It's hard to disable ASLR on current macOS releases, for testing with
-DEXEC_BACKEND. You could already set the environment variable
PG_SHMEM_ADDR to something not likely to collide with mappings created
earlier in process startup. Let's also provide a default value that
works on current releases and architectures, for developer convenience.
As noted in the pre-existing comment, this is a horrible hack, but
-DEXEC_BACKEND is only used by Unix-based PostgreSQL developers for
testing some otherwise Windows-only code paths, so it seems excusable.
Back-patch to all supported branches.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20210806032944.m4tz7j2w47mant26%40alap3.anarazel.de
Rather than trying to pick table aliases that won't conflict with
any possible user-defined matview column name, adjust the queries'
syntax so that the aliases are only used in places where they can't be
mistaken for column names. Mostly this consists of writing "alias.*"
not just "alias", which adds clarity for humans as well as machines.
We do have the issue that "SELECT alias.*" acts differently from
"SELECT alias", but we can use the same hack ruleutils.c uses for
whole-row variables in SELECT lists: write "alias.*::compositetype".
We might as well revert to the original aliases after doing this;
they're a bit easier to read.
Like 75d66d10e, back-patch to all supported branches.
Discussion: https://postgr.es/m/2488325.1628261320@sss.pgh.pa.us
Formerly, the numeric code tested whether an integer value of a larger
type would fit in a smaller type by casting it to the smaller type and
then testing if the reverse conversion produced the original value.
That's perfectly fine, except that it caused a test failure on
buildfarm animal castoroides, most likely due to a compiler bug.
Instead, do these tests by comparing against PG_INT16/32_MIN/MAX. That
matches existing code in other places, such as int84(), which is more
widely tested, and so is less likely to go wrong.
While at it, add regression tests covering the numeric-to-int8/4/2
conversions, and adjust the recently added tests to the style of
434ddfb79a (on the v11 branch) to make failures easier to diagnose.
Per buildfarm via Tom Lane, reviewed by Tom Lane.
Discussion: https://postgr.es/m/2394813.1628179479%40sss.pgh.pa.us
This fixes a long-standing bug when using to_char() to format a
numeric value in scientific notation -- if the value's exponent is
less than -NUMERIC_MAX_DISPLAY_SCALE-1 (-1001), it produced a
division-by-zero error.
The reason for this error was that get_str_from_var_sci() divides its
input by 10^exp, which it produced using power_var_int(). However, the
underflow test in power_var_int() causes it to return zero if the
result scale is too small. That's not a problem for power_var_int()'s
only other caller, power_var(), since that limits the rscale to 1000,
but in get_str_from_var_sci() the exponent can be much smaller,
requiring a much larger rscale. Fix by introducing a new function to
compute 10^exp directly, with no rscale limit. This also allows 10^exp
to be computed more efficiently, without any numeric multiplication,
division or rounding.
Discussion: https://postgr.es/m/CAEZATCWhojfH4whaqgUKBe8D5jNHB8ytzemL-PnRx+KCTyMXmg@mail.gmail.com
This fixes a couple of related problems that arise when raising
numbers to very large powers.
Firstly, when raising a negative number to a very large integer power,
the result should be well-defined, but the previous code would only
cope if the exponent was small enough to go through power_var_int().
Otherwise it would throw an internal error, attempting to take the
logarithm of a negative number. Fix this by adding suitable handling
to the general case in power_var() to cope with negative bases,
checking for integer powers there.
Next, when raising a (positive or negative) number whose absolute
value is slightly less than 1 to a very large power, the result should
approach zero as the power is increased. However, in some cases, for
sufficiently large powers, this would lose all precision and return 1
instead of 0. This was due to the way that the local_rscale was being
calculated for the final full-precision calculation:
local_rscale = rscale + (int) val - ln_dweight + 8
The first two terms on the right hand side are meant to give the
number of significant digits required in the result ("val" being the
estimated result weight). However, this failed to account for the fact
that rscale is clipped to a maximum of NUMERIC_MAX_DISPLAY_SCALE
(1000), and the result weight might be less then -1000, causing their
sum to be negative, leading to a loss of precision. Fix this by
forcing the number of significant digits calculated to be nonnegative.
It's OK for it to be zero (when the result weight is less than -1000),
since the local_rscale value then includes a few extra digits to
ensure an accurate result.
Finally, add additional underflow checks to exp_var() and power_var(),
so that they consistently return zero for cases like this where the
result is indistinguishable from zero. Some paths through this code
already returned zero in such cases, but others were throwing overflow
errors.
Dean Rasheed, reviewed by Yugo Nagata.
Discussion: http://postgr.es/m/CAEZATCW6Dvq7+3wN3tt5jLj-FyOcUgT5xNoOqce5=6Su0bCR0w@mail.gmail.com
If a file is truncated, we must update minRecoveryPoint. Once a file is
truncated, there's no going back; it would not be safe to stop recovery
at a point earlier than that anymore.
Commit 7bffc9b7bf changed xact_redo_commit() so that it updates
minRecoveryPoint on truncation, but forgot to change xact_redo_abort().
Back-patch to all supported versions.
Reported-by: mengjuan.cmj@alibaba-inc.com
Author: Fujii Masao
Reviewed-by: Heikki Linnakangas
Discussion: https://postgr.es/m/b029fce3-4fac-4265-968e-16f36ff4d075.mengjuan.cmj@alibaba-inc.com
This changes the behavior of examining the pg_file_settings view after
changing a config option that requires restart. The user needs to know
that any change of such options does not take effect until a restart,
and this worked correctly if the line is edited without removing it.
However, for the case where the line is removed altogether, the flag
doesn't get set, because a flag was only set in set_config_option, but
that's not called for lines removed. Repair.
(Ref.: commits 62d16c7fc5 and a486e35706)
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/202107262302.xsfdfc5sb7sh@alvherre.pgsql
The error messages using the word "non-negative" are confusing
because it's ambiguous about whether it accepts zero or not.
This commit improves those error messages by replacing it with
less ambiguous word like "greater than zero" or
"greater than or equal to zero".
Also this commit added the note about the word "non-negative" to
the error message style guide, to help writing the new error messages.
When postgres_fdw option fetch_size was set to zero, previously
the error message "fetch_size requires a non-negative integer value"
was reported. This error message was outright buggy. Therefore
back-patch to all supported versions where such buggy error message
could be thrown.
Reported-by: Hou Zhijie
Author: Bharath Rupireddy
Reviewed-by: Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/OS0PR01MB5716415335A06B489F1B3A8194569@OS0PR01MB5716.jpnprd01.prod.outlook.com
Add pg_resetxlog -u option to set the oldest xid in pg_control.
Previously -x set this value be -2 billion less than the -x value.
However, this causes the server to immediately scan all relation's
relfrozenxid so it can advance pg_control's oldest xid to be inside the
autovacuum_freeze_max_age range, which is inefficient and might disrupt
diagnostic recovery. pg_upgrade will use this option to better create
the new cluster to match the old cluster.
Reported-by: Jason Harvey, Floris Van Nee
Discussion: https://postgr.es/m/20190615183759.GB239428@rfd.leadboat.com, 87da83168c644fd9aae38f546cc70295@opammb0562.comp.optiver.com
Author: Bertrand Drouvot
Backpatch-through: 9.6
These have been introduced by 7fbe0c8, and could happen for
pg_basebackup and pg_receivewal.
Per report from Coverity for the ones in walmethods.c, I have spotted
the ones in receivelog.c after more review.
Backpatch-through: 10
This commit changes the startup process in the standby server so that
it handles the interrupt signals after waiting for wal_retrieve_retry_interval
on the latch and resetting it, before entering another wait on the latch.
This change causes the standby server to promptly handle interrupt signals.
Otherwise, previously, there was the case where the standby needs to
wait extra five seconds to shutdown when the shutdown request arrived
while the startup process was waiting for wal_retrieve_retry_interval
on the latch.
Author: Fujii Masao, but implementation idea is from Soumyadeep Chakraborty
Reviewed-by: Soumyadeep Chakraborty
Discussion: https://postgr.es/m/9d7e6ab0-8a53-ddb9-63cd-289bcb25fe0e@oss.nttdata.com
Per discussion of BUG #17073, back-patch to all supported versions.
Discussion: https://postgr.es/m/17073-1a5fdaed0fa5d4d0@postgresql.org
We have an implementation restriction that PREPARE TRANSACTION can't
handle cases where both session-lifespan and transaction-lifespan locks
are held on the same lockable object. (That's because we'd otherwise
need to acquire a new PROCLOCK entry during post-prepare cleanup, which
is an operation that might fail. The situation can only arise with odd
usages of advisory locks, so removing the restriction is probably not
worth the amount of effort it would take.) AtPrepare_Locks attempted
to enforce this, but its logic was many bricks shy of a load, because
it only detected cases where the session and transaction locks had the
same lockmode. Locks of different modes on the same object would lead
to the rather unhelpful message "PANIC: we seem to have dropped a bit
somewhere".
To fix, build a transient hashtable with one entry per locktag,
not one per locktag + mode, and use that to detect conflicts.
Per bug #17122 from Alexander Pyhalov. This bug is ancient,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/17122-04f3c32098a62233@postgresql.org
We previously took a hard-line attitude that callers should never print
a null string pointer, and doing so is worthy of an assertion failure
or crash. However, we've long since flushed out any easy-to-find bugs
of that nature. What remains is a lot of code that perhaps could fail
that way in hard-to-reach corner cases. For example, in something as
simple as
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("constraint \"%s\" for table \"%s\" does not exist",
conname, get_rel_name(relid))));
one must wonder whether it's completely guaranteed that get_rel_name
cannot return NULL in this context. If such a situation did occur,
the existing policy converts what might be a pretty minor bug into
a server crash condition. This is not good for robustness.
Hence, let's follow the lead of glibc and print "(null)" instead
of failing. We should, of course, still consider it a bug if that
behavior is reachable in ordinary use; but crashing seems less
desirable than not crashing.
This fix works across-the-board in v12 and up, where we always use
src/port/snprintf.c. Before that, on most platforms we're at the mercy
of the local libc, but it appears that Solaris 10 is the only supported
platform where we'd still get a crash. Most other platforms such as
*BSD, macOS, and Solaris 11 have adopted glibc's behavior at some
point. (AIX and HPUX just print "" not "(null)", but that's close
enough.) I've not checked what Windows' native printf would do, but
it doesn't matter because we've long used snprintf.c on that platform.
In v12 and up, also const-ify related code so that we're not casting
away const on the constant string. This is just neatnik-ism, since
next to no compilers will warn about that.
Discussion: https://postgr.es/m/17098-b960f3616c861f83@postgresql.org
If an error was raised during our initial attempt to check whether
a successfully-compiled expression is "simple", subsequent calls of
exec_stmt_execsql would suppose that stmt->mod_stmt was already computed
when it had not been. This could lead to assertion failures in debug
builds; in production builds the effect would typically be to act as
if INTO STRICT had been specified even when it had not been. Of course
that only matters if the subsequent attempt to execute the expression
succeeds, so that the problem can only be reached by fixing a failure
in some referenced, inline-able SQL function and then retrying the
calling plpgsql function in the same session.
(There might be even-more-obscure ways to change the expression's
behavior without changing the plpgsql function, but that one seems
like the only one people would be likely to hit in practice.)
The most foolproof way to fix this would be to arrange for
exec_prepare_plan to not set expr->plan until we've finished the
subsidiary simple-expression check. But it seems hard to do that
without creating reference-count leak issues. So settle for documenting
the hazard in a comment and fixing exec_stmt_execsql to test separately
for whether it's computed stmt->mod_stmt. (That adds a test-and-branch
per execution, but hopefully that's negligible in context.) In v11 and
up, also fix exec_stmt_call which had a variant of the same issue.
Per bug #17113 from Alexander Lakhin. Back-patch to all
supported branches.
Discussion: https://postgr.es/m/17113-077605ce00e0e7ec@postgresql.org
The logic handling the opening of new WAL segments was fuzzy when using
--compress if a partial, non-compressed, segment with the same base name
existed in the repository storing those files. In this case, using
--compress would cause the code to first check for the existence and the
size of a non-compressed segment, followed by the opening of a new
compressed, partial, segment. The code was accidentally working
correctly on most platforms as the buildfarm has proved, except
bowerbird where gzflush() could fail in this code path. It is wrong
anyway to take the code path used pre-padding when creating a new
partial, non-compressed, segment, so let's fix it.
Note that this issue exists when users mix successive runs of
pg_receivewal with or without compression, as discovered with the tests
introduced by ffc9dda.
While on it, this refactors the code so as code paths that need to know
about the ".gz" suffix are down from four to one in walmethods.c, easing
a bit the introduction of new compression methods. This addresses a
second issue where log messages generated for an unexpected failure
would not show the compressed segment name involved, which was
confusing, printing instead the name of the non-compressed equivalent.
Reported-by: Georgios Kokolatos
Discussion: https://postgr.es/m/YPDLz2x3o1aX2wRh@paquier.xyz
Backpatch-through: 10
We don't allow to create replication slot_name as an empty string ('') via
SQL API pg_create_logical_replication_slot() but it is allowed to be set
via Alter Subscription command. This will lead to apply worker repeatedly
keep trying to stream data via slot_name '' and the user is not allowed to
create the slot with that name.
Author: Japin Li
Reviewed-By: Ranier Vilela, Amit Kapila
Backpatch-through: 10, where it was introduced
Discussion: https://postgr.es/m/MEYP282MB1669CBD98E721C77CA696499B61A9@MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM
41469253e went to the trouble of removing a theoretical bug from
free_sort_tuple by checking if the tuple was NULL before freeing it. Let's
make this a little more robust by also setting the tuple to NULL so that
should we be called again we won't end up doing a pfree on the already
pfree'd tuple. Per advice from Tom Lane.
Discussion: https://postgr.es/m/3188192.1626136953@sss.pgh.pa.us
Backpatch-through: 9.6, same as 41469253e
This fixes a theoretical bug in tuplesort.c which, if a bounded sort was
used in combination with a byval Datum sort (tuplesort_begin_datum), when
switching the sort to a bounded heap in make_bounded_heap(), we'd call
free_sort_tuple(). The problem was that when sorting Datums of a byval
type, the tuple is NULL and free_sort_tuple() would free the memory for it
regardless of that. This would result in a crash.
Here we fix that simply by adding a check to see if the tuple is NULL
before trying to disassociate and free any memory belonging to it.
The reason this bug is only theoretical is that nowhere in the current
code base do we do tuplesort_set_bound() when performing a Datum sort.
However, let's backpatch a fix for this as if any extension uses the code
in this way then it's likely to cause problems.
Author: Ronan Dunklau
Discussion: https://postgr.es/m/CAApHDvpdoqNC5FjDb3KUTSMs5dg6f+XxH4Bg_dVcLi8UYAG3EQ@mail.gmail.com
Backpatch-through: 9.6, oldest supported version
This should have been removed in commit 7e30c186da, which split the loop
into two. Only the first loop uses the 'from' variable; updating it in
the second loop is bogus. It was never read after the first loop, so this
was harmless and surely optimized away by the compiler, but let's be tidy.
Backpatch to all supported versions.
Author: Ranier Vilela
Discussion: https://www.postgresql.org/message-id/CAEudQAoWq%2BAL3BnELHu7gms2GN07k-np6yLbukGaxJ1vY-zeiQ%40mail.gmail.com
Although we were careful to lock the object being added or dropped,
we failed to get any sort of lock on the extension itself. This
allowed the ALTER to proceed in parallel with a DROP EXTENSION,
which is problematic for a couple of reasons. If both commands
succeeded we'd be left with a dangling link in pg_depend, which
would cause problems later. Also, if the ALTER failed for some
reason, it might try to print the extension's name, and that could
result in a crash or (in older branches) a silly error message
complaining about extension "(null)".
Per bug #17098 from Alexander Lakhin. Back-patch to all
supported branches.
Discussion: https://postgr.es/m/17098-b960f3616c861f83@postgresql.org
This fixes an overflow error when using the numeric * operator if the
result has more than 16383 digits after the decimal point by rounding
the result. Overflow errors should only occur if the result has too
many digits *before* the decimal point.
Discussion: https://postgr.es/m/CAEZATCUmeFWCrq2dNzZpRj5+6LfN85jYiDoqm+ucSXhb9U2TbA@mail.gmail.com
The separate libldap_r is gone and libldap itself is now always
thread-safe. Unfortunately there seems no easy way to tell by
inspection whether libldap is thread-safe, so we have to take
it on faith that libldap is thread-safe if there's no libldap_r.
That should be okay, as it appears that libldap_r was a standard
part of the installation going back at least 20 years.
Report and patch by Adrian Ho. Back-patch to all supported
branches, since people might try to build any of them with
a newer OpenLDAP.
Discussion: https://postgr.es/m/17083-a19190d9591946a7@postgresql.org
Since the executor can't cope with a utility statement appearing
as a node of a plan tree, we can't support cases where a rewrite
rule inserts a NOTIFY into an INSERT/UPDATE/DELETE command appearing
in a WITH clause of a larger query. (One can imagine ways around
that, but it'd be a new feature not a bug fix, and so far there's
been no demand for it.) RewriteQuery checked for this, but it
missed the case where the DML command rewrites to *only* a NOTIFY.
That'd lead to crashes later on in planning. Add the missed check,
and improve the level of testing of this area.
Per bug #17094 from Yaoguang Chen. It's been busted since WITH
was introduced, so back-patch to all supported branches.
Discussion: https://postgr.es/m/17094-bf15dff55eaf2e28@postgresql.org
Due to how pg_size_pretty(bigint) was implemented, it's possible that when
given a negative number of bytes that the returning value would not match
the equivalent positive return value when given the equivalent positive
number of bytes. This was due to two separate issues.
1. The function used bit shifting to convert the number of bytes into
larger units. The rounding performed by bit shifting is not the same as
dividing. For example -3 >> 1 = -2, but -3 / 2 = -1. These two
operations are only equivalent with positive numbers.
2. The half_rounded() macro rounded towards positive infinity. This meant
that negative numbers rounded towards zero and positive numbers rounded
away from zero.
Here we fix#1 by dividing the values instead of bit shifting. We fix#2
by adjusting the half_rounded macro always to round away from zero.
Additionally, adjust the pg_size_pretty(numeric) function to be more
explicit that it's using division rather than bit shifting. A casual
observer might have believed bit shifting was used due to a static
function being named numeric_shift_right. However, that function was
calculating the divisor from the number of bits and performed division.
Here we make that more clear. This change is just cosmetic and does not
affect the return value of the numeric version of the function.
Here we also add a set of regression tests both versions of
pg_size_pretty() which test the values directly before and after the
function switches to the next unit.
This bug was introduced in 8a1fab36a. Prior to that negative values were
always displayed in bytes.
Author: Dean Rasheed, David Rowley
Discussion: https://postgr.es/m/CAEZATCXnNW4HsmZnxhfezR5FuiGgp+mkY4AzcL5eRGO4fuadWg@mail.gmail.com
Backpatch-through: 9.6, where the bug was introduced.
Commit 03ffc4d6d added logic to bypass all caching behavior in
LookupOpclassInfo when CLOBBER_CACHE_ALWAYS is enabled. It doesn't
look like I stopped to think much about what that would cost, but
recent investigation shows that the cost is enormous: it roughly
doubles the time needed for cache-clobber test runs.
There does seem to be value in this behavior when trying to test
the opclass-cache loading logic itself, but for other purposes the
cost is excessive. Hence, let's back off to doing this only when
debug_invalidate_system_caches_always is at least 3; or in older
branches, when CLOBBER_CACHE_RECURSIVELY is defined.
While here, clean up some other minor issues in LookupOpclassInfo.
Re-order the code so we aren't left with broken cache entries (leading
to later core dumps) in the unlikely case that we suffer OOM while
trying to allocate space for a new entry. (That seems to be my
oversight in 03ffc4d6d.) Also, in >= v13, stop allocating one array
entry too many. That's evidently left over from sloppy reversion in
851b14b0c.
Back-patch to all supported branches, mainly to reduce the runtime
of cache-clobbering buildfarm animals.
Discussion: https://postgr.es/m/1370856.1625428625@sss.pgh.pa.us
The existing code tried to do syscache lookups in an already-failed
transaction, which is problematic to say the least. After some
consideration of alternatives, the best fix seems to be to just drop
type names from the error message altogether. The table and column
names seem like sufficient localization. If the user is unsure what
types are involved, she can check the local and remote table
definitions.
Having done that, we can also discard the LogicalRepTypMap hash
table, which had no other use. Arguably, LOGICAL_REP_MSG_TYPE
replication messages are now obsolete as well; but we should
probably keep them in case some other use emerges. (The complexity
of removing something from the replication protocol would likely
outweigh any savings anyhow.)
Masahiko Sawada and Bharath Rupireddy, per complaint from Andres
Freund. Back-patch to v10 where this code originated.
Discussion: https://postgr.es/m/20210106020229.ne5xnuu6wlondjpe@alap3.anarazel.de
The prove_installcheck recipe in src/Makefile.global.in was emitting
bogus paths for a couple of elements when used with PGXS. Here we create
a separate recipe for the PGXS case that does it correctly. We also take
the opportunity to make the make the file more readable by breaking up
the prove_installcheck and prove_check recipes across several lines, and
to remove the setting for REGRESS_SHLIB to src/test/recovery/Makefile,
which is the only set of tests that actually need it.
Backpatch to all live branches
Discussion: https://postgr.es/m/f2401388-936b-f4ef-a07c-a0bcc49b3300@dunslane.net
ICU 69 causes compile failures with PostgreSQL 10. ICU 69 has
switched to using stdbool.h, which conflicts with the home-made
definitions that we used until PostgreSQL 10. Newer PostgreSQL major
versions are therefore not affected. (Older PostgreSQL versions don't
have ICU support.)
The workaround is to undefine "bool" after including ICU headers,
similar to the solution already in place for plperl for the same
underlying reasons.
Discussion: https://www.postgresql.org/message-id/flat/28588e5a-c204-0361-01f1-a1ee1b590233%40enterprisedb.com
Causing a core dump on out-of-memory seems pretty unfriendly,
and surely is far outside the expected behavior of a general-purpose
library. Just print an error message (as we did already) and return.
These functions unfortunately don't have an error return convention,
but code using them is probably just looking for a quick-n-dirty
print method and wouldn't bother to check anyway.
Although these functions are semi-deprecated, it still seems
appropriate to back-patch this. In passing, also back-patch
b90e6cef1, just to reduce cosmetic differences between the
branches.
Discussion: https://postgr.es/m/3122443.1624735363@sss.pgh.pa.us
83158f7 has improved index_set_state_flags() so as it is possible to use
transactional updates when updating pg_index state flags, but there was
not really a test case which stressed directly the possibility it fixed.
This commit adds such a test, using a predicate that looks valid in
appearance but calls a stable function.
Author: Andrey Lepikhov
Discussion: https://postgr.es/m/9b905019-5297-7372-0ad2-e1a4bb66a719@postgrespro.ru
Backpatch-through: 9.6
3c84046 is the original commit that introduced index_set_state_flags(),
where the presence of SnapshotNow made necessary the use of an in-place
update. SnapshotNow has been removed in 813fb03, so there is no actual
reasons to not make this operation transactional.
As reported by Andrey, it is possible to trigger the assertion of this
routine expecting no transactional updates when switching the pg_index
state flags, using a predicate mark as immutable but calling stable or
volatile functions. 83158f7 has been around for a couple of months on
HEAD now with no issues found related to it, so it looks safe enough for
a backpatch.
Reported-by: Andrey Lepikhov
Author: Michael Paquier
Reviewed-by: Anastasia Lubennikova
Discussion: https://postgr.es/m/20200903080440.GA8559@paquier.xyz
Discussion: https://postgr.es/m/9b905019-5297-7372-0ad2-e1a4bb66a719@postgrespro.ru
Backpatch-through: 9.6
specscanner.l leaked a kilobyte of memory per token of the spec file.
Apparently somebody thought that the introductory code block would be
executed once; but it's once per yylex() call.
A couple of functions in isolationtester.c leaked small amounts of
memory due to not bothering to free one-time allocations. Might
as well improve these so that valgrind gives this program a clean
bill of health. Also get rid of an ugly static variable.
Coverity complained about one of the one-time leaks, which led me
to try valgrind'ing isolationtester, which led to discovery of the
larger leak.
It's not really necessary for this function to open or lock the
relation associated with the pg_policy entry it's modifying. The
error checks it's making on the rel are if anything counterproductive
(e.g., if we don't want to allow installation of policies on system
catalogs, here is not the place to prevent that). In particular, it
seems just wrong to insist on an ownership check. That has the net
effect of forcing people to use superuser for DROP OWNED BY, which
surely is not an effect we want. Also there is no point in rebuilding
the dependencies of the policy expressions, which aren't being
changed. Lastly, locking the table also seems counterproductive; it's
not helping to prevent race conditions, since we failed to re-read the
pg_policy row after acquiring the lock. That means that concurrent
DDL would likely result in "tuple concurrently updated/deleted"
errors; which is the same behavior this code will produce, with less
overhead.
Per discussion of bug #17062. Back-patch to all supported versions,
as the failure cases this eliminates seem just as undesirable in 9.6
as in HEAD.
Discussion: https://postgr.es/m/1573181.1624220108@sss.pgh.pa.us
A walsender process that has executed a SQL command left the text of
that command in pg_stat_activity.query indefinitely, which is quite
confusing if it's in RUNNING state but not doing that query. An easy
and useful fix is to treat replication commands as if they were SQL
queries, and show them in pg_stat_activity according to the same rules
as for regular queries. While we're at it, it seems also sensible to
set debug_query_string, allowing error logging and debugging to see
the replication command.
While here, clean up assorted silliness in exec_replication_command:
* Clean up SQLCmd code path, and fix its only-accidentally-not-buggy
memory management.
* Remove useless duplicate call of SnapBuildClearExportedSnapshot().
* replication_scanner_finish() was never called.
Back-patch of commit f560209c6 into v10-v13. I'd originally felt
that this didn't merit back-patching, but subsequent confusion
while debugging walsender problems suggests that it'll be useful.
Also, the original commit has now aged long enough to provide some
comfort that it won't cause problems.
Discussion: https://postgr.es/m/2673480.1624557299@sss.pgh.pa.us
Discussion: https://postgr.es/m/880181.1600026471@sss.pgh.pa.us
Contrary to the comment here, POSIX does not guarantee atomicity of a
read(), if another process calls write() concurrently. Or at least Linux
does not. Add locking to load_relmap_file() to avoid the race condition.
Fixes bug #17064. Thanks to Alexander Lakhin for the report and test case.
Backpatch-through: 9.6, all supported versions.
Discussion: https://www.postgresql.org/message-id/17064-bb0d7904ef72add3@postgresql.org
For no obvious reason, isolationtester has always insisted that
session and step names be written with double quotes. This is
fairly tedious and does little for test readability, especially
since the names that people actually choose almost always look
like normal identifiers. Hence, let's tweak the lexer to allow
SQL-like identifiers not only double-quoted strings.
(They're SQL-like, not exactly SQL, because I didn't add any
case-folding logic. Also there's no provision for U&"..." names,
not that anyone's likely to care.)
There is one incompatibility introduced by this change: if you write
"foo""bar" with no space, that used to be taken as two identifiers,
but now it's just one identifier with an embedded quote mark.
I converted all the src/test/isolation/ specfiles to remove
unnecessary double quotes, but stopped there because my
eyes were glazing over already.
Like 741d7f104, back-patch to all supported branches, so that this
isn't a stumbling block for back-patching isolation test changes.
Discussion: https://postgr.es/m/759113.1623861959@sss.pgh.pa.us
Our uses of gss_display_status() and gss_display_name() assumed
that the gss_buffer_desc strings returned by those functions are
null-terminated. It appears that they generally are, given the
lack of field complaints up to now. However, the available
documentation does not promise this, and some man pages
for gss_display_status() show examples that rely on the
gss_buffer_desc.length field instead of expecting null
termination. Also, we now have a report that on some
implementations, clang's address sanitizer is of the opinion
that the byte after the specified length is undefined.
Hence, change the code to rely on the length field instead.
This might well be cosmetic rather than fixing any real bug, but
it's hard to be sure, so back-patch to all supported branches.
While here, also back-patch the v12 changes that made pg_GSS_error
deal honestly with multiple messages available from
gss_display_status.
Per report from Sudheer H R.
Discussion: https://postgr.es/m/5372B6D4-8276-42C0-B8FB-BD0918826FC3@tekenlight.com
Previously, isolationtester displayed SQL query results using some
ad-hoc code that clearly hadn't had much effort expended on it.
Field values longer than 14 characters weren't separated from
the next field, and usually caused misalignment of the columns
too. Also there was no visual separation of a query's result
from subsequent isolationtester output. This made test result
files confusing and hard to read.
To improve matters, let's use libpq's PQprint() function. Although
that's long since unused by psql, it's still plenty good enough
for the purpose here.
Like 741d7f104, back-patch to all supported branches, so that this
isn't a stumbling block for back-patching isolation test changes.
Discussion: https://postgr.es/m/582362.1623798221@sss.pgh.pa.us
We've long contended with isolation test results that aren't entirely
stable. Some test scripts insert long delays to try to force stable
results, which is not terribly desirable; but other erratic failure
modes remain, causing unrepeatable buildfarm failures. I've spent a
fair amount of time trying to solve this by improving the server-side
support code, without much success: that way is fundamentally unable
to cope with diffs that stem from chance ordering of arrival of
messages from different server processes.
We can improve matters on the client side, however, by annotating
the test scripts themselves to show the desired reporting order
of events that might occur in different orders. This patch adds
three types of annotations to deal with (a) test steps that might or
might not complete their waits before the isolationtester can see them
waiting; (b) test steps in different sessions that can legitimately
complete in either order; and (c) NOTIFY messages that might arrive
before or after the completion of a step in another session. We might
need more annotation types later, but this seems to be enough to deal
with the instabilities we've seen in the buildfarm. It also lets us
get rid of all the long delays that were previously used, cutting more
than a minute off the runtime of the isolation tests.
Back-patch to all supported branches, because the buildfarm
instabilities affect all the branches, and because it seems desirable
to keep isolationtester's capabilities the same across all branches
to simplify possible future back-patching of tests.
Discussion: https://postgr.es/m/327948.1623725828@sss.pgh.pa.us
Ordinarily, a pg_policy.polroles array wouldn't list the same role
more than once; but CREATE POLICY does not prevent that. If we
perform DROP OWNED BY on a role that is listed more than once,
RemoveRoleFromObjectPolicy either suffered an assertion failure
or encountered a tuple-updated-by-self error. Rewrite it to cope
correctly with duplicate entries, and add a CommandCounterIncrement
call to prevent the other problem.
Per discussion, there's other cleanup that ought to happen here,
but this seems like the minimum essential fix.
Per bug #17062 from Alexander Lakhin. It's been broken all along,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/17062-11f471ae3199ca23@postgresql.org
This works fine in the "simple Query" code path; but if the
statement is in the plan cache then it's corrupted for future
re-execution. Apply copyObject() to protect the original
tree from modification, as we've done elsewhere.
This narrow fix is applied only to the back branches. In HEAD,
the problem was fixed more generally by commit 7c337b6b5; but
that changed ProcessUtility's API, so it's infeasible to
back-patch.
Per bug #17053 from Charles Samborski.
Discussion: https://postgr.es/m/931771.1623893989@sss.pgh.pa.us
Discussion: https://postgr.es/m/17053-3ca3f501bbc212b4@postgresql.org
The original patch only targeted Python 2.6 and newer, since that is
what we have supported in PostgreSQL 13 and newer. For older
branches, we need to fix it up for older Python versions.
One of the error paths left *members uninitialized. That's not a live
bug, because most callers don't look at *members when the function
returns -1, but let's be tidy. One caller, in heap_lock_tuple(), does
"if (members != NULL) pfree(members)", but AFAICS it never passes an
invalid 'multi' value so it should not reach that error case.
The callers are also a bit inconsistent in their expectations.
heap_lock_tuple() pfrees the 'members' array if it's not-NULL, others
pfree() it if "nmembers >= 0", and others if "nmembers > 0". That's
not a live bug either, because the function should never return 0, but
add an Assert for that to make it more clear. I left the callers alone
for now.
I also moved the line where we set *nmembers. It wasn't wrong before,
but I like to do that right next to the 'return' statement, to make it
clear that it's always set on return.
Also remove one unreachable return statement after ereport(ERROR), for
brevity and for consistency with the similar if-block right after it.
Author: Greg Nancarrow with the additional changes by me
Backpatch-through: 9.6, all supported versions
This is useful for developers to find out if an isolation spec is
over-engineered or if it needs more work by warning at the end of a
test run if a step is not used, generating a failure with extra diffs.
While on it, clean up all the specs which include steps not used in any
permutations to simplify them.
This is a backpatch of 989d23b and 06fdc4e, as it is becoming useful to
make all the branches consistent for an upcoming patch that will improve
the output generated by isolationtester.
Author: Michael Paquier
Reviewed-by: Asim Praveen, Melanie Plageman
Discussion: https://postgr.es/m/20190819080820.GG18166@paquier.xyz
Discussion: https://postgr.es/m/794820.1623872009@sss.pgh.pa.us
Backpatch-through: 9.6
The original purpose of the dry-run mode is to be able to print all the
possible permutations from a spec file, but it has become less useful
since isolation tests have improved regarding deadlock detection as one
step not wanted by the author could block indefinitely now (originally
the step blocked would have been detected rather quickly). Per
discussion, let's remove it.
This is a backpatch of 9903338 for 9.6~12. It is proving to become
useful to have on those branches so as the code gets consistent across
all supported versions, as a matter of improving the output generated by
isolationtester.
Author: Michael Paquier
Reviewed-by: Asim Praveen, Melanie Plageman
Discussion: https://postgr.es/m/20190819080820.GG18166@paquier.xyz
Discussion: https://postgr.es/m/794820.1623872009@sss.pgh.pa.us
Backpatch-through: 9.6
When stuffing a plan from the plancache into a Portal, one is
not supposed to risk throwing an error between GetCachedPlan and
PortalDefineQuery; if that happens, the plan refcount incremented
by GetCachedPlan will be leaked. I managed to break this rule
while refactoring code in 9dbf2b7d7. There is no visible
consequence other than some memory leakage, and since nobody is
very likely to trigger the relevant error conditions many times
in a row, it's not surprising we haven't noticed. Nonetheless,
it's a bug, so rearrange the order of operations to remove the
hazard.
Noted on the way to looking for a better fix for bug #17053.
This mistake is pretty old, so back-patch to all supported
branches.
TestLib::perl2host can take a file argument as well as a directory
argument, so that code becomes substantially simpler. Also add comments
on why we're using forward slashes, and why we're setting
PERL_BADLANG=0.
Discussion: https://postgr.es/m/e9947bcd-20ee-027c-f0fe-01f736b7e345@dunslane.net
During decoding for speculative inserts, we were relying for cleaning
toast hash on confirmation records or next change records. But that
could lead to multiple problems (a) memory leak if there is neither a
confirmation record nor any other record after toast insertion for a
speculative insert in the transaction, (b) error and assertion failures
if the next operation is not an insert/update on the same table.
The fix is to start queuing spec abort change and clean up toast hash
and change record during its processing. Currently, we are queuing the
spec aborts for both toast and main table even though we perform cleanup
while processing the main table's spec abort record. Later, if we have a
way to distinguish between the spec abort record of toast and the main
table, we can avoid queuing the change for spec aborts of toast tables.
Reported-by: Ashutosh Bapat
Author: Dilip Kumar
Reviewed-by: Amit Kapila
Backpatch-through: 9.6, where it was introduced
Discussion: https://postgr.es/m/CAExHW5sPKF-Oovx_qZe4p5oM6Dvof7_P+XgsNAViug15Fm99jA@mail.gmail.com
Recent glibc versions have made mktime() fail if tm_isdst is
inconsistent with the prevailing timezone; in particular it fails for
tm_isdst = 1 when the zone is UTC. (This seems wildly inconsistent
with the POSIX-mandated treatment of "incorrect" values for the other
fields of struct tm, so if you ask me it's a bug, but I bet they'll
say it's intentional.) This has been observed to cause cosmetic
problems when pg_restore'ing an archive created in a different
timezone.
To fix, do mktime() using the field values from the archive, and if
that fails try again with tm_isdst = -1. This will give a result
that's off by the UTC-offset difference from the original zone, but
that was true before, too. It's not terribly critical since we don't
do anything with the result except possibly print it. (Someday we
should flush this entire bit of logic and record a standard-format
timestamp in the archive instead. That's not okay for a back-patched
bug fix, though.)
Also, guard our only other use of mktime() by having initdb's
build_time_t() set tm_isdst = -1 not 0. This case could only have
an issue in zones that are DST year-round; but I think some do exist,
or could in future.
Per report from Wells Oliver. Back-patch to all supported
versions, since any of them might need to run with a newer glibc.
Discussion: https://postgr.es/m/CAOC+FBWDhDHO7G-i1_n_hjRzCnUeFO+H-Czi1y10mFhRWpBrew@mail.gmail.com
Translate path slashes on target directory path. This was confusing old
branches, but is applied to all branches for the sake of uniformity.
Perl is perfectly able to understand paths with forward slashes.
Along the way, restore the previous archive_wait query, for the sake of
uniformity with other tests, per gripe from Tom Lane.
This is similar to the work done in 8279f68 for TestLib.pm, where
environment variables set may cause unwanted failures if using a
temporary installation with pg_regress. The list of variables reset is
adjusted in each stable branch depending on what is supported.
Comments are added to remember that the lists in TestLib.pm and
pg_regress.c had better be kept in sync.
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/YMNR9GYDn+fHlMta@paquier.xyz
Backpatch-through: 9.6
Several TAP tests use poll_query_until() to wait for the postmaster
to restart. They were checking to see if a trivial query
(e.g. "SELECT 1") succeeds. However, that's problematic in the wake
of commit 11e9caff8, because now that we feed said query to psql
via stdin, we risk IPC::Run whining about a SIGPIPE failure if psql
quits before reading the query. Hence, we can't use a nonempty
query in cases where we need to wait for connection failures to
stop happening.
Per the precedent of commits c757a3da0 and 6d41dd045, we can pass
"undef" as the query in such cases to ensure that IPC::Run has
nothing to write. However, then we have to say that the expected
output is empty, and this exposes a deficiency in poll_query_until:
if psql fails altogether and returns empty stdout, poll_query_until
will treat that as a success! That's because, contrary to its
documentation, it makes no actual check for psql failure, looking
neither at the exit status nor at stderr.
To fix that, adjust poll_query_until to insist on empty stderr as
well as a stdout match. (I experimented with checking exit status
instead, but it seems that psql often does exit(1) in cases that we
need to consider successes. That might be something to fix someday,
but it would be a non-back-patchable behavior change.)
Back-patch to v10. The test cases needing this exist only as far
back as v11, but it seems wise to keep poll_query_until's behavior
the same in v10, in case we back-patch another such test case in
future. (9.6 does not currently need this change, because in that
branch poll_query_until can't be told to accept empty stdout as
a success case.)
Per assorted buildfarm failures, mostly on hoverfly.
Discussion: https://postgr.es/m/CAA4eK1+zM6L4QSA1XMvXY_qqWwdUmqkOS1+hWvL8QcYEBGA1Uw@mail.gmail.com
Previously, a zero value for the relfilenode resulted in
a confusing error message about "unexpected duplicate".
This function returns NULL for other invalid relfilenode
values, so zero should be treated likewise.
It's been like this all along, so back-patch to all supported
branches.
Justin Pryzby
Discussion: https://postgr.es/m/20210612023324.GT16435@telsasoft.com
Using an Assert to check the validity of incoming messages is an
extremely poor decision. In a debug build, it should not be that easy
for a broken or malicious remote client to crash the logrep worker.
The consequences could be even worse in non-debug builds, which will
fail to make such checks at all, leading to who-knows-what misbehavior.
Hence, promote every Assert that could possibly be triggered by wrong
or out-of-order replication messages to a full test-and-ereport.
To avoid bloating the set of messages the translation team has to cope
with, establish a policy that replication protocol violation error
reports don't need to be translated. Hence, all the new messages here
use errmsg_internal(). A couple of old messages are changed likewise
for consistency.
Along the way, fix some non-idiomatic or outright wrong uses of
hash_search().
Most of these mistakes are new with the "streaming replication"
patch (commit 464824323), but a couple go back a long way.
Back-patch as appropriate.
Discussion: https://postgr.es/m/1719083.1623351052@sss.pgh.pa.us
Commit caba8f0d43 wasn't quite right for msys, as demonstrated by
several buildfarm animals, including jacana and fairywren. We need to
use the msys perl in the archive command, but call it in such a way that
Windows will understand the path. Furthermore, inside the copy script we
need to convert a Windows path to an msys path.
This variable was present in the list added by 9d660670, but it is not
supported by this branch. Issue noticed while diving into a similar
change for pg_regress.c.
Backpatch-through: 9.6
This only happens if (1) the new standby has no WAL available locally,
(2) the new standby is starting from the old timeline, (3) the promotion
happened in the WAL segment from which the new standby is starting,
(4) the timeline history file for the new timeline is available from
the archive but the WAL files for are not (i.e. this is a race),
(5) the WAL files for the new timeline are available via streaming,
and (6) recovery_target_timeline='latest'.
Commit ee994272ca introduced this
logic and was an improvement over the previous code, but it mishandled
this case. If recovery_target_timeline='latest' and restore_command is
set, validateRecoveryParameters() can change recoveryTargetTLI to be
different from receiveTLI. If streaming is then tried afterward,
expectedTLEs gets initialized with the history of the wrong timeline.
It's supposed to be a list of entries explaining how to get to the
target timeline, but in this case it ends up with a list of entries
explaining how to get to the new standby's original timeline, which
isn't right.
Dilip Kumar and Robert Haas, reviewed by Kyotaro Horiguchi.
Discussion: http://postgr.es/m/CAFiTN-sE-jr=LB8jQuxeqikd-Ux+jHiXyh4YDiZMPedgQKup0g@mail.gmail.com
The set of subcommands supported by \dAp, \do and \dy was described
incorrectly in psql's --help. The documentation was already consistent
with the code.
Reported-by: inoas, from IRC
Author: Matthijs van der Vleuten
Reviewed-by: Neil Chen
Discussion: https://postgr.es/m/6a984e24-2171-4039-9050-92d55e7b23fe@www.fastmail.com
Backpatch-through: 9.6
An incorrectly-encoded multibyte character near the end of a string
could cause various processing loops to run past the string's
terminating NUL, with results ranging from no detectable issue to
a program crash, depending on what happens to be in the following
memory.
This isn't an issue in the server, because we take care to verify
the encoding of strings before doing any interesting processing
on them. However, that lack of care leaked into client-side code
which shouldn't assume that anyone has validated the encoding of
its input.
Although this is certainly a bug worth fixing, the PG security team
elected not to regard it as a security issue, primarily because
any untrusted text should be sanitized by PQescapeLiteral or
the like before being incorporated into a SQL or psql command.
(If an app fails to do so, the same technique can be used to
cause SQL injection, with probably much more dire consequences
than a mere client-program crash.) Those functions were already
made proof against this class of problem, cf CVE-2006-2313.
To fix, invent PQmblenBounded() which is like PQmblen() except it
won't return more than the number of bytes remaining in the string.
In HEAD we can make this a new libpq function, as PQmblen() is.
It seems imprudent to change libpq's API in stable branches though,
so in the back branches define PQmblenBounded as a macro in the files
that need it. (Note that just changing PQmblen's behavior would not
be a good idea; notably, it would completely break the escaping
functions' defense against this exact problem. So we just want a
version for those callers that don't have any better way of handling
this issue.)
Per private report from houjingyi. Back-patch to all supported branches.
Back-patch a minimal subset of commits fffd651e8 and 46912d9b1,
to support strnlen() on all platforms without adding any callers.
This will be needed by a following bug fix.
The Msys shell mangles certain patterns in its command line, so avoid
handing arbitrary SQL to psql on the command line and instead use
IPC::Run's redirection facility for stdin. This pattern is already
mostly whats used, but query_poll_until() was not doing the right thing.
Problem discovered on the buildfarm when a new TAP test failed on msys.
The internal SQL queries used by REFRESH MATERIALIZED VIEW CONCURRENTLY
include some aliases for its diff and temporary relations with
rather-generic names: diff, newdata, newdata2 and mv. Depending on the
queries used for the materialized view, using CONCURRENTLY could lead to
some internal failures if the query and those internal aliases conflict.
Those names have been chosen in 841c29c8. This commit switches instead
to a naming pattern which is less likely going to cause conflicts, based
on an idea from Thomas Munro, by appending _$ to those aliases. This is
not perfect as those new names could still conflict, but at least it has
the advantage to keep the code readable and simple while reducing the
likelihood of conflicts to be close to zero.
Reported-by: Mathis Rudolf
Author: Bharath Rupireddy
Reviewed-by: Bernd Helmle, Thomas Munro, Michael Paquier
Discussion: https://postgr.es/m/109c267a-10d2-3c53-b60e-720fcf44d9e8@credativ.de
Backpatch-through: 9.6
Various environment variables were not getting reset in the TAP tests,
which would cause failures depending on the tests or the environment
variables involved. For example, PGSSL{MAX,MIN}PROTOCOLVERSION could
cause failures in the SSL tests. Even worse, a junk value of
PGCLIENTENCODING makes a server startup fail. The list of variables
reset is adjusted in each stable branch depending on what is supported.
While on it, simplify a bit the code per a suggestion from Andrew
Dunstan, using a list of variables instead of doing single deletions.
Reviewed-by: Andrew Dunstan, Daniel Gustafsson
Discussion: https://postgr.es/m/YLbjjRpucIeZ78VQ@paquier.xyz
Backpatch-through: 9.6
This case should be disallowed, just as FOR UPDATE with a plain
GROUP BY is disallowed; FOR UPDATE only makes sense when each row
of the query result can be identified with a single table row.
However, we missed teaching CheckSelectLocking() to check
groupingSets as well as groupClause, so that it would allow
degenerate grouping sets. That resulted in a bad plan and
a null-pointer dereference in the executor.
Looking around for other instances of the same bug, the only one
I found was in examine_simple_variable(). That'd just lead to
silly estimates, but it should be fixed too.
Per private report from Yaoguang Chen.
Back-patch to all supported branches.
The deliverables of upstream Kerberos on Windows are installed with
paths that do not match our MSVC scripts. First, the include folder was
named "inc/" in our scripts, but the upstream MSIs use "include/".
Second, the build would fail with 64-bit environments as the libraries
are named differently.
This commit adjusts the MSVC scripts to be compatible with the latest
installations of upstream, and I have checked that the compilation was
able to work with the 32-bit and 64-bit installations.
Special thanks to Kondo Yuta for the help in investigating the situation
in hamerkop, which had an incorrect configuration for the GSS
compilation.
Reported-by: Brian Ye
Discussion: https://postgr.es/m/162128202219.27274.12616756784952017465@wrigleys.postgresql.org
Backpatch-through: 9.6
SSL renegotiation is already disabled as of 48d23c72, however this does
not prevent the server to comply with a client willing to use
renegotiation. In the last couple of years, renegotiation had its set
of security issues and flaws (like the recent CVE-2021-3449), and it
could be possible to crash the backend with a client attempting
renegotiation.
This commit takes one extra step by disabling renegotiation in the
backend in the same way as SSL compression (f9264d15) or tickets
(97d3a0b0). OpenSSL 1.1.0h has added an option named
SSL_OP_NO_RENEGOTIATION able to achieve that. In older versions
there is an option called SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS that
was undocumented, and could be set within the SSL object created when
the TLS connection opens, but I have decided not to use it, as it feels
trickier to rely on, and it is not official. Note that this option is
not usable in OpenSSL < 1.1.0h as the internal contents of the *SSL
object are hidden to applications.
SSL renegotiation concerns protocols up to TLSv1.2.
Per original report from Robert Haas, with a patch based on a suggestion
by Andres Freund.
Author: Michael Paquier
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/YKZBXx7RhU74FlTE@paquier.xyz
Backpatch-through: 9.6
"typename" is a C++ keyword, so pg_upgrade.h fails to compile in C++.
Fortunately, there seems no likely reason for somebody to need to
do that. Nonetheless, it's project policy that all .h files should
pass cpluspluscheck, so rename the argument to fix that.
Oversight in 57c081de0; back-patch as that was. (The policy requiring
pg_upgrade.h to pass cpluspluscheck only goes back to v12, but it
seems best to keep this code looking the same in all branches.)
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
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
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
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
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
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
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 backpack 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
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
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.)
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
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
"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
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
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.
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
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
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.)
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 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
Both heapgettup() and heapgettup_pagemode() incorrectly set the first page
to scan in a backward scan in which the number of pages to scan was
specified by heap_setscanlimits(). The code incorrectly started the scan
at the end of the relation when startBlk was 0, or otherwise at
startBlk - 1, neither of which is correct when only scanning a subset of
pages.
The fix here checks if heap_setscanlimits() has changed the number of
pages to scan and if so we set the first page to scan as the final page in
the specified range during backward scans.
Proper adjustment of this code was forgotten when heap_setscanlimits() was
added in 7516f5259 back in 9.5. However, practice, nowhere in core code
performs backward scans after having used heap_setscanlimits(), yet, it is
possible an extension uses the heap functions in this way, hence
backpatch.
An upcoming patch does use heap_setscanlimits() with backward scans, so
this must be fixed before that can go in.
Author: David Rowley
Discussion: https://postgr.es/m/CAApHDvpGc9h0_oVD2CtgBcxCS1N-qDYZSeBRnUh+0CWJA9cMaA@mail.gmail.com
Backpatch-through: 9.5, all supported versions
DST law changes in Russia (Volgograd zone) and South Sudan.
Historical corrections for Australia, Bahamas, Belize, Bermuda,
Ghana, Israel, Kenya, Nigeria, Palestine, Seychelles, and Vanuatu.
Notably, the Australia/Currie zone has been corrected to the point
where it is identical to Australia/Hobart.
It emerges that in some phases of the moon (perhaps to do with
directory entry order?), xcrun will report that the SDK path is
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk
which is normally a symlink to a version-numbered sibling directory.
Our heuristic to skip non-version-numbered pathnames was rejecting
that, which is the wrong thing to do. We'd still like to end up
with a version-numbered PG_SYSROOT value, but we can have that by
dereferencing the symlink.
Like the previous fix, back-patch to all supported versions.
Discussion: https://postgr.es/m/522433.1611089678@sss.pgh.pa.us
Specifying duplicated objects in this command would lead to unique
constraint violations in pg_default_acl or "tuple already updated by
self" errors. Similarly to GRANT/REVOKE, increment the command ID after
each subcommand processing to allow this case to work transparently.
A regression test is added by tweaking one of the existing queries of
privileges.sql to stress this case.
Reported-by: Andrus
Author: Michael Paquier
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/ae2a7dc1-9d71-8cba-3bb9-e4cb7eb1f44e@hot.ee
Backpatch-through: 9.5
Somebody extended search_plan_tree() to treat MergeAppend exactly
like Append, which is 100% wrong, because unlike Append we can't
assume that only one input node is actively returning tuples.
Hence a cursor using a MergeAppend across a UNION ALL or inheritance
tree could falsely match a WHERE CURRENT OF query at a row that
isn't actually the cursor's current output row, but coincidentally
has the same TID (in a different table) as the current output row.
Delete the faulty code; this means that such a case will now return
an error like 'cursor "foo" is not a simply updatable scan of table
"bar"', instead of silently misbehaving. Users should not find that
surprising though, as the same cursor query could have failed that way
already depending on the chosen plan. (It would fail like that if the
sort were done with an explicit Sort node instead of MergeAppend.)
Expand the clearly-inadequate commentary to be more explicit about
what this code is doing, in hopes of forestalling future mistakes.
It's been like this for awhile, so back-patch to all supported
branches.
Discussion: https://postgr.es/m/482865.1611075182@sss.pgh.pa.us
execCurrent.c's search_plan_tree() assumed that ForeignScanStates
and CustomScanStates necessarily have a valid ss_currentRelation.
This is demonstrably untrue for postgres_fdw's remote join and
remote aggregation plans, and non-leaf custom scans might not have
an identifiable scan relation either. Avoid crashing by ignoring
such nodes when the field is null.
This solution will lead to errors like 'cursor "foo" is not a
simply updatable scan of table "bar"' in cases where maybe we
could have allowed WHERE CURRENT OF to work. That's not an issue
for postgres_fdw's usages, since joins or aggregations would render
WHERE CURRENT OF invalid anyway. But an otherwise-transparent
upper level custom scan node might find this annoying. When and if
someone cares to expend work on such a scenario, we could invent a
custom-scan-provider callback to determine what's safe.
Report and patch by David Geier, commentary by me. It's been like
this for awhile, so back-patch to all supported branches.
Discussion: https://postgr.es/m/0253344d-9bdd-11c4-7f0d-d88c02cd7991@swarm64.com
The context is an object that no longer bears some aclitem that it bore
initially. (A user issued REVOKE or GRANT statements upon the object.)
pg_dump is forming SQL to reproduce the object ACL. Since initdb
creates no ACL bearing GRANT OPTION, reaching this bug requires an
extension where the creation script establishes such an ACL. No PGXN
extension does that. If an installation did reach the bug, pg_dump
would have omitted a semicolon, causing a REVOKE and the next SQL
statement to fail. Separately, since the affected code exists to
eliminate an entire aclitem, it wants plain REVOKE, not REVOKE GRANT
OPTION FOR. Back-patch to 9.6, where commit
23f34fa4ba first appeared.
Discussion: https://postgr.es/m/20210109102423.GA160022@rfd.leadboat.com
Every core SLRU wraps around. With the exception of pg_notify, the wrap
point can fall in the middle of a page. Account for this in the
PagePrecedes callback specification and in SimpleLruTruncate()'s use of
said callback. Update each callback implementation to fit the new
specification. This changes SerialPagePrecedesLogically() from the
style of asyncQueuePagePrecedes() to the style of CLOGPagePrecedes().
(Whereas pg_clog and pg_serial share a key space, pg_serial is nothing
like pg_notify.) The bug fixed here has the same symptoms and user
followup steps as 592a589a04. Back-patch
to 9.5 (all supported versions).
Reviewed by Andrey Borodin and (in earlier versions) by Tom Lane.
Discussion: https://postgr.es/m/20190202083822.GC32531@gust.leadboat.com
Add a check that CREATE STATISTICS does not add extended statistics on
system catalogs, similarly to indexes etc. It can be overriden using
the allow_system_table_mods GUC.
This bug exists since 7b504eb282, adding the extended statistics, so
backpatch all the way back to PostgreSQL 10.
Author: Tomas Vondra
Reported-by: Dean Rasheed
Backpatch-through: 10
Discussion: https://postgr.es/m/CAEZATCXAPrrOKwEsyZKQ4uzzJQWBCt6QAvOcgqRGdWwT1zb%2BrQ%40mail.gmail.com
In cases where Xcode is newer than the underlying macOS version,
asking xcodebuild for the SDK path will produce a pointer to the
SDK shipped with Xcode, which may end up building code that does
not work on the underlying macOS version. It appears that in
such cases, xcodebuild's answer also fails to match the default
behavior of Apple's compiler: assuming one has installed Xcode's
"command line tools", there will be an SDK for the OS's own version
in /Library/Developer/CommandLineTools, and the compiler will
default to using that. This is all pretty poorly documented,
but experimentation suggests that "xcrun --show-sdk-path" gives
the sysroot path that the compiler is actually using, at least
in some cases. Hence, try that first, but revert to xcodebuild
if xcrun fails (in very old Xcode, it is missing or lacks the
--show-sdk-path switch).
Also, "xcrun --show-sdk-path" may give a path that is valid but lacks
any OS version identifier. We don't really want that, since most
of the motivation for wiring -isysroot into the build flags at all
is to ensure that all parts of a PG installation are built against
the same SDK, even when considering extensions built later and/or on
a different machine. Insist on finding "N.N" in the directory name
before accepting the result. (Adding "--sdk macosx" to the xcrun
call seems to produce the same answer as xcodebuild, but usually
more quickly because it's cached, so we also try that as a fallback.)
The core reason why we don't want to use Xcode's default SDK in cases
like this is that Apple's technology for introducing new syscalls
does not play nice with Autoconf: for example, configure will think
that preadv/pwritev exist when using a Big Sur SDK, even when building
on an older macOS version where they don't exist. It'd be nice to
have a better solution to that problem, but this patch doesn't attempt
to fix that.
Per report from Sergey Shinderuk. Back-patch to all supported versions.
Discussion: https://postgr.es/m/ed3b8e5d-0da8-6ebd-fd1c-e0ac80a4b204@postgrespro.ru
This is the same fix as commit 9eabfe300 applied to INDEX ATTACH
entries, but for table-to-publication attachments. As in that
case, even though the backend doesn't record "ownership" of the
attachment, we still ought to label it in the dump archive with
the role name that should run the ALTER PUBLICATION command.
The existing behavior causes the ALTER to be done by the original
role that started the restore; that will usually work fine, but
there may be corner cases where it fails.
The bulk of the patch is concerned with changing struct
PublicationRelInfo to include a pointer to the associated
PublicationInfo object, so that we can get the owner's name
out of that when the time comes. While at it, I rewrote
getPublicationTables() to do just one query of pg_publication_rel,
not one per table.
Back-patch to v10 where this code was introduced.
Discussion: https://postgr.es/m/1165710.1610473242@sss.pgh.pa.us
brenext(), when parsing a '*' quantifier, forgot to return any "value"
for the token; per the equivalent case in next(), it should return
value 1 to indicate that greedy rather than non-greedy behavior is
wanted. The result is that the compiled regexp could behave like 'x*?'
rather than the intended 'x*', if we were unlucky enough to have
a zero in v->nextvalue at this point. That seems to happen with some
reliability if we have '.*' at the beginning of a BRE-mode regexp,
although that depends on the initial contents of a stack-allocated
struct, so it's not guaranteed to fail.
Found by Alexander Lakhin using valgrind testing. This bug seems
to be aboriginal in Spencer's code, so back-patch all the way.
Discussion: https://postgr.es/m/16814-6c5e3edd2bdf0d50@postgresql.org
On reflection, the order of operations in PostgresMain() is wrong.
These timeouts ought to be shut down before, not after, we do the
post-command-read CHECK_FOR_INTERRUPTS, to guarantee that any
timeout error will be detected there rather than at some ill-defined
later point (possibly after having wasted a lot of work).
This is really an error in the original idle_in_transaction_timeout
patch, so back-patch to 9.6 where that was introduced.
The deadlocks that the recovery conflict on lock is involved in can
happen between hot-standby backends and the startup process.
If a backend takes an access exclusive lock on the table and which
finally triggers the deadlock, that deadlock can be detected
as expected. On the other hand, previously, if the startup process
took an access exclusive lock and which finally triggered the deadlock,
that deadlock could not be detected and could remain even after
deadlock_timeout passed. This is a bug.
The cause of this bug was that the code for handling the recovery
conflict on lock didn't take care of deadlock case at all. It assumed
that deadlocks involving the startup process and backends were able
to be detected by the deadlock detector invoked within backends.
But this assumption was incorrect. The startup process also should
have invoked the deadlock detector if necessary.
To fix this bug, this commit makes the startup process invoke
the deadlock detector if deadlock_timeout is reached while handling
the recovery conflict on lock. Specifically, in that case, the startup
process requests all the backends holding the conflicting locks to
check themselves for deadlocks.
Back-patch to v9.6. v9.5 has also this bug, but per discussion we decided
not to back-patch the fix to v9.5. Because v9.5 doesn't have some
infrastructure codes (e.g., 37c54863cf) that this bug fix patch depends on.
We can apply those codes for the back-patch, but since the next minor
version release is the final one for v9.5, it's risky to do that. If we
unexpectedly introduce new bug to v9.5 by the back-patch, there is no
chance to fix that. We determined that the back-patch to v9.5 would give
more risk than gain.
Author: Fujii Masao
Reviewed-by: Bertrand Drouvot, Masahiko Sawada, Kyotaro Horiguchi
Discussion: https://postgr.es/m/4041d6b6-cf24-a120-36fa-1294220f8243@oss.nttdata.com
In power_var_int(), the computation of the number of significant
digits to use in the computation used log(Abs(exp)), which isn't safe
because Abs(exp) returns INT_MIN when exp is INT_MIN. Use fabs()
instead of Abs(), so that the exponent is cast to a double before the
absolute value is taken.
Back-patch to 9.6, where this was introduced (by 7d9a4737c2).
Discussion: https://postgr.es/m/CAEZATCVd6pMkz=BrZEgBKyqqJrt2xghr=fNc8+Z=5xC6cgWrWA@mail.gmail.com
The code in charge of processing a single invalidation message has been
using since 568d413 the structure for relation mapping messages. This
had fortunately no consequence as both locate the database ID at the
same location, but it could become a problem in the future if this area
of the code changes.
Author: Konstantin Knizhnik
Discussion: https://postgr.es/m/8044c223-4d3a-2cdb-42bf-29940840ce94@postgrespro.ru
Backpatch-through: 9.5
This makes existing sessions reflect "ALTER ROLE ... [NO]INHERIT" as
quickly as they have been reflecting "GRANT role_name". Back-patch to
9.5 (all supported versions).
Reviewed by Nathan Bossart.
Discussion: https://postgr.es/m/20201221095028.GB3777719@rfd.leadboat.com
If a database shutdown (smart or fast) is commanded between the time
some process decides to request a new background worker and the time
that the postmaster can launch that worker, then nothing happens
because the postmaster won't launch any bgworkers once it's exited
PM_RUN state. This is fine ... unless the requesting process is
waiting for that worker to finish (or even for it to start); in that
case the requestor is stuck, and only manual intervention will get us
to the point of being able to shut down.
To fix, cancel pending requests for workers when the postmaster sends
shutdown (SIGTERM) signals, and similarly cancel any new requests that
arrive after that point. (We can optimize things slightly by only
doing the cancellation for workers that have waiters.) To fit within
the existing bgworker APIs, the "cancel" is made to look like the
worker was started and immediately stopped, causing deregistration of
the bgworker entry. Waiting processes would have to deal with
premature worker exit anyway, so this should introduce no bugs that
weren't there before. We do have a side effect that registration
records for restartable bgworkers might disappear when theoretically
they should have remained in place; but since we're shutting down,
that shouldn't matter.
Back-patch to v10. There might be value in putting this into 9.6
as well, but the management of bgworkers is a bit different there
(notably see 8ff518699) and I'm not convinced it's worth the effort
to validate the patch for that branch.
Discussion: https://postgr.es/m/661570.1608673226@sss.pgh.pa.us
The parsing of this parameter has been using strtoul(), which is not
portable across platforms. On most Unix platforms, unsigned long has a
size of 64 bits, while on Windows it is 32 bits. It is common in
recovery scenarios to rely on the output of txid_current() or even the
newer pg_current_xact_id() to get a transaction ID for setting up
recovery_target_xid. The value returned by those functions includes the
epoch in the computed result, which would cause strtoul() to fail where
unsigned long has a size of 32 bits once the epoch is incremented.
WAL records and 2PC data include only information about 32-bit XIDs and
it is not possible to have XIDs across more than one epoch, so
discarding the high bits from the transaction ID set has no impact on
recovery. On the contrary, the use of strtoul() prevents a consistent
behavior across platforms depending on the size of unsigned long.
This commit changes the parsing of recovery_target_xid to use
pg_strtouint64() instead, available down to 9.6. There is one TAP test
stressing recovery with recovery_target_xid, where a tweak based on
pg_reset{xlog,wal} is added to bump the XID epoch so as this change gets
tested, as per an idea from Alexander Lakhin.
Reported-by: Alexander Lakhin
Discussion: https://postgr.es/m/16780-107fd0c0385b1035@postgresql.org
Backpatch-through: 9.6
The jsonb || jsonb operator arbitrarily rejected certain combinations
of scalar and non-scalar inputs, while being willing to concatenate
other combinations. This was of course quite undocumented. Rather
than trying to document it, let's just remove the restriction,
creating a uniform rule that unless we are handling an object-to-object
concatenation, non-array inputs are converted to one-element arrays,
resulting in an array-to-array concatenation. (This does not change
the behavior for any case that didn't throw an error before.)
Per complaint from Joel Jacobson. Back-patch to all supported branches.
Discussion: https://postgr.es/m/163099.1608312033@sss.pgh.pa.us
A narrow reading of the C standard says that memcpy(x,x,n) is undefined,
although it's hard to envision an implementation that would really
misbehave. However, analysis tools such as valgrind might whine about
this; accordingly, let's band-aid relmapper.c to not do it.
See also 5b630501e, d3f4e8a8a, ad7b48ea0, and other similar fixes.
Apparently, none of those folk tried valgrinding initdb? This has been
like this for long enough that I'm surprised it hasn't been reported
before.
Back-patch, just in case anybody wants to use a back branch on a platform
that complains about this; we back-patched those earlier fixes too.
Discussion: https://postgr.es/m/161790.1608310142@sss.pgh.pa.us
array_get_element and array_get_slice qualify as leakproof, since
they will silently return NULL for bogus subscripts. But
array_set_element and array_set_slice throw errors for such cases,
making them clearly not leakproof. contain_leaked_vars was evidently
written with only the former case in mind, as it gave the wrong answer
for assignment SubscriptingRefs (nee ArrayRefs).
This would be a live security bug, were it not that assignment
SubscriptingRefs can only occur in INSERT and UPDATE target lists,
while we only care about leakproofness for qual expressions; so the
wrong answer can't occur in practice. Still, that's a rather shaky
answer for a security-related question; and maybe in future somebody
will want to ask about leakproofness of a tlist. So it seems wise to
fix and even back-patch this correction.
(We would need some change here anyway for the upcoming
generic-subscripting patch, since extensions might make different
tradeoffs about whether to throw errors. Commit 558d77f20 attempted
to lay groundwork for that by asking check_functions_in_node whether a
SubscriptingRef contains leaky functions; but that idea fails now that
the implementation methods of a SubscriptingRef are not SQL-visible
functions that could be marked leakproof or not.)
Back-patch to 9.6. While 9.5 has the same issue, the code's a bit
different. It seems quite unlikely that we'd introduce any actual bug
in the short time 9.5 has left to live, so the work/risk/reward balance
isn't attractive for changing 9.5.
Discussion: https://postgr.es/m/3143742.1607368115@sss.pgh.pa.us
pg_rewind looks at the control file to check what timeline a server is on.
But promotion doesn't immediately write a checkpoint, it merely writes
an end-of-recovery WAL record. If pg_rewind runs immediately after
promotion, before the checkpoint has completed, it will think think that
the server is still on the earlier timeline. We ran into this issue a long
time ago already, see commit 484a848a73.
It's a bit bogus that pg_rewind doesn't determine the timeline correctly
until the end-of-recovery checkpoint has completed. We probably should
fix that. But for now work around it by waiting for the checkpoint
to complete before running pg_rewind, like we did in commit 484a848a73.
In the passing, tidy up the new test a little bit. Rerder the INSERTs so
that the comments make more sense, remove a spurious CHECKPOINT call after
pg_rewind has already run, and add --debug option, so that if this fails
again, we'll have more data.
Per buildfarm failure at https://buildfarm.postgresql.org/cgi-bin/show_stage_log.pl?nm=rorqual&dt=2020-12-06%2018%3A32%3A19&stg=pg_rewind-check.
Backpatch to all supported versions.
Discussion: https://www.postgresql.org/message-id/1713707e-e318-761c-d287-5b6a4aa807e8@iki.fi
Buildfarm has been failing sporadically on the new test. I was able to
reproduce this by adding a random 0-10 s delay in the walreceiver, just
before it connects to the primary. There's a race condition where node_3
is promoted before it has fully caught up with node_1, leading to diverged
timelines. When node_1 is later reconfigured as standby following node_3,
it fails to catch up:
LOG: primary server contains no more WAL on requested timeline 1
LOG: new timeline 2 forked off current database system timeline 1 before current recovery point 0/30000A0
That's the situation where you'd need to use pg_rewind, but in this case
it happens already when we are just setting up the actual pg_rewind
scenario we want to test, so change the test so that it waits until
node_3 is connected and fully caught up before promoting it, so that you
get a clean, controlled failover.
Also rewrite some of the comments, for clarity. The existing comments
detailed what each step in the test did, but didn't give a good overview
of the situation the steps were trying to create.
For reasons I don't understand, the test setup had to be written slightly
differently in 9.6 and 9.5 than in later versions. The 9.5/9.6 version
needed node 1 to be reinitialized from backup, whereas in later versions
it could be shut down and reconfigured to be a standby. But even 9.5 should
support "clean switchover", where primary makes sure that pending WAL is
replicated to standby on shutdown. It would be nice to figure out what's
going on there, but that's independent of pg_rewind and the scenario that
this test tests.
Discussion: https://www.postgresql.org/message-id/b0a3b95b-82d2-6089-6892-40570f8c5e60%40iki.fi
If the target is a standby server, its WAL doesn't end at the last
checkpoint record, but at minRecoveryPoint. We must scan all the
WAL from the last common checkpoint all the way up to minRecoveryPoint
for modified pages, and also consider that portion when determining
whether the server needs rewinding.
Backpatch to all supported versions.
Author: Ian Barwick and me
Discussion: https://www.postgresql.org/message-id/CABvVfJU-LDWvoz4-Yow3Ay5LZYTuPD7eSjjE4kGyNZpXC6FrVQ%40mail.gmail.com
As it stood, expandTableLikeClause() re-did the same relation_openrv
call that transformTableLikeClause() had done. However there are
scenarios where this would not find the same table as expected.
We hold lock on the LIKE source table, so it can't be renamed or
dropped, but another table could appear before it in the search path.
This explains the odd behavior reported in bug #16758 when cloning a
table as a temp table of the same name. This case worked as expected
before commit 502898192 introduced the need to open the source table
twice, so we should fix it.
To make really sure we get the same table, let's re-open it by OID not
name. That requires adding an OID field to struct TableLikeClause,
which is a little nervous-making from an ABI standpoint, but as long
as it's at the end I don't think there's any serious risk.
Per bug #16758 from Marc Boeren. Like the previous patch,
back-patch to all supported branches.
Discussion: https://postgr.es/m/16758-840e84a6cfab276d@postgresql.org
When committing a transaction that dropped a relation, we previously
truncated only the first segment file to free up disk space (the one
that won't be unlinked until the next checkpoint).
Truncate higher numbered segments too, even though we unlink them on
commit. This frees the disk space immediately, even if other backends
have open file descriptors and might take a long time to get around to
handling shared invalidation events and closing them. Also extend the
same behavior to the first segment, in recovery.
Back-patch to all supported releases.
Bug: #16663
Reported-by: Denis Patron <denis.patron@previnet.it>
Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>
Reviewed-by: Neil Chen <carpenter.nail.cz@gmail.com>
Reviewed-by: David Zhang <david.zhang@highgo.ca>
Discussion: https://postgr.es/m/16663-fe97ccf9932fc800%40postgresql.org
If a PlaceHolderVar is to be evaluated at a join relation, but
its value is only needed there and not at higher levels, we neglected
to update the joinrel's direct_lateral_relids to include the PHV's
source rel. This causes problems because join_is_legal() then won't
allow joining the joinrel to the PHV's source rel at all, leading
to "failed to build any N-way joins" planner failures.
Per report from Andreas Seltenreich. Back-patch to 9.5
where the problem originated.
Discussion: https://postgr.es/m/87blfgqa4t.fsf@aurora.ydns.eu
Through my misreading of what the existing code actually did,
commits 85c54287a et al. broke psql's behavior for the case where
"\c connstring" provides a password in the connstring. We should
use that password in such a case, but as of 85c54287a we ignored it
(and instead, prompted for a password).
Commit 94929f1cf fixed that in HEAD, but since I thought it was
cleaning up a longstanding misbehavior and not one I'd just created,
I didn't back-patch it.
Hence, back-patch the portions of 94929f1cf having to do with
password management. In addition to fixing the introduced bug,
this means that "\c -reuse-previous=on connstring" will allow
re-use of an existing connection's password if the connstring
doesn't change user/host/port. That didn't happen before, but
it seems like a bug fix, and anyway I'm loath to have significant
differences in this code across versions.
Also fix an error with the same root cause about whether or not to
override a connstring's setting of client_encoding. As of 85c54287a
we always did so; restore the previous behavior of overriding only
when stdin/stdout are a terminal and there's no environment setting
of PGCLIENTENCODING. (I find that definition a bit surprising, but
right now doesn't seem like the time to revisit it.)
Per bug #16746 from Krzysztof Gradek. As with the previous patch,
back-patch to all supported branches.
Discussion: https://postgr.es/m/16746-44b30e2edf4335d4@postgresql.org
Commit 566372b3d fixed some race conditions involving concurrent
SimpleLruTruncate calls, but it introduced new ones in async.c.
A newly-listening backend could attempt to read Notify SLRU pages that
were in process of being truncated, possibly causing an error. Also,
the QUEUE_TAIL pointer could become set to a value that's not equal to
the queue position of any backend. While that's fairly harmless in
v13 and up (thanks to commit 51004c717), in older branches it resulted
in near-permanent disabling of the queue truncation logic, so that
continued use of NOTIFY led to queue-fill warnings and eventual
inability to send any more notifies. (A server restart is enough to
make that go away, but it's still pretty unpleasant.)
The core of the problem is confusion about whether QUEUE_TAIL
represents the "logical" tail of the queue (i.e., the oldest
still-interesting data) or the "physical" tail (the oldest data we've
not yet truncated away). To fix, split that into two variables.
QUEUE_TAIL regains its definition as the logical tail, and we
introduce a new variable to track the oldest un-truncated page.
Per report from Mikael Gustavsson. Like the previous patch,
back-patch to all supported branches.
Discussion: https://postgr.es/m/1b8561412e8a4f038d7a491c8b922788@smhi.se
Previously this code assumed that all IndexScan nodes supported
mark/restore, which is not true since it depends on optional index AM
support functions. This could lead to errors about missing support
functions in rare edge cases of mergejoins with no sort keys, where an
unordered non-btree index scan was placed on the inner path without a
protecting Materialize node. (Normally, the fact that merge join
requires ordered input would avoid this error.)
Backpatch all the way since this bug is ancient.
Per report from Eugen Konkov on irc.
Discussion: https://postgr.es/m/87o8jn50be.fsf@news-spur.riddles.org.uk
We previously put the -isysroot switch only into CPPFLAGS, theorizing
that it was only needed to find the right copies of include files.
However, it seems that we also need to use it while linking programs,
to find the right stub ".tbd" files for libraries. We got away
without that up to now, but apparently that was mostly luck. It may
also be that failures are only observed when the Xcode version is
noticeably out of sync with the host macOS version; the case that's
prompting action right now is that builds fail when using latest Xcode
(12.2) on macOS Catalina, even though it's fine on Big Sur.
Hence, add -isysroot to LDFLAGS as well. (It seems that the more
common practice is to put it in CFLAGS, whence it'd be included at
both compile and link steps. However, we can't mess with CFLAGS in
the platform template file without confusing configure's logic for
choosing default CFLAGS.)
Back-patch of 49407dc32 into all supported branches.
Report and patch by James Hilliard (some cosmetic mods by me)
Discussion: https://postgr.es/m/20201120003314.20560-1-james.hilliard1@gmail.com
Commit 502898192 was too careless about the order of execution of the
additional ALTER TABLE operations generated by expandTableLikeClause.
It just stuck them all at the end, which seems okay for most purposes.
But it falls down in the case where LIKE is importing a primary key
or unique index and the outer CREATE TABLE includes a FOREIGN KEY
constraint that needs to depend on that index. Weird as that is,
it used to work, so we ought to keep it working.
To fix, make parse_utilcmd.c insert LIKE clauses between index-creation
and FK-creation commands in the transformed list of commands, and change
utility.c so that the commands generated by expandTableLikeClause are
executed immediately not at the end. One could imagine scenarios where
this wouldn't work either; but currently expandTableLikeClause only
makes column default expressions, CHECK constraints, and indexes, and
this ordering seems fine for those.
Per bug #16730 from Sofoklis Papasofokli. Like the previous patch,
back-patch to all supported branches.
Discussion: https://postgr.es/m/16730-b902f7e6e0276b30@postgresql.org
Otherwise, if FDDEBUG is enabled, the debugging output fails because
it tries to read the fileName, which isn't set up yet (and should in
fact always be NULL).
AFAICT, this has been wrong since Berkeley. Before 96bf88d52,
it would accidentally fail to crash on platforms where snprintf()
is forgiving about being passed a NULL pointer for %s; but the
file name intended to be included in the debug output wouldn't
ever have shown up.
Report and fix by Greg Nancarrow. Although this is only visibly
broken in custom-made builds, it still seems worth back-patching
to all supported branches, as the FDDEBUG code is pretty useless
as it stands.
Discussion: https://postgr.es/m/CAJcOf-cUDgm9qYtC_B6XrC6MktMPNRby2p61EtSGZKnfotMArw@mail.gmail.com
Document that though the history file content is marked as bytea, it is
the same a text, and neither is btyea-escaped or encoding converted.
Reported-by: Brar Piening
Discussion: https://postgr.es/m/6a1b9cd9-17e3-df67-be55-86102af6bdf5@gmx.de
Backpatch-through: 13 - 9.5 (not master)
