ForgetBackgroundWorker lacked any memory barrier at all, while
BackgroundWorkerStateChange had one but unaccountably did
additional manipulation of the slot after the barrier. AFAICS,
the rule must be that the barrier is immediately before setting
or clearing slot->in_use.
It looks like back in 9.6 when ForgetBackgroundWorker was first
written, there might have been some case for not needing a
barrier there, but I'm not very convinced of that --- the fact
that the load of bgw_notify_pid is in the caller doesn't seem
to guarantee no memory ordering problem. So patch 9.6 too.
It's likely that this doesn't fix any observable bug on Intel
hardware, but machines with weaker memory ordering rules could
have problems here.
Discussion: https://postgr.es/m/4046084.1620244003@sss.pgh.pa.us
Formerly we just relied on operator classes that assert longValuesOK
to eventually shorten the leaf value enough to fit on an index page.
That fails since the introduction of INCLUDE-column support (commit
09c1c6ab4), because the INCLUDE columns might alone take up more
than a page, meaning no amount of leaf-datum compaction will get
the job done. At least with spgtextproc.c, that leads to an infinite
loop, since spgtextproc.c won't throw an error for not being able
to shorten the leaf datum anymore.
To fix without breaking cases that would otherwise work, add logic
to spgdoinsert() to verify that the leaf tuple size is decreasing
after each "choose" step. Some opclasses might not decrease the
size on every single cycle, and in any case, alignment roundoff
of the tuple size could obscure small gains. Therefore, allow
up to 10 cycles without additional savings before throwing an
error. (Perhaps this number will need adjustment, but it seems
quite generous right now.)
As long as we've developed this logic, let's back-patch it.
The back branches don't have INCLUDE columns to worry about, but
this seems like a good defense against possible bugs in operator
classes. We already know that an infinite loop here is pretty
unpleasant, so having a defense seems to outweigh the risk of
breaking things. (Note that spgtextproc.c is actually the only
known opclass with longValuesOK support, so that this is all moot
for known non-core opclasses anyway.)
Per report from Dilip Kumar.
Discussion: https://postgr.es/m/CAFiTN-uxP_soPhVG840tRMQTBmtA_f_Y8N51G7DKYYqDh7XN-A@mail.gmail.com
Knowing that a buggy opclass could cause an infinite insertion loop,
spgdoinsert() intended to allow its loop to be interrupted by query
cancel. However, that never actually worked, because in iterations
after the first, we'd be holding buffer lock(s) which would cause
InterruptHoldoffCount to be positive, preventing servicing of the
interrupt.
To fix, check if an interrupt is pending, and if so fall out of
the insertion loop and service the interrupt after we've released
the buffers. If it was indeed a query cancel, that's the end of
the matter. If it was a non-canceling interrupt reason, make use
of the existing provision to retry the whole insertion. (This isn't
as wasteful as it might seem, since any upper-level index tuples we
already created should be usable in the next attempt.)
While there's no known instance of such a bug in existing release
branches, it still seems like a good idea to back-patch this to
all supported branches, since the behavior is fairly nasty if a
loop does happen --- not only is it uncancelable, but it will
quickly consume memory to the point of an OOM failure. In any
case, this code is certainly not working as intended.
Per report from Dilip Kumar.
Discussion: https://postgr.es/m/CAFiTN-uxP_soPhVG840tRMQTBmtA_f_Y8N51G7DKYYqDh7XN-A@mail.gmail.com
Split up CHECK_FOR_INTERRUPTS() to provide an additional macro
INTERRUPTS_PENDING_CONDITION(), which just tests whether an
interrupt is pending without attempting to service it. This is
useful in situations where the caller knows that interrupts are
blocked, and would like to find out if it's worth the trouble
to unblock them.
Also add INTERRUPTS_CAN_BE_PROCESSED(), which indicates whether
CHECK_FOR_INTERRUPTS() can be relied on to clear the pending interrupt.
This commit doesn't actually add any uses of the new macros,
but a follow-on bug fix will do so. Back-patch to all supported
branches to provide infrastructure for that fix.
Alvaro Herrera and Tom Lane
Discussion: https://postgr.es/m/20210513155351.GA7848@alvherre.pgsql
The worker.c global wrconn is only meant to be used by logical apply/
tablesync workers, but there are other variables with the same name. To
reduce future confusion rename the global from "wrconn" to
"LogRepWorkerWalRcvConn".
While this is just cosmetic, it seems better to backpatch it all the way
back to 10 where this code appeared, to avoid future backpatching
issues.
Author: Peter Smith <smithpb2250@gmail.com>
Discussion: https://postgr.es/m/CAHut+Pu7Jv9L2BOEx_Z0UtJxfDevQSAUW2mJqWU+CtmDrEZVAg@mail.gmail.com
It's unusual to have any resjunk columns in an ON CONFLICT ... UPDATE
list, but it can happen when MULTIEXPR_SUBLINK SubPlans are present.
If it happens, the ON CONFLICT UPDATE code path would end up storing
tuples that include the values of the extra resjunk columns. That's
fairly harmless in the short run, but if new columns are added to
the table then the values would become accessible, possibly leading
to malfunctions if they don't match the datatypes of the new columns.
This had escaped notice through a confluence of missing sanity checks,
including
* There's no cross-check that a tuple presented to heap_insert or
heap_update matches the table rowtype. While it's difficult to
check that fully at reasonable cost, we can easily add assertions
that there aren't too many columns.
* The output-column-assignment cases in execExprInterp.c lacked
any sanity checks on the output column numbers, which seems like
an oversight considering there are plenty of assertion checks on
input column numbers. Add assertions there too.
* We failed to apply nodeModifyTable's ExecCheckPlanOutput() to
the ON CONFLICT UPDATE tlist. That wouldn't have caught this
specific error, since that function is chartered to ignore resjunk
columns; but it sure seems like a bad omission now that we've seen
this bug.
In HEAD, the right way to fix this is to make the processing of
ON CONFLICT UPDATE tlists work the same as regular UPDATE tlists
now do, that is don't add "SET x = x" entries, and use
ExecBuildUpdateProjection to evaluate the tlist and combine it with
old values of the not-set columns. This adds a little complication
to ExecBuildUpdateProjection, but allows removal of a comparable
amount of now-dead code from the planner.
In the back branches, the most expedient solution seems to be to
(a) use an output slot for the ON CONFLICT UPDATE projection that
actually matches the target table, and then (b) invent a variant of
ExecBuildProjectionInfo that can be told to not store values resulting
from resjunk columns, so it doesn't try to store into nonexistent
columns of the output slot. (We can't simply ignore the resjunk columns
altogether; they have to be evaluated for MULTIEXPR_SUBLINK to work.)
This works back to v10. In 9.6, projections work much differently and
we can't cheaply give them such an option. The 9.6 version of this
patch works by inserting a JunkFilter when it's necessary to get rid
of resjunk columns.
In addition, v11 and up have the reverse problem when trying to
perform ON CONFLICT UPDATE on a partitioned table. Through a
further oversight, adjust_partition_tlist() discarded resjunk columns
when re-ordering the ON CONFLICT UPDATE tlist to match a partition.
This accidentally prevented the storing-bogus-tuples problem, but
at the cost that MULTIEXPR_SUBLINK cases didn't work, typically
crashing if more than one row has to be updated. Fix by preserving
resjunk columns in that routine. (I failed to resist the temptation
to add more assertions there too, and to do some minor code
beautification.)
Per report from Andres Freund. Back-patch to all supported branches.
Security: CVE-2021-32028
While we were (mostly) careful about ensuring that the dimensions of
arrays aren't large enough to cause integer overflow, the lower bound
values were generally not checked. This allows situations where
lower_bound + dimension overflows an integer. It seems that that's
harmless so far as array reading is concerned, except that array
elements with subscripts notionally exceeding INT_MAX are inaccessible.
However, it confuses various array-assignment logic, resulting in a
potential for memory stomps.
Fix by adding checks that array lower bounds aren't large enough to
cause lower_bound + dimension to overflow. (Note: this results in
disallowing cases where the last subscript position would be exactly
INT_MAX. In principle we could probably allow that, but there's a lot
of code that computes lower_bound + dimension and would need adjustment.
It seems doubtful that it's worth the trouble/risk to allow it.)
Somewhat independently of that, array_set_element() was careless
about possible overflow when checking the subscript of a fixed-length
array, creating a different route to memory stomps. Fix that too.
Security: CVE-2021-32027
This patch replaces use of the global "wrconn" variable in
AlterSubscription_refresh with a local variable of the same name, making
it consistent with other functions in subscriptioncmds.c (e.g.
DropSubscription).
The global wrconn is only meant to be used for logical apply/tablesync worker.
Abusing it this way is known to cause trouble if an apply worker
manages to do a subscription refresh, such as reported by Jeremy Finzel
and diagnosed by Andres Freund back in November 2020, at
https://www.postgresql.org/message-id/20201111215820.qihhrz7fayu6myfi@alap3.anarazel.de
Backpatch to 10. In branch master, also move the connection establishment
to occur outside the PG_TRY block; this way we can remove a test for NULL in
PG_FINALLY, and it also makes the code more consistent with similar code in
the same file.
Author: Peter Smith <peter.b.smith@fujitsu.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Japin Li <japinli@hotmail.com>
Discussion: https://postgr.es/m/CAHut+Pu7Jv9L2BOEx_Z0UtJxfDevQSAUW2mJqWU+CtmDrEZVAg@mail.gmail.com
When ALTER TABLE .. ALTER CONSTRAINT changes deferrability properties
changed in a partitioned table, we failed to propagate those changes
correctly to partitions and to triggers. Repair by adding a recursion
mechanism to affect all derived constraints and all derived triggers.
(In particular, recurse to partitions even if their respective parents
are already in the desired state: it is possible for the partitions to
have been altered individually.) Because foreign keys involve tables in
two sides, we cannot use the standard ALTER TABLE recursion mechanism,
so we invent our own by following pg_constraint.conparentid down.
When ALTER TABLE .. ALTER CONSTRAINT is invoked on the derived
pg_constraint object that's automaticaly created in a partition as a
result of a constraint added to its parent, raise an error instead of
pretending to work and then failing to modify all the affected triggers.
Before this commit such a command would be allowed but failed to affect
all triggers, so it would silently misbehave. (Restoring dumps of
existing databases is not affected, because pg_dump does not produce
anything for such a derived constraint anyway.)
Add some tests for the case.
Backpatch to 11, where foreign key support was added to partitioned
tables by commit 3de241dba8. (A related change is commit f56f8f8da6
in pg12 which added support for FKs *referencing* partitioned tables;
this is what forces us to use an ad-hoc recursion mechanism for this.)
Diagnosed by Tom Lane from bug report from Ron L Johnson. As of this
writing, no reviews were offered.
Discussion: https://postgr.es/m/75fe0761-a291-86a9-c8d8-4906da077469@gmail.com
Discussion: https://postgr.es/m/3144850.1607369633@sss.pgh.pa.us
The OID of the constraint is used instead of the OID of the trigger --
an easy mistake to make. Apparently the object-alter hooks are not very
well tested :-(
Backpatch to 12, where this typo was introduced by 578b229718
Discussion: https://postgr.es/m/20210503231633.GA6994@alvherre.pgsql
When running ALTER TABLE t2 INHERIT t1, we must check that columns in
t2 that correspond to a generated column in t1 are also generated and
have the same generation expression. Otherwise, this would allow
creating setups that a normal CREATE TABLE sequence would not allow.
Discussion: https://www.postgresql.org/message-id/22de27f6-7096-8d96-4619-7b882932ca25@2ndquadrant.com
Reject aggregates, window functions, and procedures. Aggregates
failed anyway, though with a somewhat obscure error message.
Window functions would hit an Assert or null-pointer dereference.
Procedures seemed to work as long as you didn't try to do
transaction control, but (a) transaction control is sort of the
point of a procedure, and (b) it's not entirely clear that no
bugs lurk in that path. Given the lack of testing of this area,
it seems safest to be conservative in what we support.
Also reject proretset functions, as the fastpath protocol can't
support returning a set.
Also remove an easily-triggered assertion that the given OID
isn't 0; the subsequent lookups can handle that case themselves.
Per report from Theodor-Arsenij Larionov-Trichkin.
Back-patch to all supported branches. (The procedure angle
only applies in v11+, of course.)
Discussion: https://postgr.es/m/2039442.1615317309@sss.pgh.pa.us
Commits 29aeda6e4 et al closed up some oversights involving not checking
for non-upgradable types within container types, such as arrays and
ranges. However, I only looked at version.c, failing to notice that
there were substantially-equivalent tests in check.c. (The division
of responsibility between those files is less than clear...)
In addition, because genbki.pl does not guarantee that auto-generated
rowtype OIDs will hold still across versions, we need to consider that
the composite type associated with a system catalog or view is
non-upgradable. It seems unlikely that someone would have a user
column declared that way, but if they did, trying to read it in another
PG version would likely draw "no such pg_type OID" failures, thanks
to the type OID embedded in composite Datums.
To support the composite and reg*-type cases, extend the recursive
query that does the search to allow any base query that returns
a column of pg_type OIDs, rather than limiting it to exactly one
starting type.
As before, back-patch to all supported branches.
Discussion: https://postgr.es/m/2798740.1619622555@sss.pgh.pa.us
Attempting to use this function with event triggers failed, as, since
its introduction in a676201, this code has never associated an object
name with event triggers. This addresses the failure by adding the
event trigger name to the set defining its object address.
Note that regression tests are added within event_trigger and not
object_address to avoid issues with concurrent connections in parallel
schedules.
Author: Joel Jacobson
Discussion: https://postgr.es/m/3c905e77-a026-46ae-8835-c3f6cd1d24c8@www.fastmail.com
Backpatch-through: 9.6
Adopt a more consistent policy about what slot-type-specific
getsysattr functions should do when system attributes are not
available. To wit, they should all throw the same user-oriented
error, rather than variously crashing or emitting developer-oriented
messages.
This closes a identifiable problem in commits a71cfc56b and
3fb93103a (in v13 and v12), so back-patch into those branches,
along with a test case to try to ensure we don't break it again.
It is not known that any of the former crash cases are reachable
in HEAD, but this seems like a good safety improvement in any case.
Discussion: https://postgr.es/m/141051591267657@mail.yandex.ru
If the source and destination partitions don't have identical
rowtypes (for example, one has dropped columns the other lacks),
then the planSlot contents will be different because of that.
If the query has a RETURNING list that tries to return resjunk
columns out of the planSlot, that is columns from tables that
were joined to the target table, we'd get errors or wrong answers.
That's because we used the RETURNING list generated for the
destination partition, which expects a planSlot matching that
partition's subplan.
The most practical fix seems to be to convert the updated destination
tuple back to the source partition's rowtype, and then apply the
RETURNING list generated for the source partition. This avoids making
fragile assumptions about whether the per-subpartition subplans
generated all the resjunk columns in the same order.
This has been broken since v11 introduced cross-partition UPDATE.
The lack of field complaints shows that non-identical partitions
aren't a common case; therefore, don't stress too hard about
making the conversion efficient.
There's no such bug in HEAD, because commit 86dc90056 got rid of
per-target-relation variance in the contents of the planSlot.
Hence, patch v11-v13 only.
Amit Langote and Etsuro Fujita, small changes by me
Discussion: https://postgr.es/m/CA+HiwqE_UK1jTSNrjb8mpTdivzd3dum6mK--xqKq0Y9VmfwWQA@mail.gmail.com
In order to avoid getting old logfile contents certain functions in
PostgresNode were doing one of two things. On Windows it rotated the
logfile and restarted the server, while elsewhere it truncated the log
file. Both of these are unnecessary. We borrow from the buildfarm which
does this instead: note the size of the logfile before we start, and
then when fetching the logfile skip to that position before accumulating
contents. This is spelled differently on Windows but the effect is the
same. This is largely centralized in TestLib's slurp_file function,
which has a new optional parameter, the offset to skip to before
starting to reading the file. Code in the client becomes much neater.
Backpatch to all live branches.
Michael Paquier, slightly modified by me.
Discussion: https://postgr.es/m/YHajnhcMAI3++pJL@paquier.xyz
Most GUC check hooks that inspect database state have special checks
that prevent them from throwing hard errors for state-dependent issues
when source == PGC_S_TEST. This allows, for example,
"ALTER DATABASE d SET default_text_search_config = foo" when the "foo"
configuration hasn't been created yet. Without this, we have problems
during dump/reload or pg_upgrade, because pg_dump has no idea about
possible dependencies of GUC values and can't ensure a safe restore
ordering.
However, check_role() and check_session_authorization() hadn't gotten
the memo about that, and would throw hard errors anyway. It's not
entirely clear what is the use-case for "ALTER ROLE x SET role = y",
but we've now heard two independent complaints about that bollixing
an upgrade, so apparently some people are doing it.
Hence, fix these two functions to act more like other check hooks
with similar needs. (But I did not change their insistence on
being inside a transaction, as it's still not apparent that setting
either GUC from the configuration file would be wise.)
Also fix check_temp_buffers, which had a different form of the disease
of making state-dependent checks without any exception for PGC_S_TEST.
A cursory survey of other GUC check hooks did not find any more issues
of this ilk. (There are a lot of interdependencies among
PGC_POSTMASTER and PGC_SIGHUP GUCs, which may be a bad idea, but
they're not relevant to the immediate concern because they can't be
set via ALTER ROLE/DATABASE.)
Per reports from Charlie Hornsby and Nathan Bossart. Back-patch
to all supported branches.
Discussion: https://postgr.es/m/HE1P189MB0523B31598B0C772C908088DB7709@HE1P189MB0523.EURP189.PROD.OUTLOOK.COM
Discussion: https://postgr.es/m/20160711223641.1426.86096@wrigleys.postgresql.org
Previously, get_cached_rowtype() cached a pointer to a reference-counted
tuple descriptor from the typcache, relying on the ExprContextCallback
mechanism to release the tupdesc refcount when the expression tree
using the tupdesc was destroyed. This worked fine when it was designed,
but the introduction of within-DO-block COMMITs broke it. The refcount
is logged in a transaction-lifespan resource owner, but plpgsql won't
destroy simple expressions made within the DO block (before its first
commit) until the DO block is exited. That results in a warning about
a leaked tupdesc refcount when the COMMIT destroys the original resource
owner, and then an error about the active resource owner not holding a
matching refcount when the expression is destroyed.
To fix, get rid of the need to have a shutdown callback at all, by
instead caching a pointer to the relevant typcache entry. Those
survive for the life of the backend, so we needn't worry about the
pointer becoming stale. (For registered RECORD types, we can still
cache a pointer to the tupdesc, knowing that it won't change for the
life of the backend.) This mechanism has been in use in plpgsql
and expandedrecord.c since commit 4b93f5799, and seems to work well.
This change requires modifying the ExprEvalStep structs used by the
relevant expression step types, which is slightly worrisome for
back-patching. However, there seems no good reason for extensions
to be familiar with the details of these particular sub-structs.
Per report from Rohit Bhogate. Back-patch to v11 where within-DO-block
COMMITs became a thing.
Discussion: https://postgr.es/m/CAAV6ZkQRCVBh8qAY+SZiHnz+U+FqAGBBDaDTjF2yiKa2nJSLKg@mail.gmail.com
heap_update needs to clear any existing "all visible" flag on
the old tuple's page (and on the new page too, if different).
Per coding rules, to do this it must acquire pin on the appropriate
visibility-map page while not holding exclusive buffer lock;
which creates a race condition since someone else could set the
flag whenever we're not holding the buffer lock. The code is
supposed to handle that by re-checking the flag after acquiring
buffer lock and retrying if it became set. However, one code
path through heap_update itself, as well as one in its subroutine
RelationGetBufferForTuple, failed to do this. The end result,
in the unlikely event that a concurrent VACUUM did set the flag
while we're transiently not holding lock, is a non-recurring
"PANIC: wrong buffer passed to visibilitymap_clear" failure.
This has been seen a few times in the buildfarm since recent VACUUM
changes that added code paths that could set the all-visible flag
while holding only exclusive buffer lock. Previously, the flag
was (usually?) set only after doing LockBufferForCleanup, which
would insist on buffer pin count zero, thus preventing the flag
from becoming set partway through heap_update. However, it's
clear that it's heap_update not VACUUM that's at fault here.
What's less clear is whether there is any hazard from these bugs
in released branches. heap_update is certainly violating API
expectations, but if there is no code path that can set all-visible
without a cleanup lock then it's only a latent bug. That's not
100% certain though, besides which we should worry about extensions
or future back-patch fixes that could introduce such code paths.
I chose to back-patch to v12. Fixing RelationGetBufferForTuple
before that would require also back-patching portions of older
fixes (notably 0d1fe9f74), which is more code churn than seems
prudent to fix a hypothetical issue.
Discussion: https://postgr.es/m/2247102.1618008027@sss.pgh.pa.us
With the Oracle Developer Studio 12.6 compiler, #line directives alter
the current source file location for purposes of #include "..."
directives. Hence, a VPATH build failed with 'cannot find include file:
"specscanner.c"'. With two exceptions, parser-containing directories
already add "-I. -I$(srcdir)"; eliminate the exceptions. Back-patch to
9.6 (all supported versions).
There are hacks in parse_coerce.c to push down a requested coercion
to below any CollateExpr that may appear. However, we did that even
if the requested data type is non-collatable, leading to an invalid
expression tree in which CollateExpr is applied to a non-collatable
type. The fix is just to drop the CollateExpr altogether, reasoning
that it's useless.
This bug is ten years old, dating to the original addition of
COLLATE support. The lack of field complaints suggests that there
aren't a lot of user-visible consequences. We noticed the problem
because it would trigger an assertion in DefineVirtualRelation if
the invalid structure appears as an output column of a view; however,
in a non-assert build, you don't see a crash just a (subtly incorrect)
complaint about applying collation to a non-collatable type. I found
that by putting the incorrect structure further down in a view, I could
make a view definition that would fail dump/reload, per the added
regression test case. But CollateExpr doesn't do anything at run-time,
so this likely doesn't lead to any really exciting consequences.
Per report from Yulin Pei. Back-patch to all supported branches.
Discussion: https://postgr.es/m/HK0PR01MB22744393C474D503E16C8509F4709@HK0PR01MB2274.apcprd01.prod.exchangelabs.com
Using Roman numbers (via "RM" or "rm") for a conversion to calculate a
number of months has never considered the case of negative numbers,
where a conversion could easily cause out-of-bound memory accesses. The
conversions in themselves were not completely consistent either, as
specifying 12 would result in NULL, but it should mean XII.
This commit reworks the conversion calculation to have a more
consistent behavior:
- If the number of months and years is 0, return NULL.
- If the number of months is positive, return the exact month number.
- If the number of months is negative, do a backward calculation, with
-1 meaning December, -2 November, etc.
Reported-by: Theodor Arsenij Larionov-Trichkin
Author: Julien Rouhaud
Discussion: https://postgr.es/m/16953-f255a18f8c51f1d5@postgresql.org
backpatch-through: 9.6
The code in bringetbitmap() simply added the whole matching page range
to the TID bitmap, as determined by pages_per_range, even if some of the
pages were beyond the end of the heap. The query then might fail with
an error like this:
ERROR: could not open file "base/20176/20228.2" (target block
262144): previous segment is only 131021 blocks
In this case, the relation has 262093 pages (131072 and 131021 pages),
but we're trying to acess block 262144, i.e. first block of the 3rd
segment. At that point _mdfd_getseg() notices the preceding segment is
incomplete, and fails.
Hitting this in practice is rather unlikely, because:
* Most indexes use power-of-two ranges, so segments and page ranges
align perfectly (segment end is also a page range end).
* The table size has to be just right, with the last segment being
almost full - less than one page range from full segment, so that the
last page range actually crosses the segment boundary.
* Prefetch has to be enabled. The regular page access checks that
pages are not beyond heap end, but prefetch does not. On older
releases (before 12) the execution stops after hitting the first
non-existent page, so the prefetch distance has to be sufficient
to reach the first page in the next segment to trigger the issue.
Since 12 it's enough to just have prefetch enabled, the prefetch
distance does not matter.
Fixed by not adding non-existent pages to the TID bitmap. Backpatch
all the way back to 9.6 (BRIN indexes were introduced in 9.5, but that
release is EOL).
Backpatch-through: 9.6
Instead of writing a query to psql's stdin, which can cause a failure
where psql exits before writing, reporting a write failure with a broken
pipe, this changes the logic to use -c. This was not seen in the
buildfarm as no animals with a sensitive environment are running the
kerberos tests, but let's be safe.
HEAD is able to handle the situation as of 6d41dd0 for all the test
suites doing connection checks. f44b9b6 has fixed the same problem for
the LDAP tests.
Discussion: https://postgr.es/m/YGu7ceWAiSNQDgH5@paquier.xyz
Backpatch-through: 11
Maxim Orlov reported that the shutdown of standby server could result in
the following assertion failure. The cause of this issue was that,
when the shutdown caused the startup process to exit, recovery-time
transaction tracking was not shut down even if it's already initialized,
and some locks the tracked transactions were holding could not be released.
At this situation, if other process was invoked and the PGPROC entry that
the startup process used was assigned to it, it found such unreleased locks
and caused the assertion failure, during the initialization of it.
TRAP: FailedAssertion("SHMQueueEmpty(&(MyProc->myProcLocks[i]))"
This commit fixes this issue by making the startup process shut down
transaction tracking and release all locks, at the exit of it.
Back-patch to all supported branches.
Reported-by: Maxim Orlov
Author: Fujii Masao
Reviewed-by: Maxim Orlov
Discussion: https://postgr.es/m/ad4ce692cc1d89a093b471ab1d969b0b@postgrespro.ru
spg_box_quad_leaf_consistent unconditionally returned the leaf
datum as leafValue, even though in its usage for poly_ops that
value is of completely the wrong type.
In versions before 12, that was harmless because the core code did
nothing with leafValue in non-index-only scans ... but since commit
2a6368343, if we were doing a KNN-style scan, spgNewHeapItem would
unconditionally try to copy the value using the wrong datatype
parameters. Said copying is a waste of time and space if we're not
going to return the data, but it accidentally failed to fail until
I fixed the datatype confusion in ac9099fc1.
Hence, change spgNewHeapItem to not copy the datum unless we're
actually going to return it later. This saves cycles and dodges
the question of whether lossy opclasses are returning the right
type. Also change spg_box_quad_leaf_consistent to not return
data that might be of the wrong type, as insurance against
somebody introducing a similar bug into the core code in future.
It seems like a good idea to back-patch these two changes into
v12 and v13, although I'm afraid to change spgNewHeapItem's
mistaken idea of which datatype to use in those branches.
Per buildfarm results from ac9099fc1.
Discussion: https://postgr.es/m/3728741.1617381471@sss.pgh.pa.us
pg_checksums uses two counters, total size and current size,
to calculate the progress. Previously the progress that
pg_checksums reported could not reach 100% at the end.
The cause of this issue was that the sizes of only pages excluding
new ones in each file were counted as the current size
while the size of each file is counted as the total size.
That is, the total size of all new pages could be reported
as the difference between the total size and current size.
This commit fixes this issue by making pg_checksums count
the sizes of all pages including new ones in each file as
the current size.
Back-patch to v12 where progress reporting was added to pg_checksums.
Reported-by: Shinya Kato
Author: Shinya Kato
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/TYAPR01MB289656B1ACA0A5E7CAD07BE3C47A9@TYAPR01MB2896.jpnprd01.prod.outlook.com
This test has been using a simple VACUUM with pg_relation_size() to
check if a relation gets physically truncated or not, but forgot the
fact that some concurrent activity, like checkpoint buffer writes, could
cause some pages to be skipped. The second test enabling
vacuum_truncate could fail, seeing a non-empty relation. The first test
would not have failed, but could finish by testing a behavior different
than the one aimed for. Both tests gain a FREEZE option, to make the
vacuums more aggressive and prevent page skips.
This is similar to the issues fixed in c2dc1a7.
Author: Arseny Sher
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/87tuotr2hh.fsf@ars-thinkpad
backpatch-through: 12
Despite the clear comments pointing out that the duplicative code
segments in ReadHead() and _discoverArchiveFormat() needed to be
in sync, they were not: the latter did not bother to apply any of
the sanity checks in the former. We'd missed noticing this partly
because none of those checks would fail in scenarios we customarily
test, and partly because the oversight would be masked if both
segments execute, which they would in cases other than needing to
autodetect the format of a non-seekable stdin source. However,
in a case meeting all these requirements --- for example, trying
to read a newer-than-supported archive format from non-seekable
stdin --- pg_restore missed applying the version check and would
likely dump core or otherwise misbehave.
The whole thing is silly anyway, because there seems little reason
to duplicate the logic beyond the one-line verification that the
file starts with "PGDMP". There seems to have been an undocumented
assumption that multiple major formats (major enough to require
separate reader modules) would nonetheless share the first half-dozen
fields of the custom-format header. This seems unlikely, so let's
fix it by just nuking the duplicate logic in _discoverArchiveFormat().
Also get rid of the pointless attempt to seek back to the start of
the file after successful autodetection. That wastes cycles and
it means we have four behaviors to verify not two.
Per bug #16951 from Sergey Koposov. This has been broken for
decades, so back-patch to all supported versions.
Discussion: https://postgr.es/m/16951-a4dd68cf0de23048@postgresql.org
When estimating the number of groups using extended statistics, the code
was discarding information about system attributes. This led to strange
situation that
SELECT 1 FROM t GROUP BY ctid;
could have produced higher estimate (equal to pg_class.reltuples) than
SELECT 1 FROM t GROUP BY a, b, ctid;
with extended statistics on (a,b). Fixed by retaining information about
the system attribute.
Backpatch all the way to 10, where extended statistics were introduced.
Author: Tomas Vondra
Backpatch-through: 10
I introduced this duplicate code in commit 8b08f7d482 for no good
reason. Remove it, and backpatch to 11 where it was introduced.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Previously the WAL replay of COMMIT_TS_SETTS record called
TransactionTreeSetCommitTsData() with the argument write_xlog=true,
which generated and wrote new COMMIT_TS_SETTS record.
This should not be acceptable because it's during recovery.
This commit fixes the WAL replay of COMMIT_TS_SETTS record
so that it calls TransactionTreeSetCommitTsData() with write_xlog=false
and doesn't generate new WAL during recovery.
Back-patch to all supported branches.
Reported-by: lx zou <zoulx1982@163.com>
Author: Fujii Masao
Reviewed-by: Alvaro Herrera
Discussion: https://postgr.es/m/16931-620d0f2fdc6108f1@postgresql.org
Jasen Betts reported yet another unintended side effect of commit
85c54287a: reconnecting with "\c service=whatever" did not have the
expected results. The reason is that starting from the output of
PQconndefaults() effectively allows environment variables (such
as PGPORT) to override entries in the service file, whereas the
normal priority is the other way around.
Not using PQconndefaults at all would require yet a third main code
path in do_connect's parameter setup, so I don't really want to fix
it that way. But we can have the logic effectively ignore all the
default values for just a couple more lines of code.
This patch doesn't change the behavior for "\c -reuse-previous=on
service=whatever". That remains significantly different from before
85c54287a, because many more parameters will be re-used, and thus
not be possible for service entries to replace. But I think this
is (mostly?) intentional. In any case, since libpq does not report
where it got parameter values from, it's hard to do differently.
Per bug #16936 from Jasen Betts. As with the previous patches,
back-patch to all supported branches. (9.5 is unfortunately now
out of support, so this won't get fixed there.)
Discussion: https://postgr.es/m/16936-3f524322a53a29f0@postgresql.org
A couple error messages and comments used 'statistic kind', not the
correct 'statistics kind'. Fix and backpatch all the way back to 10,
where extended statistics were introduced.
Backpatch-through: 10
pg_waldump --stats=record identifies a record by a combination
of the RmgrId and the four bits of the xl_info field of the record.
But XACT records use the first bit of those four bits for an optional
flag variable, and the following three bits for the opcode to
identify a record. So previously the same type of XACT record
could have different four bits (three bits are the same but the
first one bit is different), and which could cause
pg_waldump --stats=record to show two lines of per-record statistics
for the same XACT record. This is a bug.
This commit changes pg_waldump --stats=record so that it processes
only XACT record differently, i.e., filters the opcode out of xl_info
and uses a combination of the RmgrId and those three bits as
the identifier of a record, only for XACT record. For other records,
the four bits of the xl_info field are still used.
Back-patch to all supported branches.
Author: Kyotaro Horiguchi
Reviewed-by: Shinya Kato, Fujii Masao
Discussion: https://postgr.es/m/2020100913412132258847@highgo.ca
The test added by 595b9cb forgot that on Windows it is necessary to set
up pg_hba.conf (see PostgresNode::set_replication_conf) with a specific
entry or base backups fail. Any node that requires to support
replication just needs to pass down allows_streaming at initialization.
This updates the test to do so. Simplify things a bit while on it.
Per buildfarm member fairywren. Any Windows hosts running this test
would have failed, and I have reproduced the problem as well.
Backpatch-through: 10
Any transactions found as still prepared by a checkpoint have their
state data read from the WAL records generated by PREPARE TRANSACTION
before being moved into their new location within pg_twophase/. While
reading such records, the WAL reader uses the callback
read_local_xlog_page() to read a page, that is shared across various
parts of the system. This callback, since 1148e22a, has introduced an
update of ThisTimeLineID when reading a record while in recovery, which
is potentially helpful in the context of cascading WAL senders.
This update of ThisTimeLineID interacts badly with the checkpointer if a
promotion happens while some 2PC data is read from its record, as, by
changing ThisTimeLineID, any follow-up WAL records would be written to
an timeline older than the promoted one. This results in consistency
issues. For instance, a subsequent server restart would cause a failure
in finding a valid checkpoint record, resulting in a PANIC, for
instance.
This commit changes the code reading the 2PC data to reset the timeline
once the 2PC record has been read, to prevent messing up with the static
state of the checkpointer. It would be tempting to do the same thing
directly in read_local_xlog_page(). However, based on the discussion
that has led to 1148e22a, users may rely on the updates of
ThisTimeLineID when a WAL record page is read in recovery, so changing
this callback could break some cases that are working currently.
A TAP test reproducing the issue is added, relying on a PITR to
precisely trigger a promotion with a prepared transaction still
tracked.
Per discussion with Heikki Linnakangas, Kyotaro Horiguchi, Fujii Masao
and myself.
Author: Soumyadeep Chakraborty, Jimmy Yih, Kevin Yeap
Discussion: https://postgr.es/m/CAE-ML+_EjH_fzfq1F3RJ1=XaaNG=-Jz-i3JqkNhXiLAsM3z-Ew@mail.gmail.com
Backpatch-through: 10
While back-patching e0e569e1d, I noted that there were some other
places where we ought to be applying DH_free(); namely, where we
load some DH parameters from a file and then reject them as not
being sufficiently secure. While it seems really unlikely that
anybody would hit these code paths in production, let alone do
so repeatedly, let's fix it for consistency.
Back-patch to v10 where this code was introduced.
Discussion: https://postgr.es/m/16160-18367e56e9a28264@postgresql.org
When loading DH parameters used for the generation of ephemeral DH keys
in the backend, the code has never bothered releasing the memory used
for the DH information loaded from a file or from libpq's default. This
commit makes sure that the information is properly free()'d.
Back-patch of e0e569e1d. We originally thought the leak was minor and
not worth back-patching, but Jelte Fennema pointed out that repeated
SIGHUP's can result in very serious bloat of the postmaster, which is
then multiplied by being duplicated into eadh forked child.
Back-patch to v10; the code looked different before c0a15e07c,
and didn't have a leak in the actually-live code paths.
Michael Paquier
Discussion: https://postgr.es/m/16160-18367e56e9a28264@postgresql.org
We leaked the error report from PQconninfoParse, when there was
one. It seems unlikely that real usage patterns would repeat
the failure often enough to create serious bloat, but let's
back-patch anyway to keep the code similar in all branches.
Found via valgrind testing.
Back-patch to v10 where this code was added.
Discussion: https://postgr.es/m/3816764.1616104288@sss.pgh.pa.us
Because guc.c prefers to keep all its string values in malloc'd
not palloc'd storage, it has to be more careful than usual to
avoid leaks. Error exits out of string GUC hook checks failed
to clear the proposed value string, and error exits out of
ProcessGUCArray() failed to clear the malloc'd results of
ParseLongOption().
Found via valgrind testing.
This problem is ancient, so back-patch to all supported branches.
Discussion: https://postgr.es/m/3816764.1616104288@sss.pgh.pa.us
The text search cache mechanisms assume that we can clean up
an invalidated dictionary cache entry simply by resetting the
associated long-lived memory context. However, that does not work
for ispell affixes that make use of regular expressions, because
the regex library deals in plain old malloc. Hence, we leaked
compiled regex(es) any time we dropped such a cache entry. That
could quickly add up, since even a fairly trivial regex can use up
tens of kB, and a large one can eat megabytes. Add a memory context
callback to ensure that a regex gets freed when its owning cache
entry is cleared.
Found via valgrind testing.
This problem is ancient, so back-patch to all supported branches.
Discussion: https://postgr.es/m/3816764.1616104288@sss.pgh.pa.us
Some code paths in this function perform syscache lookups, which
can lead to table accesses and possibly leakage of cruft into
the caller's context. If said context is CacheMemoryContext,
we eventually will have visible bloat. But fixing this is no
harder than moving one memory context switch step. (The other
callers don't have a problem.)
Andres Freund and I independently found this via valgrind testing.
Back-patch to v12 where this code was added.
Discussion: https://postgr.es/m/20210317023101.anvejcfotwka6gaa@alap3.anarazel.de
Discussion: https://postgr.es/m/3816764.1616104288@sss.pgh.pa.us
Although these lists are usually NIL, and even when not empty
are unlikely to be large, constant relcache update traffic could
eventually result in visible bloat of CacheMemoryContext.
Found via valgrind testing.
Back-patch to v10 where this field was added.
Discussion: https://postgr.es/m/3816764.1616104288@sss.pgh.pa.us
pg_read_file() is the function that's in core, pg_file_read() is in
adminpack. But when using pg_file_read() in adminpack it calls the *C*
level function pg_read_file() in core, which probably threw the original
author off. But the error hint should be about the SQL function.
Reported-By: Sergei Kornilov
Backpatch-through: 11
Discussion: https://postgr.es/m/373021616060475@mail.yandex.ru
Robert Foggia of Trustwave reported that read_tablespace_map()
fails to prevent an overrun of its on-stack input buffer.
Since the tablespace map file is presumed trustworthy, this does
not seem like an interesting security vulnerability, but still
we should fix it just in the name of robustness.
While here, document that pg_basebackup's --tablespace-mapping option
doesn't work with tar-format output, because it doesn't. To make it
work, we'd have to modify the tablespace_map file within the tarball
sent by the server, which might be possible but I'm not volunteering.
(Less-painful solutions would require changing the basebackup protocol
so that the source server could adjust the map. That's not very
appetizing either.)
With very unlucky timing and parallel_leader_participation off, PHJ
could attempt to access per-batch state just as it was being freed.
There was code intended to prevent that by checking for a cleared
pointer, but it was buggy.
Fix, by introducing an extra barrier phase. The new phase
PHJ_BUILD_RUNNING means that it's safe to access the per-batch state to
find a batch to help with, and PHJ_BUILD_DONE means that it is too late.
The last to detach will free the array of per-batch state as before, but
now it will also atomically advance the phase at the same time, so that
late attachers can avoid the hazard, without the data race. This
mirrors the way per-batch hash tables are freed (see phases
PHJ_BATCH_PROBING and PHJ_BATCH_DONE).
Revealed by a one-off build farm failure, where BarrierAttach() failed a
sanity check assertion, because the memory had been clobbered by
dsa_free().
Back-patch to 11, where the code arrived.
Reported-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/20200929061142.GA29096%40paquier.xyz
After reading the root cert list from the ssl_ca_file, immediately
install it as client CA list of the new SSL context. That gives the
SSL context ownership of the list, so that SSL_CTX_free will free it.
This avoids a permanent memory leak if we fail further down in
be_tls_init(), which could happen if bogus CRL data is offered.
The leak could only amount to something if the CRL parameters get
broken after server start (else we'd just quit) and then the server
is SIGHUP'd many times without fixing the CRL data. That's rather
unlikely perhaps, but it seems worth fixing, if only because the
code is clearer this way.
While we're here, add some comments about the memory management
aspects of this logic.
Noted by Jelte Fennema and independently by Andres Freund.
Back-patch to v10; before commit de41869b6 it doesn't matter,
since we'd not re-execute this code during SIGHUP.
Discussion: https://postgr.es/m/16160-18367e56e9a28264@postgresql.org
psql's editing commands decide whether the user has edited the file
by checking for change of modification timestamp. This is probably
fine for a pre-existing file, but with a temporary file that is
created within the command, it's possible for a fast typist to
save-and-exit in less than the one-second granularity of stat(2)
timestamps. On Windows FAT filesystems the granularity is even
worse, 2 seconds, making the race a bit easier to hit.
To fix, try to set the temp file's mod time to be two seconds ago.
It's unlikely this would fail, but then again the race condition
itself is unlikely, so just ignore any error.
Also, we might as well check the file size as well as its mod time.
While this is a difficult bug to hit, it still seems worth
back-patching, to ensure that users' edits aren't lost.
Laurenz Albe, per gripe from Jacob Champion; based on fix suggestions
from Jacob and myself
Discussion: https://postgr.es/m/0ba3f2a658bac6546d9934ab6ba63a805d46a49b.camel@cybertec.at
GENERATED ALWAYS AS IDENTITY implies NOT NULL, but the code failed
to complain if you overrode that with "GENERATED ALWAYS AS IDENTITY
NULL". One might think the old behavior was a feature, but it was
inconsistent because the outcome varied depending on the order of
the clauses, so it seems to have been just an oversight.
Per bug #16913 from Pavel Boev. Back-patch to v10 where identity
columns were introduced.
Vik Fearing (minor tweaks by me)
Discussion: https://postgr.es/m/16913-3b5198410f67d8c6@postgresql.org
Revert two recent commits that had btree_index.sql drop regression test
indexes rather than leave them behind for pg_dump testing.
This is intended to restore pg_upgrade coverage of indexes with the
vacuum_cleanup_index_scale_factor storage parameter set on buildfarm
member crake.
Backpatch: 11-12 only
Commit 92785dac2 copied some logic related to advancement of inStart
from pqParseInput3 into getRowDescriptions and getAnotherTuple,
because it wanted to allow user-defined row processor callbacks to
potentially longjmp out of the library, and inStart would have to be
updated before that happened to avoid an infinite loop. We later
decided that that API was impossibly fragile and reverted it, but
we didn't undo all of the related code changes, and this bit of
messiness survived. Undo it now so that there's just one place in
pqParseInput3's processing where inStart is advanced; this will
simplify addition of better tracing support.
getParamDescriptions had grown similar processing somewhere along
the way (not in 92785dac2; I didn't track down just when), but it's
actually buggy because its handling of corrupt-message cases seems to
have been copied from the v2 logic where we lacked a known message
length. The cases where we "goto not_enough_data" should not simply
return EOF, because then we won't consume the message, potentially
creating an infinite loop. That situation now represents a
definitively corrupt message, and we should report it as such.
Although no field reports of getParamDescriptions getting stuck in
a loop have been seen, it seems appropriate to back-patch that fix.
I chose to back-patch all of this to keep the logic looking more alike
in supported branches.
Discussion: https://postgr.es/m/2217283.1615411989@sss.pgh.pa.us
The vacuum_cleanup_index_scale_factor storage parameter was set in a
btree index that was previously left behind in the regression test
database. As a result, the index gets tested within pg_dump and
pg_restore tests, as well as pg_upgrade testing. This won't work when
upgrading to Postgres 14, though, because the storage parameter was
removed on that version by commit 9f3665fb.
Fix the test failure by dropping the index in question.
Per buildfarm member crake.
Discussion: https://postgr.es/m/CAH2-WzmeXYBWdhF7BMhNjhq9exsk=E1ohqBFAwzPdXJZ1XDMUA@mail.gmail.com
Backpatch: 11-12 only
"SELECT pg_import_system_collations(0)" caused an assertion failure.
With a random nonzero argument --- or indeed with zero, in non-assert
builds --- it would happily make pg_collation entries with garbage
values of collnamespace. These are harmless as far as I can tell
(unless maybe the OID happens to become used for a schema, later on?).
In any case this isn't a security issue, since the function is
superuser-only. But it seems like a gotcha for unwary DBAs, so let's
add a check that the given OID belongs to some schema.
Back-patch to v10 where this function was introduced.
On Windows, CMD.EXE allegedly does not run a command that uses forward slashes,
so let's convert the path to use backslashes instead.
Backpatch to 10.
Author: Nitin Jadhav <nitinjadhavpostgres@gmail.com>
Reviewed-by: Juan José Santamaría Flecha <juanjo.santamaria@gmail.com>
Discussion: https://postgr.es/m/CAMm1aWaNDuaPYFYMAqDeJrZmPtNvLcJRS++CcZWY8LT6KcoBZw@mail.gmail.com
The same test for REINDEX (VERBOSE) was done twice, while it is clear
that the second test should use --concurrently. Issue introduced in
5dc92b8, for what looks like a copy-paste mistake.
Reviewed-by: Mark Dilger
Discussion: https://postgr.es/m/A7AE97EA-F4B0-4CAB-8FFF-3FECD31F9D63@enterprisedb.com
Backpatch-through: 12
AfterTriggerSaveEvent() wrongly allocates the slot in execution-span
memory context, whereas the correct thing is to allocate it in
a transaction-span context, because that's where the enclosing
AfterTriggersTableData instance belongs into.
Backpatch to 12 (the test back to 11, where it works well with no code
changes, and it's good to have to confirm that the case was previously
well supported); this bug seems introduced by commit ff11e7f4b9.
Reported-by: Bertrand Drouvot <bdrouvot@amazon.com>
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/39a71864-b120-5a5c-8cc5-c632b6f16761@amazon.com
Commit 866e24d47d added an assert that HEAP_XMAX_LOCK_ONLY and
HEAP_KEYS_UPDATED cannot appear together, on the faulty assumption that
the latter necessarily referred to an update and not a tuple lock; but
that's wrong, because SELECT FOR UPDATE can use precisely that
combination, as evidenced by the amcheck test case added here.
Remove the Assert(), and also patch amcheck's verify_heapam.c to not
complain if the combination is found. Also, out of overabundance of
caution, update (across all branches) README.tuplock to be more explicit
about this.
Author: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Mahendra Singh Thalor <mahi6run@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Discussion: https://postgr.es/m/20210124061758.GA11756@nol
When ON_ERROR_ROLLBACK is enabled, psql releases a temporary savepoint
if it's idle in a valid transaction block after executing a query. But psql
doesn't do that after RELEASE or ROLLBACK is executed because a temporary
savepoint has already been destroyed in that case.
This commit changes psql's ON_ERROR_ROLLBACK so that it doesn't release
a temporary savepoint also when COMMIT AND CHAIN is executed. A temporary
savepoint doesn't need to be released in that case because
COMMIT AND CHAIN also destroys any savepoints defined within the transaction
to commit. Otherwise psql tries to release the savepoint that
COMMIT AND CHAIN has already destroyed and cause an error
"ERROR: savepoint "pg_psql_temporary_savepoint" does not exist".
Back-patch to v12 where transaction chaining was added.
Reported-by: Arthur Nascimento
Author: Arthur Nascimento
Reviewed-by: Fujii Masao, Vik Fearing
Discussion: https://postgr.es/m/16867-3475744069228158@postgresql.org
This commit fixes COMMIT AND CHAIN command so that it starts new transaction
immediately even if savepoints are defined within the transaction to commit.
Previously COMMIT AND CHAIN command did not in that case because
commit 280a408b48 forgot to make CommitTransactionCommand() handle
a transaction chaining when the transaction state was TBLOCK_SUBCOMMIT.
Also this commit adds the regression test for COMMIT AND CHAIN command
when savepoints are defined.
Back-patch to v12 where transaction chaining was added.
Reported-by: Arthur Nascimento
Author: Fujii Masao
Reviewed-by: Arthur Nascimento, Vik Fearing
Discussion: https://postgr.es/m/16867-3475744069228158@postgresql.org
While poking at the regex code, I happened to notice that the bug
squashed in commit afcc8772e had a sibling: next() failed to return
a specific value associated with the '}' token for a "\{m,n\}"
quantifier when parsing in basic RE mode. Again, this could result
in treating the quantifier as non-greedy, which it never should be in
basic mode. For that to happen, the last character before "\}" that
sets "nextvalue" would have to set it to zero, or it'd have to have
accidentally been zero from the start. The failure can be provoked
repeatably with, for example, a bound ending in digit "0".
Like the previous patch, back-patch all the way.
If ExecGetInsertedCols(), ExecGetUpdatedCols() or ExecGetExtraUpdatedCols()
were called with a ResultRelInfo that's not in the range table and isn't a
partition routing target, the functions would dereference a NULL pointer,
relinfo->ri_RootResultRelInfo. Such ResultRelInfos are created when firing
RI triggers in tables that are not modified directly. None of the current
callers of these functions pass such relations, so this isn't a live bug,
but let's make them more robust.
Also update comment in ResultRelInfo; after commit 6214e2b228,
ri_RangeTableIndex is zero for ResultRelInfos created for partition tuple
routing.
Noted by Coverity. Backpatch down to v11, like commit 6214e2b228.
Reviewed-by: Tom Lane, Amit Langote
FreeBSD 13 gained O_DSYNC, which would normally cause wal_sync_method to
choose open_datasync as its default value. That may not be a good
choice for all systems, and performs worse than fdatasync in some
scenarios. Let's preserve the existing default behavior for now.
Like commit 576477e73c, which did the same for Linux, back-patch to all
supported releases.
Discussion: https://postgr.es/m/CA%2BhUKGLsAMXBQrCxCXoW-JsUYmdOL8ALYvaX%3DCrHqWxm-nWbGA%40mail.gmail.com
While cleaning up after a parallel query or parallel index creation that
created temporary files, we could be interrupted by a statement timeout.
The error handling path would then fail to clean up the files when it
ran dsm_detach() again, because the callback was already popped off the
list. Prevent this hazard by holding interrupts while the cleanup code
runs.
Thanks to Heikki Linnakangas for this suggestion, and also to Kyotaro
Horiguchi, Masahiko Sawada, Justin Pryzby and Tom Lane for discussion of
this and earlier ideas on how to fix the problem.
Back-patch to all supported releases.
Reported-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/20191212180506.GR2082@telsasoft.com
Modern gcc and clang compilers offer alignment sanitizers, which help to detect
pointer misalignment. However, our codebase already contains x86-specific
crc32 computation code, which uses unalignment access. Thankfully, those
compilers also support the attribute, which disables alignment sanitizers at
the function level. This commit adds pg_attribute_no_sanitize_alignment(),
which wraps this attribute, and applies it to pg_comp_crc32c_sse42() function.
Back-patch of commits 993bdb9f9 and ad2ad698a, to enable doing
alignment testing in all supported branches.
Discussion: https://postgr.es/m/CAPpHfdsne3%3DT%3DfMNU45PtxdhSL_J2PjLTeS8rwKnJzUR4YNd4w%40mail.gmail.com
Discussion: https://postgr.es/m/475514.1612745257%40sss.pgh.pa.us
Author: Alexander Korotkov, revised by Tom Lane
Reviewed-by: Tom Lane
Given a regex pattern with a very long fixed prefix (approaching 500
characters), the result of pow(FIXED_CHAR_SEL, fixed_prefix_len) can
underflow to zero. Typically the preceding selectivity calculation
would have underflowed as well, so that we compute 0/0 and get NaN.
In released branches this leads to an assertion failure later on.
That doesn't happen in HEAD, for reasons I've not explored yet,
but it's surely still a bug.
To fix, just skip the division when the pow() result is zero, so
that we'll (most likely) return a zero selectivity estimate. In
the edge cases where "sel" didn't yet underflow, perhaps this
isn't desirable, but I'm not sure that the case is worth spending
a lot of effort on. The results of regex_selectivity_sub() are
barely worth the electrons they're written on anyway :-(
Per report from Alexander Lakhin. Back-patch to all supported versions.
Discussion: https://postgr.es/m/6de0a0c3-ada9-cd0c-3e4e-2fa9964b41e3@gmail.com
For an index, attstattarget can be updated using ALTER INDEX SET
STATISTICS. This data was lost on the new index after REINDEX
CONCURRENTLY.
The update of this field is done when the old and new indexes are
swapped to make the fix back-patchable. Another approach we could look
after in the long-term is to change index_create() to pass the wanted
values of attstattarget when creating the new relation, but, as this
would cause an ABI breakage this can be done only on HEAD.
Reported-by: Ronan Dunklau
Author: Michael Paquier
Reviewed-by: Ronan Dunklau, Tomas Vondra
Discussion: https://postgr.es/m/16628084.uLZWGnKmhe@laptop-ronand
Backpatch-through: 12
If a cross-partition UPDATE violates a constraint on the target partition,
and the columns in the new partition are in different physical order than
in the parent, the error message can reveal columns that the user does not
have SELECT permission on. A similar bug was fixed earlier in commit
804b6b6db4.
The cause of the bug is that the callers of the
ExecBuildSlotValueDescription() function got confused when constructing
the list of modified columns. If the tuple was routed from a parent, we
converted the tuple to the parent's format, but the list of modified
columns was grabbed directly from the child's RTE entry.
ExecUpdateLockMode() had a similar issue. That lead to confusion on which
columns are key columns, leading to wrong tuple lock being taken on tables
referenced by foreign keys, when a row is updated with INSERT ON CONFLICT
UPDATE. A new isolation test is added for that corner case.
With this patch, the ri_RangeTableIndex field is no longer set for
partitions that don't have an entry in the range table. Previously, it was
set to the RTE entry of the parent relation, but that was confusing.
NOTE: This modifies the ResultRelInfo struct, replacing the
ri_PartitionRoot field with ri_RootResultRelInfo. That's a bit risky to
backpatch, because it breaks any extensions accessing the field. The
change that ri_RangeTableIndex is not set for partitions could potentially
break extensions, too. The ResultRelInfos are visible to FDWs at least,
and this patch required small changes to postgres_fdw. Nevertheless, this
seem like the least bad option. I don't think these fields widely used in
extensions; I don't think there are FDWs out there that uses the FDW
"direct update" API, other than postgres_fdw. If there is, you will get a
compilation error, so hopefully it is caught quickly.
Backpatch to 11, where support for both cross-partition UPDATEs, and unique
indexes on partitioned tables, were added.
Reviewed-by: Amit Langote
Security: CVE-2021-3393
rewriteRuleAction() neglected this step, although it was careful to
propagate other similar flags such as hasSubLinks or hasRowSecurity.
Omitting to transfer hasRecursive is just cosmetic at the moment,
but omitting hasModifyingCTE is a live bug, since the executor
certainly looks at that.
The proposed test case only fails back to v10, but since the executor
examines hasModifyingCTE in 9.x as well, I suspect that a test case
could be devised that fails in older branches. Given the nearness
of the release deadline, though, I'm not going to spend time looking
for a better test.
Report and patch by Greg Nancarrow, cosmetic changes by me
Discussion: https://postgr.es/m/CAJcOf-fAdj=nDKMsRhQzndm-O13NY4dL6xGcEvdX5Xvbbi0V7g@mail.gmail.com
Generally, members of inheritance trees must be plain tables (or,
in more recent versions, foreign tables). ALTER TABLE INHERIT
rejects creating an inheritance relationship that has a view at
either end. When DefineQueryRewrite attempts to convert a relation
to a view, it already had checks prohibiting doing so for partitioning
parents or children as well as traditional-inheritance parents ...
but it neglected to check that a traditional-inheritance child wasn't
being converted. Since the planner assumes that any inheritance
child is a table, this led to making plans that tried to do a physical
scan on a view, causing failures (or even crashes, in recent versions).
One could imagine trying to support such a case by expanding the view
normally, but since the rewriter runs before the planner does
inheritance expansion, it would take some very fundamental refactoring
to make that possible. There are probably a lot of other parts of the
system that don't cope well with such a situation, too. For now,
just forbid it.
Per bug #16856 from Yang Lin. Back-patch to all supported branches.
(In versions before v10, this includes back-patching the portion of
commit 501ed02cf that added has_superclass(). Perhaps the lack of
that infrastructure partially explains the missing check.)
Discussion: https://postgr.es/m/16856-0363e05c6e1612fd@postgresql.org
If a multi-byte character is escaped with a backslash in TEXT mode input,
and the encoding is one of the client-only encodings where the bytes after
the first one can have an ASCII byte "embedded" in the char, we didn't
skip the character correctly. After a backslash, we only skipped the first
byte of the next character, so if it was a multi-byte character, we would
try to process its second byte as if it was a separate character. If it
was one of the characters with special meaning, like '\n', '\r', or
another '\\', that would cause trouble.
One such exmple is the byte sequence '\x5ca45c2e666f6f' in Big5 encoding.
That's supposed to be [backslash][two-byte character][.][f][o][o], but
because the second byte of the two-byte character is 0x5c, we incorrectly
treat it as another backslash. And because the next character is a dot, we
parse it as end-of-copy marker, and throw an "end-of-copy marker corrupt"
error.
Backpatch to all supported versions.
Reviewed-by: John Naylor, Kyotaro Horiguchi
Discussion: https://www.postgresql.org/message-id/a897f84f-8dca-8798-3139-07da5bb38728%40iki.fi
If a portal is used to run a prepared CALL or DO statement that
contains a ROLLBACK, PortalRunMulti fails because the portal's
statement list gets cleared by the rollback. (Since the grammar
doesn't allow CALL/DO in PREPARE, the only easy way to get to this is
via extended query protocol, which treats all inputs as prepared
statements.) It's difficult to avoid resetting the portal early
because of resource-management issues, so work around this by teaching
PortalRunMulti to be wary of portal->stmts having suddenly become NIL.
The crash has only been seen to occur in v13 and HEAD (as a
consequence of commit 1cff1b95a having added an extra touch of
portal->stmts). But even before that, the code involved touching a
List that the portal no longer has any claim on. In the test case at
hand, the List will still exist because of another refcount on the
cached plan; but I'm far from convinced that it's impossible for the
cached plan to have been dropped by the time control gets back to
PortalRunMulti. Hence, backpatch to v11 where nested transactions
were added.
Thomas Munro and Tom Lane, per bug #16811 from James Inform
Discussion: https://postgr.es/m/16811-c1b599b2c6c2d622@postgresql.org
Generation expressions of generated columns are always inherited, so
there is no need to set them separately in child tables, and there is
no syntax to do so either. The code previously used the code paths
for the handling of default values, for which different rules apply;
in particular it might want to set a default value explicitly for an
inherited column. This resulted in unrestorable dumps. For generated
columns, just skip them in inherited tables.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/15830.1575468847%40sss.pgh.pa.us
In a cluster having used CREATE INDEX CONCURRENTLY while having enabled
prepared transactions, queries that use the resulting index can silently
fail to find rows. Fix this for future CREATE INDEX CONCURRENTLY by
making it wait for prepared transactions like it waits for ordinary
transactions. This expands the VirtualTransactionId structure domain to
admit prepared transactions. It may be necessary to reindex to recover
from past occurrences. Back-patch to 9.5 (all supported versions).
Andrey Borodin, reviewed (in earlier versions) by Tom Lane and Michael
Paquier.
Discussion: https://postgr.es/m/2E712143-97F7-4890-B470-4A35142ABC82@yandex-team.ru
Per buildfarm and local experimentation, bleeding-edge gcc isn't
convinced that the MemSet in reorder_function_arguments() is safe.
Shut it up by adding an explicit check that pronargs isn't negative,
and by changing MemSet to memset. (It appears that either change is
enough to quiet the warning at -O2, but let's do both to be sure.)
perform_pruning_combine_step() was not taught about the number of
partition indexes used in hash partitioning; more embarrassingly,
get_matching_hash_bounds() also had it wrong. These errors are masked
in the common case where all the partitions have the same modulus
and no partition is missing. However, with missing or unequal-size
partitions, we could erroneously prune some partitions that need
to be scanned, leading to silently wrong query answers.
While a minimal-footprint fix for this could be to export
get_partition_bound_num_indexes and make the incorrect functions use it,
I'm of the opinion that that function should never have existed in the
first place. It's not reasonable data structure design that
PartitionBoundInfoData lacks any explicit record of the length of
its indexes[] array. Perhaps that was all right when it could always
be assumed equal to ndatums, but something should have been done about
it as soon as that stopped being true. Putting in an explicit
"nindexes" field makes both partition_bounds_equal() and
partition_bounds_copy() simpler, safer, and faster than before,
and removes explicit knowledge of the number-of-partition-indexes
rules from some other places too.
This change also makes get_hash_partition_greatest_modulus obsolete.
I left that in place in case any external code uses it, but no core
code does anymore.
Per bug #16840 from Michał Albrycht. Back-patch to v11 where the
hash partitioning code came in. (In the back branches, add the new
field at the end of PartitionBoundInfoData to minimize ABI risks.)
Discussion: https://postgr.es/m/16840-571a22976f829ad4@postgresql.org
We had "short *mdy" in the extern declarations, but "short mdy[3]"
in the actual function definitions. Per C99 these are equivalent,
but recent versions of gcc have started to issue warnings about
the inconsistency. Clean it up before the warnings get any more
widespread.
Back-patch, in case anyone wants to build older PG versions with
bleeding-edge compilers.
Discussion: https://postgr.es/m/2401575.1611764534@sss.pgh.pa.us
doConnect() never returns connections in state CONNECTION_BAD, so
checking for that is pointless. Remove the code that does.
This code has been dead since ba708ea3dc, 20 years ago.
Discussion: https://postgr.es/m/20210126195224.GA20361@alvherre.pgsql
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
When building aggregate expression steps, strict checks need a bailout
jump for when a null value is encountered, so there is a list of steps
that require later adjustment. Adding entries to that list for steps
that aren't actually strict would be harmless, except that there is an
Assert which catches them. This leads to spurious errors on asserts
builds, for data sets that trigger parallel aggregation of an
aggregate with a non-strict deserialization function (no such
aggregates exist in the core system).
Repair by not adding the adjustment entry when it's not needed.
Backpatch back to 11 where the code was introduced.
Per a report from Darafei (Komzpa) of the PostGIS project; analysis
and patch by me.
Discussion: https://postgr.es/m/87mty7peb3.fsf@news-spur.riddles.org.uk
When reporting connection errors, we might show a database name in the
message that's not the one we actually tried to connect to, if the
database was taken from libpq defaults instead of from user parameters.
Fix such error messages to use PQdb(), which reports the correct name.
(But, per commit 2930c05634, make sure not to try to print NULL.)
Apply to branches 9.5 through 13. Branch master has already been
changed differently by commit 58cd8dca3d.
Reported-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CA+TgmobssJ6rS22dspWnu-oDxXevGmhMD8VcRBjmj-b9UDqRjw@mail.gmail.com
The loops to identify word boundaries could access past the end of
the input string. Likely that would never result in an actual
crash, but it makes valgrind unhappy.
The logic to try different numbers of words didn't work when the
input has two words but we only have a match to the first, eg
"\h with select". (We must "continue" the pass loop, not "break".)
The logic to compute nl_count was bizarrely managed, and in at
least two code paths could end up calling PageOutput with
nl_count = 0, resulting in failing to paginate output that should
have been fed to the pager. Also, in v12 and up, the nl_count
calculation hadn't been updated to account for the addition of a URL.
The PQExpBuffer holding the command syntax details wasn't freed,
resulting in a session-lifespan memory leak.
While here, improve some comments, choose a more descriptive name
for a variable, fix inconsistent datatype choice for another variable.
Per bug #16837 from Alexander Lakhin. This code is very old,
so back-patch to all supported branches.
Kyotaro Horiguchi and Tom Lane
Discussion: https://postgr.es/m/16837-479bcd56040c71b3@postgresql.org