key that the  
outer query actually has any interest in would appear in the  
reltarget list.  
  
This second issue is of very long standing, but right now there's no  
evidence that it causes observable problems before 9.6, so I refrained  
from back-patching further than that.  We can revisit that choice if  
somebody finds a way to make it cause problems in older branches.  
(Developing useful test cases for these issues is really problematic;  
fixing convert_subquery_pathkeys removes the only known way to exhibit  
the create_merge_append_plan bug, and neither of the test cases added  
by this patch causes a problem in all branches, even when considering  
the issues separately.)  
  
The second issue explains bug #15795 from Suresh Kumar R ("could not  
find pathkey item to sort" with nested DISTINCT queries).  I stumbled  
across the first issue while investigating that.  
  
Discussion: https://postgr.es/m/[email protected]  

commit   : 25f12acd53f603a581d8bc89920037a811f12f82    
  
author   : Michael Paquier <[email protected]>    
date     : Thu, 9 May 2019 10:29:29 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Thu, 9 May 2019 10:29:29 +0900    

When running a batch of VACUUM or ANALYZE commands on a given database,  
there were cases where it is possible to have vacuumdb not report an  
error where it actually should, leading to incorrect status results.  
  
Author: Julien Rouhaud  
Reviewed-by: Amit Kapila, Michael Paquier  
Discussion: https://postgr.es/m/CAOBaU_ZuTwz7CtqLYJ1Ouuh272bTQPLN8b1bAPk0bCBm4PDMTQ@mail.gmail.com  
Backpatch-through: 9.5  

commit   : a9d5383db2e17a602ab6f9f0b4955623a8d444a6    
  
author   : Fujii Masao <[email protected]>    
date     : Thu, 9 May 2019 01:35:13 +0900    
  
committer: Fujii Masao <[email protected]>    
date     : Thu, 9 May 2019 01:35:13 +0900    

Previously it's documented that use of replication functions is  
restricted to superusers. This is true for the functions which  
use replication origin, but not for pg_logicl_emit_message() and  
functions which use replication slot. For example, not only  
superusers but also users with REPLICATION privilege is allowed  
to use the functions for replication slot. This commit fixes  
the documentation for the privileges required for those replication  
functions.  
  
Back-patch to 9.4 (all supported versions).  
  
Author: Matsumura Ryo  
Discussion: https://postgr.es/m/03040DFF97E6E54E88D3BFEE5F5480F74ABA6E16@G01JPEXMBYT04  

commit   : 1f3bcb4972009c8af7b71d1526559475a248f77a    
  
author   : Thomas Munro <[email protected]>    
date     : Mon, 6 May 2019 15:02:41 +1200    
  
committer: Thomas Munro <[email protected]>    
date     : Mon, 6 May 2019 15:02:41 +1200    

Commit c0985099, later adjusted by commit 4ab02e81, probed 0.0.0.0  
in addition to 127.0.0.1, for the benefit of Windows build farm  
animals.  It isn't really useful on Unix systems, and turned out to  
be a bit inconvenient to users of some corporate firewall software.  
Switch back to probing just 127.0.0.1 on non-Windows systems.  
  
Back-patch to 9.6, like the earlier changes.  
  
Discussion: https://postgr.es/m/CA%2BhUKG%2B21EPwfgs4m%2BtqyRtbVqkOUvP8QQ8sWk9%2Bh55Aub1H3A%40mail.gmail.com  

commit   : 2bc59f890100f9a90289f8ef10b9403294915ff8    
  
author   : Heikki Linnakangas <[email protected]>    
date     : Wed, 8 May 2019 09:32:34 +0300    
  
committer: Heikki Linnakangas <[email protected]>    
date     : Wed, 8 May 2019 09:32:34 +0300    

The flat file mechanism was removed in PostgreSQL 9.0.  

commit   : 64ad372346b358aeaf7fd7c6d913f636dc4af4db    
  
author   : Michael Paquier <[email protected]>    
date     : Tue, 7 May 2019 14:19:56 +0900    
  
committer: Michael Paquier <[email protected]>    
date     : Tue, 7 May 2019 14:19:56 +0900    

This code was broken as of 582edc3, and is most likely not used anymore.  
Note that pg_dump supports servers down to 8.0, and psql has code to  
support servers down to 7.4.  
  
Author: Julien Rouhaud  
Reviewed-by: Tom Lane  
Discussion: https://postgr.es/m/CAOBaU_Y5y=zo3+2gf+2NJC1pvMYPcbRXoQaPXx=U7+C8Qh4CzQ@mail.gmail.com