This patch allows PREPARE-time decoding of two-phase transactions (if the
output plugin supports this capability), in which case the transactions
are replayed at PREPARE and then committed later when COMMIT PREPARED
arrives.
Now that we decode the changes before the commit, the concurrent aborts
may cause failures when the output plugin consults catalogs (both system
and user-defined).
We detect such failures with a special sqlerrcode
ERRCODE_TRANSACTION_ROLLBACK introduced by commit 7259736a6e and stop
decoding the remaining changes. Then we rollback the changes when rollback
prepared is encountered.
Author: Ajin Cherian and Amit Kapila based on previous work by Nikhil Sontakke and Stas Kelvich
Reviewed-by: Amit Kapila, Peter Smith, Sawada Masahiko, Arseny Sher, and Dilip Kumar
Tested-by: Takamichi Osumi
Discussion:
https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ruhttps://postgr.es/m/CAMGcDxeqEpWj3fTXwqhSwBdXd2RS9jzwWscO-XbeCfso6ts3+Q@mail.gmail.com
Since at least 2001 we've used putenv() and avoided setenv(), on the
grounds that the latter was unportable and not in POSIX. However,
POSIX added it that same year, and by now the situation has reversed:
setenv() is probably more portable than putenv(), since POSIX now
treats the latter as not being a core function. And setenv() has
cleaner semantics too. So, let's reverse that old policy.
This commit adds a simple src/port/ implementation of setenv() for
any stragglers (we have one in the buildfarm, but I'd not be surprised
if that code is never used in the field). More importantly, extend
win32env.c to also support setenv(). Then, replace usages of putenv()
with setenv(), and get rid of some ad-hoc implementations of setenv()
wannabees.
Also, adjust our src/port/ implementation of unsetenv() to follow the
POSIX spec that it returns an error indicator, rather than returning
void as per the ancient BSD convention. I don't feel a need to make
all the call sites check for errors, but the portability stub ought
to match real-world practice.
Discussion: https://postgr.es/m/2065122.1609212051@sss.pgh.pa.us
This adds six methods to the output plugin API, adding support for
streaming changes of two-phase transactions at prepare time.
* begin_prepare
* filter_prepare
* prepare
* commit_prepared
* rollback_prepared
* stream_prepare
Most of this is a simple extension of the existing methods, with the
semantic difference that the transaction is not yet committed and maybe
aborted later.
Until now two-phase transactions were translated into regular transactions
on the subscriber, and the GID was not forwarded to it. None of the
two-phase commands were communicated to the subscriber.
This patch provides the infrastructure for logical decoding plugins to be
informed of two-phase commands Like PREPARE TRANSACTION, COMMIT PREPARED
and ROLLBACK PREPARED commands with the corresponding GID.
This also extends the 'test_decoding' plugin, implementing these new
methods.
This commit simply adds these new APIs and the upcoming patch to "allow
the decoding at prepare time in ReorderBuffer" will use these APIs.
Author: Ajin Cherian and Amit Kapila based on previous work by Nikhil Sontakke and Stas Kelvich
Reviewed-by: Amit Kapila, Peter Smith, Sawada Masahiko, and Dilip Kumar
Discussion:
https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ruhttps://postgr.es/m/CAMGcDxeqEpWj3fTXwqhSwBdXd2RS9jzwWscO-XbeCfso6ts3+Q@mail.gmail.com
Those two modules included references to libpq's source path, without
using anything from libpq. Some copy-pastos done when each module was
created are likely at the origin of those useless references (aecf5ee
for old_snapshot, fe59e56 for adminpack).
Reviewed-by: Tom Lane, David Rowley
Discussion: https://postgr.es/m/X+LQpfLyk7jgzUki@paquier.xyz
In postgres_fdw, the cached connections to foreign servers will not be
closed until the local session exits if the user mappings or foreign servers
that those connections depend on are dropped. Those connections can be
leaked.
To fix that connection leak issue, after a change to a pg_foreign_server
or pg_user_mapping catalog entry, this commit makes postgres_fdw close
the connections depending on that entry immediately if current
transaction has not used those connections yet. Otherwise, mark those
connections as invalid and then close them at the end of current transaction,
since they cannot be closed in the midst of the transaction using them.
Closed connections will be remade at the next opportunity if necessary.
Back-patch to all supported branches.
Author: Bharath Rupireddy
Reviewed-by: Zhihong Yu, Zhijie Hou, Fujii Masao
Discussion: https://postgr.es/m/CALj2ACVNcGH_6qLY-4_tXz8JLvA+4yeBThRfxMz7Oxbk1aHcpQ@mail.gmail.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
Bad things happen if the DBA issues "pg_ctl stop -m fast" before
autoprewarm finishes loading its list of blocks to prewarm.
The current worker process successfully terminates early, but
(if this wasn't the last database with blocks to prewarm) the
leader process will just try to launch another worker for the
next database. Since the postmaster is now in PM_WAIT_BACKENDS
state, it ignores the launch request, and the leader just sits
until it's killed manually.
This is mostly the fault of our half-baked design for launching
background workers, but a proper fix for that is likely to be
too invasive to be back-patchable. To ameliorate the situation,
fix apw_load_buffers() to check whether SIGTERM has arrived
just before trying to launch another worker. That leaves us with
only a very narrow window in each worker launch where SIGTERM
could occur between the launch request and successful worker start.
Another issue is that if the leader process does manage to exit,
it unconditionally rewrites autoprewarm.blocks with only the
blocks currently in shared buffers, thus forgetting any blocks
that we hadn't reached yet while prewarming. This seems quite
unhelpful, since the next database start will then not have the
expected prewarming benefit. Fix it to not modify the file if
we shut down before the initial load attempt is complete.
Per bug #16785 from John Thompson. Back-patch to v11 where
the autoprewarm code was introduced.
Discussion: https://postgr.es/m/16785-c0207d8c67fb5f25@postgresql.org
The same logic was present for collation commands, SASLprep and
pgcrypto, so this removes some code.
Author: Michael Paquier
Reviewed-by: Stephen Frost, Heikki Linnakangas
Discussion: https://postgr.es/m/X9womIn6rne6Gud2@paquier.xyz
This commit adds "stats_reset" column into the pg_stat_statements_info
view. This column indicates the time at which all statistics in the
pg_stat_statements view were last reset.
Per discussion, this commit also changes pg_stat_statements_info code
so that "dealloc" column is reset at the same time as "stats_reset" is reset,
i.e., whenever all pg_stat_statements entries are removed, for the sake
of consistency. Previously "dealloc" was reset only when
pg_stat_statements_reset(0, 0, 0) is called and was not reset when
pg_stat_statements_reset() with non-zero value argument discards all
entries. This was confusing.
Author: Naoki Nakamichi, Yuki Seino
Reviewed-by: Yuki Seino, Kyotaro Horiguchi, Li Japin, Fujii Masao
Discussion: https://postgr.es/m/c102cf3180d0ee73c1c5a0f7f8558322@oss.nttdata.com
Invent a new flag bit HASH_STRINGS to specify C-string hashing, which
was formerly the default; and add assertions insisting that exactly
one of the bits HASH_STRINGS, HASH_BLOBS, and HASH_FUNCTION be set.
This is in hopes of preventing recurrences of the type of oversight
fixed in commit a1b8aa1e4 (i.e., mistakenly omitting HASH_BLOBS).
Also, when HASH_STRINGS is specified, insist that the keysize be
more than 8 bytes. This is a heuristic, but it should catch
accidental use of HASH_STRINGS for integer or pointer keys.
(Nearly all existing use-cases set the keysize to NAMEDATALEN or
more, so there's little reason to think this restriction should
be problematic.)
Tweak hash_create() to insist that the HASH_ELEM flag be set, and
remove the defaults it had for keysize and entrysize. Since those
defaults were undocumented and basically useless, no callers
omitted HASH_ELEM anyway.
Also, remove memset's zeroing the HASHCTL parameter struct from
those callers that had one. This has never been really necessary,
and while it wasn't a bad coding convention it was confusing that
some callers did it and some did not. We might as well save a few
cycles by standardizing on "not".
Also improve the documentation for hash_create().
In passing, improve reinit.c's usage of a hash table by storing
the key as a binary Oid rather than a string; and, since that's
a temporary hash table, allocate it in CurrentMemoryContext for
neatness.
Discussion: https://postgr.es/m/590625.1607878171@sss.pgh.pa.us
This adjusts some code related to recent changes for cryptohash
functions:
- Add a variable in md5.h to track down the size of a computed result,
moved from pgcrypto. Note that pg_md5_hash() assumed a result of this
size already.
- Call explicit_bzero() on the hashed data when freeing the context for
fallback implementations. For MD5, particularly, it would be annoying
to leave some non-zeroed data around.
- Clean up some code related to recent changes of uuid-ossp. .gitignore
still included md5.c and a comment was incorrect.
Discussion: https://postgr.es/m/X9HXKTgrvJvYO7Oh@paquier.xyz
This is basically a finger exercise to prove that it's possible for
an extension module to add subscripting ability. Subscripted fetch
from an hstore is not different from the existing "hstore -> text"
operator. Subscripted update does seem to be a little easier to
use than the traditional update method using hstore concatenation,
but it's not a fundamentally new ability.
However, there may be some value in the code as sample code, since
it shows what's basically the minimum-complexity way to implement
subscripting when one needn't consider nested container objects.
Discussion: https://postgr.es/m/3724341.1607551174@sss.pgh.pa.us
This module had a dependency on pgcrypto's md5.c that got removed by
b67b57a. Instead of the code from pgcrypto, this code can just use the
new cryptohash routines for MD5 as a drop-in replacement, so let's just
do this switch. This has also the merit to simplify a bit the
compilation of uuid-ossp.
This requires --with-uuid to be reproduced, and I have used e2fs as a
way to reproduce the failure, then test this commit.
Per reports from buildfarm members longfin, florican and sifaka.
Discussion: https://postgr.es/m/X9GToVd3QmWeNvj8@paquier.xyz
This commit heavily reorganizes the MD5 implementations that exist in
the tree in various aspects.
First, MD5 is added to the list of options available in cryptohash.c and
cryptohash_openssl.c. This means that if building with OpenSSL, EVP is
used for MD5 instead of the fallback implementation that Postgres had
for ages. With the recent refactoring work for cryptohash functions,
this change is straight-forward. If not building with OpenSSL, a
fallback implementation internal to src/common/ is used.
Second, this reduces the number of MD5 implementations present in the
tree from two to one, by moving the KAME implementation from pgcrypto to
src/common/, and by removing the implementation that existed in
src/common/. KAME was already structured with an init/update/final set
of routines by pgcrypto (see original pgcrypto/md5.h) for compatibility
with OpenSSL, so moving it to src/common/ has proved to be a
straight-forward move, requiring no actual manipulation of the internals
of each routine. Some benchmarking has not shown any performance gap
between both implementations.
Similarly to the fallback implementation used for SHA2, the fallback
implementation of MD5 is moved to src/common/md5.c with an internal
header called md5_int.h for the init, update and final routines. This
gets then consumed by cryptohash.c.
The original routines used for MD5-hashed passwords are moved to a
separate file called md5_common.c, also in src/common/, aimed at being
shared between all MD5 implementations as utility routines to keep
compatibility with any code relying on them.
Like the SHA2 changes, this commit had its round of tests on both Linux
and Windows, across all versions of OpenSSL supported on HEAD, with and
even without OpenSSL.
Author: Michael Paquier
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/20201106073434.GA4961@paquier.xyz
This patch generalizes the subscripting infrastructure so that any
data type can be subscripted, if it provides a handler function to
define what that means. Traditional variable-length (varlena) arrays
all use array_subscript_handler(), while the existing fixed-length
types that support subscripting use raw_array_subscript_handler().
It's expected that other types that want to use subscripting notation
will define their own handlers. (This patch provides no such new
features, though; it only lays the foundation for them.)
To do this, move the parser's semantic processing of subscripts
(including coercion to whatever data type is required) into a
method callback supplied by the handler. On the execution side,
replace the ExecEvalSubscriptingRef* layer of functions with direct
calls to callback-supplied execution routines. (Thus, essentially
no new run-time overhead should be caused by this patch. Indeed,
there is room to remove some overhead by supplying specialized
execution routines. This patch does a little bit in that line,
but more could be done.)
Additional work is required here and there to remove formerly
hard-wired assumptions about the result type, collation, etc
of a SubscriptingRef expression node; and to remove assumptions
that the subscript values must be integers.
One useful side-effect of this is that we now have a less squishy
mechanism for identifying whether a data type is a "true" array:
instead of wiring in weird rules about typlen, we can look to see
if pg_type.typsubscript == F_ARRAY_SUBSCRIPT_HANDLER. For this
to be bulletproof, we have to forbid user-defined types from using
that handler directly; but there seems no good reason for them to
do so.
This patch also removes assumptions that the number of subscripts
is limited to MAXDIM (6), or indeed has any hard-wired limit.
That limit still applies to types handled by array_subscript_handler
or raw_array_subscript_handler, but to discourage other dependencies
on this constant, I've moved it from c.h to utils/array.h.
Dmitry Dolgov, reviewed at various times by Tom Lane, Arthur Zakirov,
Peter Eisentraut, Pavel Stehule
Discussion: https://postgr.es/m/CA+q6zcVDuGBv=M0FqBYX8DPebS3F_0KQ6OVFobGJPM507_SZ_w@mail.gmail.com
Discussion: https://postgr.es/m/CA+q6zcVovR+XY4mfk-7oNk-rF91gH0PebnNfuUjuuDsyHjOcVA@mail.gmail.com
The following routines are called within pgcrypto when handling digests
but there were no checks for failures:
- EVP_MD_CTX_size (can fail with -1 as of 3.0.0)
- EVP_MD_CTX_block_size (can fail with -1 as of 3.0.0)
- EVP_DigestInit_ex
- EVP_DigestUpdate
- EVP_DigestFinal_ex
A set of elog(ERROR) is added by this commit to detect such failures,
that should never happen except in the event of a processing failure
internal to OpenSSL.
Note that it would be possible to use ERR_reason_error_string() to get
more context about such errors, but these refer mainly to the internals
of OpenSSL, so it is not really obvious how useful that would be. This
is left out for simplicity.
Per report from Coverity. Thanks to Tom Lane for the discussion.
Backpatch-through: 9.5
Two new routines to allocate a hash context and to free it are created,
as these become necessary for the goal behind this refactoring: switch
the all cryptohash implementations for OpenSSL to use EVP (for FIPS and
also because upstream does not recommend the use of low-level cryptohash
functions for 20 years). Note that OpenSSL hides the internals of
cryptohash contexts since 1.1.0, so it is necessary to leave the
allocation to OpenSSL itself, explaining the need for those two new
routines. This part is going to require more work to properly track
hash contexts with resource owners, but this not introduced here.
Still, this refactoring makes the move possible.
This reduces the number of routines for all SHA2 implementations from
twelve (SHA{224,256,386,512} with init, update and final calls) to five
(create, free, init, update and final calls) by incorporating the hash
type directly into the hash context data.
The new cryptohash routines are moved to a new file, called cryptohash.c
for the fallback implementations, with SHA2 specifics becoming a part
internal to src/common/. OpenSSL specifics are part of
cryptohash_openssl.c. This infrastructure is usable for more hash
types, like MD5 or HMAC.
Any code paths using the internal SHA2 routines are adapted to report
correctly errors, which are most of the changes of this commit. The
zones mostly impacted are checksum manifests, libpq and SCRAM.
Note that e21cbb4 was a first attempt to switch SHA2 to EVP, but it
lacked the refactoring needed for libpq, as done here.
This patch has been tested on Linux and Windows, with and without
OpenSSL, and down to 1.0.1, the oldest version supported on HEAD.
Author: Michael Paquier
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/20200924025314.GE7405@paquier.xyz
If more distinct statements than pg_stat_statements.max are observed,
pg_stat_statements entries about the least-executed statements are
deallocated. This commit enables us to track the total number of times
those entries were deallocated. That number can be viewed in the
pg_stat_statements_info view that this commit adds. It's useful when
tuning pg_stat_statements.max parameter. If it's high, i.e., the entries
are deallocated very frequently, which might cause the performance
regression and we can increase pg_stat_statements.max to avoid those
frequent deallocations.
The pg_stat_statements_info view is intended to display the statistics
of pg_stat_statements module itself. Currently it has only one column
"dealloc" indicating the number of times entries were deallocated.
But an upcoming patch will add other columns (for example, the time
at which pg_stat_statements statistics were last reset) into the view.
Author: Katsuragi Yuta, Yuki Seino
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/0d9f1107772cf5c3f954e985464c7298@oss.nttdata.com
The function converted the first argument i.e. the number of tuples to
return into an unsigned integer which turns out to be huge number when
a negative value is passed. This causes the function to take much
longer time to execute. Instead, reject a negative value.
(If someone really wants to generate many more result rows, they
should consider adding a bigint or numeric variant.)
While at it, improve SQL test to test the number of tuples returned by
this function.
Author: Ashutosh Bapat <ashutosh.bapat@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/CAG-ACPW3PUUmSnM6cLa9Rw4BEC5cEMKjX8Gogc8gvQcT3cYA1A@mail.gmail.com
Commit 0a2bc5d61e changed the order that permissions on the final and
transition functions of an aggregate are checked in. That shows up as a
difference in the order the LOG messages in this sepgsql regression test
are printed. Adjust the expected output.
Per buildfarm failure in rhinoceros.
Copy.c has grown really large. Split it into more manageable parts:
- copy.c now contains only a few functions that are common to COPY FROM
and COPY TO.
- copyto.c contains code for COPY TO.
- copyfrom.c contains code for initializing COPY FROM, and inserting the
tuples to the correct table.
- copyfromparse.c contains code for reading from the client/file/program,
and parsing the input text/CSV/binary format into tuples.
All of these parts are fairly complicated, and fairly independent of each
other. There is a patch being discussed to implement parallel COPY FROM,
which will add a lot of new code to the COPY FROM path, and another patch
which would allow INSERTs to use the same multi-insert machinery as COPY
FROM, both of which will require refactoring that code. With those two
patches, there's going to be a lot of code churn in copy.c anyway, so now
seems like a good time to do this refactoring.
The CopyStateData struct is also split. All the formatting options, like
FORMAT, QUOTE, ESCAPE, are put in a new CopyFormatOption struct, which
is used by both COPY FROM and TO. Other state data are kept in separate
CopyFromStateData and CopyToStateData structs.
Reviewed-by: Soumyadeep Chakraborty, Erik Rijkers, Vignesh C, Andres Freund
Discussion: https://www.postgresql.org/message-id/8e15b560-f387-7acc-ac90-763986617bfb%40iki.fi
In streaming mode, the transaction can be decoded in multiple streams and
those streams can be interleaved with streams of other transactions. So,
we can't remember the transaction's write status in the logical decoding
context because that might get changed due to some other transactions and
lead to wrong answers for 'skip-empty-xacts' option. We decided to keep
each transaction's write status in the ReorderBufferTxn to avoid
interleaved streams changing the status of some unrelated transactions.
Diagnosed-by: Amit Kapila
Author: Dilip Kumar
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CAA4eK1LR7=XNM_TLmpZMFuV8ZQpoxkem--NZJYf8YXmesbvwLA@mail.gmail.com
Obviously, in order to equality operator be satisfiable, target string must
contain all the trigrams of the search string. On this base, we implement
equality operator in GiST/GIN indexes with recheck.
Discussion: https://postgr.es/m/CAOBaU_YWwtT7tdggtROacjdOdeYHCz-tmSwuC-j-TOG-g97J0w%40mail.gmail.com
Author: Julien Rouhaud
Reviewed-by: Tom Lane, Alexander Korotkov, Georgios Kokolatos, Erik Rijkers
Whether from size overflow in gistSplit or from secondary splits,
picksplit is (rarely) called with exactly two items to split.
Formerly, due to special-case handling of the last item, this would
lead to access to an uninitialized cache entry; prior to PG 13 this
might have been harmless or at worst led to an incorrect union datum,
but in 13 onwards it can cause a backend crash from using an
uninitialized pointer.
Repair by removing the special case, which was deemed not to have been
appropriate anyway. Backpatch all the way, because this bug has
existed since pg_trgm was added.
Per report on IRC from user "ftzdomino". Analysis and testing by me,
patch from Alexander Korotkov.
Discussion: https://postgr.es/m/87k0usfdxg.fsf@news-spur.riddles.org.uk
911e702077 has introduced the opclass parameters including signature length
for a set of GiST opclasses. Due to copy-pasting, macro for getting the
signature length in trgm_gist.c was named LTREE_GET_ASIGLEN(). Fix that by
renaming this macro to just GET_SIGLEN().
Backpatch-through: 13
Commit 6023b7ea71 allowed pg_stat_statements to track the number
of rows retrieved or affected by some utility commands including
CREATE MATERIALIZED VIEW. However it did not track the rowcount
of REFRESH MATERIALIZED VIEW. This commit allows pg_stat_statements
to track that.
To track that, this commit changes the query completion for
REFRESH MATERIALIZED VIEW so that it saves the rowcount. But note that
the rowcount is still not displayed in the command completion tag output.
That is, the display_rowcount flag of CMDTAG_REFRESH_MATERIALIZED_VIEW
command tag is left false in cmdtaglist.h. Otherwise, the change of
completion tag output might break applications using it.
Author: Katsuragi Yuta, Seino Yuki
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/71f6bc72f8bbaa06e701f8bd2562c347@oss.nttdata.com
Discussion: https://postgr.es/m/aadbfba9-e4bb-9531-6b3a-d13c31c8f4fe@oss.nttdata.com
Introduce TimestampDifferenceMilliseconds() to simplify callers
that would rather have the difference in milliseconds, instead of
the select()-oriented seconds-and-microseconds format. This gets
rid of at least one integer division per call, and it eliminates
some apparently-easy-to-mess-up arithmetic.
Two of these call sites were in fact wrong:
* pg_prewarm's autoprewarm_main() forgot to multiply the seconds
by 1000, thus ending up with a delay 1000X shorter than intended.
That doesn't quite make it a busy-wait, but close.
* postgres_fdw's pgfdw_get_cleanup_result() thought it needed to compute
microseconds not milliseconds, thus ending up with a delay 1000X longer
than intended. Somebody along the way had noticed this problem but
misdiagnosed the cause, and imposed an ad-hoc 60-second limit rather
than fixing the units. This was relatively harmless in context, because
we don't care that much about exactly how long this delay is; still,
it's wrong.
There are a few more callers of TimestampDifference() that don't
have a direct need for seconds-and-microseconds, but can't use
TimestampDifferenceMilliseconds() either because they do need
microsecond precision or because they might possibly deal with
intervals long enough to overflow 32-bit milliseconds. It might be
worth inventing another API to improve that, but that seems outside
the scope of this patch; so those callers are untouched here.
Given the fact that we are fixing some bugs, and the likelihood
that future patches might want to back-patch code that uses this
new API, back-patch to all supported branches.
Alexey Kondratov and Tom Lane
Discussion: https://postgr.es/m/3b1c053a21c07c1ed5e00be3b2b855ef@postgrespro.ru
Specifically, this blocks DECLARE ... WITH HOLD and firing of deferred
triggers within index expressions and materialized view queries. An
attacker having permission to create non-temp objects in at least one
schema could execute arbitrary SQL functions under the identity of the
bootstrap superuser. One can work around the vulnerability by disabling
autovacuum and not manually running ANALYZE, CLUSTER, REINDEX, CREATE
INDEX, VACUUM FULL, or REFRESH MATERIALIZED VIEW. (Don't restore from
pg_dump, since it runs some of those commands.) Plain VACUUM (without
FULL) is safe, and all commands are fine when a trusted user owns the
target object. Performance may degrade quickly under this workaround,
however. Back-patch to 9.5 (all supported versions).
Reviewed by Robert Haas. Reported by Etienne Stalmans.
Security: CVE-2020-25695
Move the system catalog index declarations from catalog/indexing.h to
the respective parent tables' catalog/pg_*.h files. The original
reason for having it split was that the old genbki system produced the
output in the order of the catalog files it read, so all the indexing
stuff needed to come separately. But this is no longer the case, and
keeping it together makes more sense.
Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/c7cc82d6-f976-75d6-2e3e-b03d2cab26bb@2ndquadrant.com
sslinfo was passing the Port->ssl member directly to OpenSSL in order
to extract information regarding the connection. This breaks the API
provided by the backend TLS implementation, as well as duplicates code
for no benefit. Rewrite to make use of the backend API as much as
possible.
Author: Daniel Gustafsson <daniel@yesql.se>
PXE_DECRYPT_FAILED exists already for decryption errors, and an
equivalent for encryption did not exist. There is one code path that
deals with such failures for OpenSSL but it used PXE_ERR_GENERIC, which
was inconsistent. This switches this code path to use the new error
PXE_ENCRYPT_FAILED instead of PXE_ERR_GENERIC, making the code used for
encryption more consistent with the decryption.
Author: Daniel Gustafsson
Discussion: https://postgr.es/m/03049139-CB7A-436E-B71B-42696D3E2EF7@yesql.se
verify_heapam() wasn't being careful to sanity-check tuple line
pointers before using them, resulting in SIGBUS on alignment-picky
architectures. Fix that, add some more test coverage.
Mark Dilger, some tweaking by me
Discussion: https://postgr.es/m/30B8E99A-2D9C-48D4-A55C-741C9D5F1563@enterprisedb.com
Change the attribute 'name' to 'slot_name' in pg_stat_replication_slots
view to make it clear and that way we will be consistent with the other
places like pg_stat_wal_receiver view where we display the same attribute.
In the passing, fix the typo in one of the macros in the related code.
Bump the catversion as we have modified the name in the catalog as well.
Reported-by: Noriyoshi Shinoda
Author: Noriyoshi Shinoda
Reviewed-by: Sawada Masahiko and Amit Kapila
Discussion: https://postgr.es/m/CA+fd4k5_pPAYRTDrO2PbtTOe0eHQpBvuqmCr8ic39uTNmR49Eg@mail.gmail.com
When allocating a EVP context, it would have been possible to leak some
memory allocated directly by OpenSSL, that PostgreSQL lost track of if
the initialization of the context allocated failed. The cleanup can be
done with EVP_MD_CTX_destroy().
Note that EVP APIs exist since OpenSSL 0.9.7 and we have in the tree
equivalent implementations for older versions since ce9b75d (code
removed with 9b7cd59a as of 10~). However, in 9.5 and 9.6, the existing
code makes use of EVP_MD_CTX_destroy() and EVP_MD_CTX_create() without
an equivalent implementation when building the tree with OpenSSL 0.9.6
or older, meaning that this code is in reality broken with such versions
since it got introduced in e2838c5. As we have heard no complains about
that, it does not seem worth bothering with in 9.5 and 9.6, so I have
left that out for simplicity.
Author: Michael Paquier
Discussion: https://postgr.es/m/20201015072212.GC2305@paquier.xyz
Backpatch-through: 9.5
In theory, the second px_find_digest call in px_crypt_md5 could fail
even though the first one succeeded, since resource allocation is
required. Don't skip testing for a failure. (If one did happen,
the likely result would be a crash rather than clean recovery from
an OOM failure.)
The code's been like this all along, so back-patch to all supported
branches.
Daniel Gustafsson
Discussion: https://postgr.es/m/AA8D6FE9-4AB2-41B4-98CB-AE64BA668C03@yesql.se
Commit 32a9c0bdf introduced connection retry logic into postgres_fdw.
Previously it used goto statement for retry. This commit gets rid of that
goto from the logic to make the code simpler and easier-to-read.
When getting out of PG_CATCH() for the retry, the error state should be
cleaned up and the memory context should be reset. But commit 32a9c0bdf
forgot to do that. This commit also fixes this bug.
Previously only PQstatus()==CONNECTION_BAD was verified to detect
connection failure. But this could cause false detection in the case where
any error other than connection failure (e.g., out-of-memory) was thrown
after a broken connection was detected in libpq and CONNECTION_BAD is set.
To fix this issue, this commit changes the logic so that it also checks
the error's sqlstate is ERRCODE_CONNECTION_FAILURE.
Author: Fujii Masao
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/2943611.1602375376@sss.pgh.pa.us
A number of places were using appendStringInfo() when they could have been
using appendStringInfoString() instead. While there's no functionality
change there, it's just more efficient to use appendStringInfoString()
when no formatting is required. Likewise for some
appendStringInfoString() calls which were just appending a single char.
We can just use appendStringInfoChar() for that.
Additionally, many places were using appendPQExpBuffer() when they could
have used appendPQExpBufferStr(). Change those too.
Patch by Zhijie Hou, but further searching by me found significantly more
places that deserved the same treatment.
Author: Zhijie Hou, David Rowley
Discussion: https://postgr.es/m/cb172cf4361e4c7ba7167429070979d4@G08CNEXMBPEKD05.g08.fujitsu.local
FDWs that can perform an UPDATE/DELETE remotely using the "direct modify"
set of APIs need to access the ResultRelInfo of the target table. That's
currently available in EState.es_result_relation_info, but the next
commit will remove that field.
This commit adds a new resultRelation field in ForeignScan, to store the
target relation's RT index, and the corresponding ResultRelInfo in
ForeignScanState. The FDW's PlanDirectModify callback is expected to set
'resultRelation' along with 'operation'. The core code doesn't need them
for anything, they are for the convenience of FDW's Begin- and
IterateDirectModify callbacks.
Authors: Amit Langote, Etsuro Fujita
Discussion: https://www.postgresql.org/message-id/CA%2BHiwqGEmiib8FLiHMhKB%2BCH5dRgHSLc5N5wnvc4kym%2BZYpQEQ%40mail.gmail.com
The test cases added by that commit were trying to test the exact number of
times a particular transaction has spilled. However, that number can vary if
any background transaction (say by autovacuum) happens in parallel to the main
transaction. So let's not try to verify the exact count.
Author: Amit Kapila
Reviewed-by: Sawada Masahiko
Discussion: https://postgr.es/m/CA+fd4k5_pPAYRTDrO2PbtTOe0eHQpBvuqmCr8ic39uTNmR49Eg@mail.gmail.com
Buildfarm member lorikeet is still failing the test from commit
32a9c0bdf, but now it's down to the should-have-foreseen-it problem
that the error message isn't what the expected-output file expects.
Let's see if we can get stable results by printing just the SQLSTATE.
I believe we'll reliably see ERRCODE_CONNECTION_FAILURE, since
pgfdw_report_error() will report that for any libpq-originated error.
There may be a better way to do this, but I'd like to get the
buildfarm back to green before we discuss further improvements.
Discussion: https://postgr.es/m/E1kPc9v-0005L4-2l@gemulon.postgresql.org
Discussion: https://postgr.es/m/2621622.1602184554@sss.pgh.pa.us
In postgres_fdw, once remote connections are established, they are cached
and re-used for subsequent queries and transactions. There can be some
cases where those cached connections are unavaiable, for example,
by the restart of remote server. In these cases, previously an error was
reported and the query accessing to remote server failed if new remote
transaction failed to start because the cached connection was broken.
This commit improves postgres_fdw so that new connection is remade
if broken connection is detected when starting new remote transaction.
This is useful to avoid unnecessary failure of queries when connection is
broken but can be reestablished.
Author: Bharath Rupireddy, tweaked a bit by Fujii Masao
Reviewed-by: Ashutosh Bapat, Tatsuhito Kasahara, Fujii Masao
Discussion: https://postgr.es/m/CALj2ACUAi23vf1WiHNar_LksM9EDOWXcbHCo-fD4Mbr1d=78YQ@mail.gmail.com
PX_OWN_ALLOC was intended as a way to disable the use of palloc(), and
over the time new palloc() or equivalent calls have been added like in
32984d8, making this extra layer losing its original purpose. This
simplifies on the way some code paths to use palloc0() rather than
palloc() followed by memset(0).
Author: Daniel Gustafsson
Discussion: https://postgr.es/m/A5BFAA1A-B2E8-4CBC-895E-7B1B9475A527@yesql.se
You can use this to view the contents of the time to XID mapping
which the server maintains when old_snapshot_threshold != -1.
Being able to view that information may be interesting for users,
and it's definitely useful for figuring out whether the mapping
is being maintained correctly. It isn't, so that will need to be
fixed in a subsequent commit.
Patch by me, reviewed by Thomas Munro, Dilip Kumar, Hamid Akhtar.
Discussion: http://postgr.es/m/CA+TgmoY=aqf0zjTD+3dUWYkgMiNDegDLFjo+6ze=Wtpik+3XqA@mail.gmail.com
According to buildfarm member sungazer, the behavior of VACUUM can be
unstable in these tests even if we prevent autovacuum from running on
the tables in question, apparently because even a manual vacuum can
behave differently depending on whether anything else is running that
holds back the global xmin. So use a temporary table instead, which
as of commit a7212be8b9 enables
vacuuming using a more aggressive cutoff.
This approach can't be used for the regression test that involves a
materialized view, but that test doesn't run vacuum, so it shouldn't
be prone to this particular failure mode.
Analysis by Tom Lane. Patch by Ashutosh Sharma and me.
Discussion: http://postgr.es/m/665524.1599948007@sss.pgh.pa.us
This feature has been a thorn in our sides for a long time, causing
many grammatical ambiguity problems. It doesn't seem worth the
pain to continue to support it, so remove it.
There are some follow-on improvements we can make in the grammar,
but this commit only removes the bare minimum number of productions,
plus assorted backend support code.
Note that pg_dump and psql continue to have full support, since
they may be used against older servers. However, pg_dump warns
about postfix operators. There is also a check in pg_upgrade.
Documentation-wise, I (tgl) largely removed the "left unary"
terminology in favor of saying "prefix operator", which is
a more standard and IMO less confusing term.
I included a catversion bump, although no initial catalog data
changes here, to mark the boundary at which oprkind = 'r'
stopped being valid in pg_operator.
Mark Dilger, based on work by myself and Robert Haas;
review by John Naylor
Discussion: https://postgr.es/m/38ca86db-42ab-9b48-2902-337a0d6b8311@2ndquadrant.com
The "!" operator is our only built-in postfix operator. Remove it,
on the way to removal of grammar support for postfix operators.
There is also a "!!" prefix operator, but since it's been marked
deprecated for most of its existence, we might as well remove it too.
Also zap the SQL alias function numeric_fac(), which seems to have
equally little reason to live.
Mark Dilger, based on work by myself and Robert Haas;
review by John Naylor
Discussion: https://postgr.es/m/38ca86db-42ab-9b48-2902-337a0d6b8311@2ndquadrant.com
Commit d114cc53 overlooked the fact that pg_upgrade'd B-Tree indexes
have leaf page high keys whose offset numbers do not match the one from
the copy of the tuple one level up (the copy stored with a downlink for
leaf page's right sibling page). This led to false positive reports of
corruption from bt_index_parent_check() when it was called to verify a
pg_upgrade'd index.
To fix, skip comparing the offset number on pg_upgrade'd B-Tree indexes.
Author: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>
Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Andrew Bille <andrewbille@gmail.com>
Diagnosed-By: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>
Bug: #16619
Discussion: https://postgr.es/m/16619-aaba10f83fdc1c3c@postgresql.org
Backpatch: 13-, where child check was enhanced.
We were decoding empty transactions via streaming APIs added in commit
45fdc9738b even when the user used the option 'skip-empty-xacts'. The APIs
makes no effort to skip empty xacts under the assumption that we will
never try to stream such transactions. However, that is not true because
we can pick to stream a transaction that has change messages for
REORDER_BUFFER_CHANGE_INTERNAL_SNAPSHOT and we don't send such messages to
downstream rather they are just to update the internal state. So, we need
to skip such xacts when plugin uses the option 'skip-empty-xacts'.
Diagnosed-By: Amit Kapila
Author: Dilip Kumar
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CAA4eK1+OqgFNZkf7=ETe_y5ntjgDk3T0wcdkd4Sot_u1hySGfw@mail.gmail.com
Sometimes it happens that the visibility information for a tuple
becomes corrupted, either due to bugs in the database software or
external factors. Provide a function heap_force_kill() that can
be used to truncate such dead tuples to dead line pointers, and
a function heap_force_freeze() that can be used to overwrite the
visibility information in such a way that the tuple becomes
all-visible.
These functions are unsafe, in that you can easily use them to
corrupt a database that was not previously corrupted, and you can
use them to further corrupt an already-corrupted database or to
destroy data. The documentation accordingly cautions against
casual use. However, in some cases they permit recovery of data
that would otherwise be very difficult to recover, or to allow a
system to continue to function when it would otherwise be difficult
to do so.
Because we may want to add other functions for performing other
kinds of surgery in the future, the new contrib module is called
pg_surgery rather than something specific to these functions. I
proposed back-patching this so that it could be more easily used
by people running existing releases who are facing these kinds of
problems, but that proposal did not attract enough support, so
no back-patch for now.
Ashutosh Sharma, reviewed and tested by Andrey M. Borodin,
M. Beena Emerson, Masahiko Sawada, Rajkumar Raghuwanshi,
Asim Praveen, and Mark Dilger, and somewhat revised by me.
Discussion: http://postgr.es/m/CA+TgmoZW1fsU-QUNCRUQMGUygBDPVeOTLCqRdQZch=EYZnctSA@mail.gmail.com
Until now, REINDEX was not able to work with partitioned tables and
indexes, forcing users to reindex partitions one by one. This extends
REINDEX INDEX and REINDEX TABLE so as they can accept a partitioned
index and table in input, respectively, to reindex all the partitions
assigned to them with physical storage (foreign tables, partitioned
tables and indexes are then discarded).
This shares some logic with schema and database REINDEX as each
partition gets processed in its own transaction after building a list of
relations to work on. This choice has the advantage to minimize the
number of invalid indexes to one partition with REINDEX CONCURRENTLY in
the event a cancellation or failure in-flight, as the only indexes
handled at once in a single REINDEX CONCURRENTLY loop are the ones from
the partition being working on.
Isolation tests are added to emulate some cases I bumped into while
developing this feature, particularly with the concurrent drop of a
leaf partition reindexed. However, this is rather limited as LOCK would
cause REINDEX to block in the first transaction building the list of
partitions.
Per its multi-transaction nature, this new flavor cannot run in a
transaction block, similarly to REINDEX SCHEMA, SYSTEM and DATABASE.
Author: Justin Pryzby, Michael Paquier
Reviewed-by: Anastasia Lubennikova
Discussion: https://postgr.es/m/db12e897-73ff-467e-94cb-4af03705435f.adger.lj@alibaba-inc.com
This patch started out with the goal of harmonizing various arbitrary
limits on password length, but after awhile a better idea emerged:
let's just get rid of those fixed limits.
recv_password_packet() has an arbitrary limit on the packet size,
which we don't really need, so just drop it. (Note that this doesn't
really affect anything for MD5 or SCRAM password verification, since
those will hash the user's password to something shorter anyway.
It does matter for auth methods that require a cleartext password.)
Likewise remove the arbitrary error condition in pg_saslprep().
The remaining limits are mostly in client-side code that prompts
for passwords. To improve those, refactor simple_prompt() so that
it allocates its own result buffer that can be made as big as
necessary. Actually, it proves best to make a separate routine
pg_get_line() that has essentially the semantics of fgets(), except
that it allocates a suitable result buffer and hence will never
return a truncated line. (pg_get_line has a lot of potential
applications to replace randomly-sized fgets buffers elsewhere,
but I'll leave that for another patch.)
I built pg_get_line() atop stringinfo.c, which requires moving
that code to src/common/; but that seems fine since it was a poor
fit for src/port/ anyway.
This patch is mostly mine, but it owes a good deal to Nathan Bossart
who pressed for a solution to the password length problem and
created a predecessor patch. Also thanks to Peter Eisentraut and
Stephen Frost for ideas and discussion.
Discussion: https://postgr.es/m/09512C4F-8CB9-4021-B455-EF4C4F0D55A0@amazon.com
Historically, we've considered the state with relpages and reltuples
both zero as indicating that we do not know the table's tuple density.
This is problematic because it's impossible to distinguish "never yet
vacuumed" from "vacuumed and seen to be empty". In particular, a user
cannot use VACUUM or ANALYZE to override the planner's normal heuristic
that an empty table should not be believed to be empty because it is
probably about to get populated. That heuristic is a good safety
measure, so I don't care to abandon it, but there should be a way to
override it if the table is indeed intended to stay empty.
Hence, represent the initial state of ignorance by setting reltuples
to -1 (relpages is still set to zero), and apply the minimum-ten-pages
heuristic only when reltuples is still -1. If the table is empty,
VACUUM or ANALYZE (but not CREATE INDEX) will override that to
reltuples = relpages = 0, and then we'll plan on that basis.
This requires a bunch of fiddly little changes, but we can get rid of
some ugly kluges that were formerly needed to maintain the old definition.
One notable point is that FDWs' GetForeignRelSize methods will see
baserel->tuples = -1 when no ANALYZE has been done on the foreign table.
That seems like a net improvement, since those methods were formerly
also in the dark about what baserel->tuples = 0 really meant. Still,
it is an API change.
I bumped catversion because code predating this change would get confused
by seeing reltuples = -1.
Discussion: https://postgr.es/m/F02298E0-6EF4-49A1-BCB6-C484794D9ACC@thebuild.com
When calling cracklib to check the password, the diagnostic from
cracklib was thrown away. This would hide essential information such
as no dictionary being installed. Change this to show the cracklib
error message using errdetail_log().
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://www.postgresql.org/message-id/flat/f7266133-618a-0adc-52ef-f43c78806b0e%402ndquadrant.com
REPLICA IDENTITY USING INDEX behaves the same way as NOTHING if the
associated index is dropped, even if there is a primary key that could
be used as a fallback for the changes generated. There have never been
any tests to cover such scenarios, so this commit closes the gap.
Author: Michael Paquier
Reviewed-by: Masahiko Sawada, Rahila Syed, Euler Taveira
Discussion: https://postgr.es/m/20200522035028.GO2355@paquier.xyz
xact.h included utils/datetime.h, which cannot be used in the frontend
(it includes fmgr.h, which needs Datum). But xact.h only needs the
definition of TimestampTz from it, which is available directly in
datatypes/timestamp.h. Change xact.h to include that instead of
utils/datetime.h, so that it can be used in client programs.
Since commit 865f14a2d made "=>" unusable as an operator name,
it's been impossible either to install hstore 1.0 or to execute
this update script. There's not much point in continuing
to ship it.
Discussion: https://postgr.es/m/653936.1597431032@sss.pgh.pa.us
Upstream SELinux has recently marked security_context_t as officially
deprecated, causing warnings with -Wdeprecated-declarations. This is
considered as legacy code for some time now by upstream as
security_context_t got removed from most of the code tree during the
development of 2.3 back in 2014.
This removes all the references to security_context_t in sepgsql/ to be
consistent with SELinux, fixing the warnings. Note that this does not
impact the minimum version of libselinux supported.
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20200813012735.GC11663@paquier.xyz
To make GetSnapshotData() more scalable, it cannot not look at at each proc's
xmin: While snapshot contents do not need to change whenever a read-only
transaction commits or a snapshot is released, a proc's xmin is modified in
those cases. The frequency of xmin modifications leads to, particularly on
higher core count systems, many cache misses inside GetSnapshotData(), despite
the data underlying a snapshot not changing. That is the most
significant source of GetSnapshotData() scaling poorly on larger systems.
Without accessing xmins, GetSnapshotData() cannot calculate accurate horizons /
thresholds as it has so far. But we don't really have to: The horizons don't
actually change that much between GetSnapshotData() calls. Nor are the horizons
actually used every time a snapshot is built.
The trick this commit introduces is to delay computation of accurate horizons
until there use and using horizon boundaries to determine whether accurate
horizons need to be computed.
The use of RecentGlobal[Data]Xmin to decide whether a row version could be
removed has been replaces with new GlobalVisTest* functions. These use two
thresholds to determine whether a row can be pruned:
1) definitely_needed, indicating that rows deleted by XIDs >= definitely_needed
are definitely still visible.
2) maybe_needed, indicating that rows deleted by XIDs < maybe_needed can
definitely be removed
GetSnapshotData() updates definitely_needed to be the xmin of the computed
snapshot.
When testing whether a row can be removed (with GlobalVisTestIsRemovableXid())
and the tested XID falls in between the two (i.e. XID >= maybe_needed && XID <
definitely_needed) the boundaries can be recomputed to be more accurate. As it
is not cheap to compute accurate boundaries, we limit the number of times that
happens in short succession. As the boundaries used by
GlobalVisTestIsRemovableXid() are never reset (with maybe_needed updated by
GetSnapshotData()), it is likely that further test can benefit from an earlier
computation of accurate horizons.
To avoid regressing performance when old_snapshot_threshold is set (as that
requires an accurate horizon to be computed), heap_page_prune_opt() doesn't
unconditionally call TransactionIdLimitedForOldSnapshots() anymore. Both the
computation of the limited horizon, and the triggering of errors (with
SetOldSnapshotThresholdTimestamp()) is now only done when necessary to remove
tuples.
This commit just removes the accesses to PGXACT->xmin from
GetSnapshotData(), but other members of PGXACT residing in the same
cache line are accessed. Therefore this in itself does not result in a
significant improvement. Subsequent commits will take advantage of the
fact that GetSnapshotData() now does not need to access xmins anymore.
Note: This contains a workaround in heap_page_prune_opt() to keep the
snapshot_too_old tests working. While that workaround is ugly, the tests
currently are not meaningful, and it seems best to address them separately.
Author: Andres Freund <andres@anarazel.de>
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Reviewed-By: Thomas Munro <thomas.munro@gmail.com>
Reviewed-By: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/20200301083601.ews6hz5dduc3w2se@alap3.anarazel.de
They are equivalent, except that StrNCpy() zero-fills the entire
destination buffer instead of providing just one trailing zero. For
all but a tiny number of callers, that's just overhead rather than
being desirable.
Remove StrNCpy() as it is now unused.
In some cases, namestrcpy() is the more appropriate function to use.
While we're here, simplify the API of namestrcpy(): Remove the return
value, don't check for NULL input. Nothing was using that anyway.
Also, remove a few unused name-related functions.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/44f5e198-36f6-6cdb-7fa9-60e34784daae%402ndquadrant.com
Any libpq client can use the header. Clients include backend components
postgres_fdw, dblink, and logical replication apply worker. Back-patch
to v10, because another fix needs this. In released branches, just copy
the header and keep the original.
Hostile objects located within the installation-time search_path could
capture references in an extension's installation or upgrade script.
If the extension is being installed with superuser privileges, this
opens the door to privilege escalation. While such hazards have existed
all along, their urgency increases with the v13 "trusted extensions"
feature, because that lets a non-superuser control the installation path
for a superuser-privileged script. Therefore, make a number of changes
to make such situations more secure:
* Tweak the construction of the installation-time search_path to ensure
that references to objects in pg_catalog can't be subverted; and
explicitly add pg_temp to the end of the path to prevent attacks using
temporary objects.
* Disable check_function_bodies within installation/upgrade scripts,
so that any security gaps in SQL-language or PL-language function bodies
cannot create a risk of unwanted installation-time code execution.
* Adjust lookup of type input/receive functions and join estimator
functions to complain if there are multiple candidate functions. This
prevents capture of references to functions whose signature is not the
first one checked; and it's arguably more user-friendly anyway.
* Modify various contrib upgrade scripts to ensure that catalog
modification queries are executed with secure search paths. (These
are in-place modifications with no extension version changes, since
it is the update process itself that is at issue, not the end result.)
Extensions that depend on other extensions cannot be made fully secure
by these methods alone; therefore, revert the "trusted" marking that
commit eb67623c9 applied to earthdistance and hstore_plperl, pending
some better solution to that set of issues.
Also add documentation around these issues, to help extension authors
write secure installation scripts.
Patch by me, following an observation by Andres Freund; thanks
to Noah Misch for review.
Security: CVE-2020-14350
Since commit efc77cf5f, an indexed query using <@ has required a
full-index scan, so that it actually performs worse than a plain seqscan
would do. As I noted at the time, we'd be better off to not treat <@ as
being indexable by such indexes at all; and that's what this patch does.
It would have been difficult to remove these opclass members without
dropping the whole opclass before commit 9f9682783 fixed GiST opclass
member dependency rules, but now it's quite simple, so let's do it.
I left the existing support code in place for the time being, with
comments noting it's now unreachable. At some point, perhaps we should
remove that code in favor of throwing an error telling people to upgrade
the extension version.
Discussion: https://postgr.es/m/2176979.1596389859@sss.pgh.pa.us
Discussion: https://postgr.es/m/458.1565114141@sss.pgh.pa.us
Teach contrib/amcheck's bt_index_check() function to check agreement
between siblings links. The left sibling's right link should point to a
right sibling page whose left link points back to the same original left
sibling. This extends a check that bt_index_parent_check() always
performed to bt_index_check().
This is the first time amcheck has been taught to perform buffer lock
coupling, which we have explicitly avoided up until now. The sibling
link check tends to catch a lot of real world index corruption with
little overhead, so it seems worth accepting the complexity. Note that
the new lock coupling logic would not work correctly on replica servers
without the changes made by commits 0a7d771f and 9a9db08a (there could
be false positives without those changes).
Author: Andrey Borodin, Peter Geoghegan
Discussion: https://postgr.es/m/0EB0CFA8-CBD8-4296-8049-A2C0F28FAE8C@yandex-team.ru
Commit 7259736a6e added the capability to stream changes in ReorderBuffer
which has some tests to test the streaming mode. It is quite possible that
while this test is running a parallel transaction could be logged by
autovacuum. Such a transaction won't perform any insert/update/delete to
non-catalog tables so will be shown as an empty transaction. Fix it by
skipping the empty transactions during this test.
Per report by buildfarm.
Instead of serializing the transaction to disk after reaching the
logical_decoding_work_mem limit in memory, we consume the changes we have
in memory and invoke stream API methods added by commit 45fdc9738b.
However, sometimes if we have incomplete toast or speculative insert we
spill to the disk because we can't generate the complete tuple and stream.
And, as soon as we get the complete tuple we stream the transaction
including the serialized changes.
We can do this incremental processing thanks to having assignments
(associating subxact with toplevel xacts) in WAL right away, and
thanks to logging the invalidation messages at each command end. These
features are added by commits 0bead9af48 and c55040ccd0 respectively.
Now that we can stream in-progress transactions, the concurrent aborts
may cause failures when the output plugin consults catalogs (both system
and user-defined).
We handle such failures by returning ERRCODE_TRANSACTION_ROLLBACK
sqlerrcode from system table scan APIs to the backend or WALSender
decoding a specific uncommitted transaction. The decoding logic on the
receipt of such a sqlerrcode aborts the decoding of the current
transaction and continue with the decoding of other transactions.
We have ReorderBufferTXN pointer in each ReorderBufferChange by which we
know which xact it belongs to. The output plugin can use this to decide
which changes to discard in case of stream_abort_cb (e.g. when a subxact
gets discarded).
We also provide a new option via SQL APIs to fetch the changes being
streamed.
Author: Dilip Kumar, Tomas Vondra, Amit Kapila, Nikhil Sontakke
Reviewed-by: Amit Kapila, Kuntal Ghosh, Ajin Cherian
Tested-by: Neha Sharma, Mahendra Singh Thalor and Ajin Cherian
Discussion: https://postgr.es/m/688b0b7f-2f6c-d827-c27b-216a8e3ea700@2ndquadrant.com
This will be helpful if it ever proves necessary to revoke an opclass's
support for deduplication.
Backpatch: 13-, where nbtree deduplication was introduced.
Currently, page unlink leaves remaining items "as is", but replay of
corresponding WAL-record re-initializes page leaving it with no items.
For the sake of consistency, this commit makes primary delete all the items
during page unlink as well.
Thanks to this change, we now don't mask contents of deleted btree page for
WAL consistency checking.
Discussion: https://postgr.es/m/CAPpHfdt_OTyQpXaPJcWzV2N-LNeNJseNB-K_A66qG%3DL518VTFw%40mail.gmail.com
Author: Alexander Korotkov
Reviewed-by: Peter Geoghegan
This allows AM-specific knowledge to be applied during creation of
pg_amop and pg_amproc entries. Specifically, the AM knows better than
core code which entries to consider as required or optional. Giving
the latter entries the appropriate sort of dependency allows them to
be dropped without taking out the whole opclass or opfamily; which
is something we'd like to have to correct obsolescent entries in
extensions.
This callback also opens the door to performing AM-specific validity
checks during opclass creation, rather than hoping than an opclass
developer will remember to test with "amvalidate". For the most part
I've not actually added any such checks yet; that can happen in a
follow-on patch. (Note that we shouldn't remove any tests from
"amvalidate", as those are still needed to cross-check manually
constructed entries in the initdb data. So adding tests to
"amadjustmembers" will be somewhat duplicative, but it seems like
a good idea anyway.)
Patch by me, reviewed by Alexander Korotkov, Hamid Akhtar, and
Anastasia Lubennikova.
Discussion: https://postgr.es/m/4578.1565195302@sss.pgh.pa.us
Commit eba77534 fixed an amcheck false positive bug involving
inconsistencies in TOAST input state between table and index. A test
case was added that verified that such an inconsistency didn't result in
a spurious corruption related error.
Test coverage from the test was accidentally lost by commit 501e41dd,
which propagated ALTER TABLE ... SET STORAGE attstorage state to
indexes. This broke the test because the test specifically relied on
attstorage not being propagated. This artificially forced there to be
index tuples whose datums were equivalent to the datums in the heap
without the datums actually being bitwise equal.
Fix this by updating pg_attribute directly instead. Commit 501e41dd
made similar changes to a test_decoding TOAST-related test case which
made the same assumption, but overlooked the amcheck test case.
Backpatch: 11-, just like commit eba77534 (and commit 501e41dd).
Avoid repeatedly calling lseek(SEEK_END) during recovery by caching
the size of each fork. For now, we can't use the same technique in
other processes, because we lack a shared invalidation mechanism.
Do this by generalizing the pre-existing caching used by FSM and VM
to support all forks.
Discussion: https://postgr.es/m/CAEepm%3D3SSw-Ty1DFcK%3D1rU-K6GSzYzfdD4d%2BZwapdN7dTa6%3DnQ%40mail.gmail.com
This commit makes pg_stat_statements track the total number
of rows retrieved or affected by CREATE TABLE AS, SELECT INTO,
CREATE MATERIALIZED VIEW and FETCH commands.
Suggested-by: Pascal Legrand
Author: Fujii Masao
Reviewed-by: Asif Rehman
Discussion: https://postgr.es/m/1584293755198-0.post@n3.nabble.com
This adds seven methods to the output plugin API, adding support for
streaming changes of large in-progress transactions.
* stream_start
* stream_stop
* stream_abort
* stream_commit
* stream_change
* stream_message
* stream_truncate
Most of this is a simple extension of the existing methods, with
the semantic difference that the transaction (or subtransaction)
is incomplete and may be aborted later (which is something the
regular API does not really need to deal with).
This also extends the 'test_decoding' plugin, implementing these
new stream methods.
The stream_start/start_stop are used to demarcate a chunk of changes
streamed for a particular toplevel transaction.
This commit simply adds these new APIs and the upcoming patch to "allow
the streaming mode in ReorderBuffer" will use these APIs.
Author: Tomas Vondra, Dilip Kumar, Amit Kapila
Reviewed-by: Amit Kapila
Tested-by: Neha Sharma and Mahendra Singh Thalor
Discussion: https://postgr.es/m/688b0b7f-2f6c-d827-c27b-216a8e3ea700@2ndquadrant.com
A compressed stream may end with an empty packet. In this case
decompression finishes before reading the empty packet and the
remaining stream packet causes a failure in reading the following
data. This commit makes sure to consume such extra data, avoiding a
failure when decompression the data. This corner case was reproducible
easily with a data length of 16kB, and existed since e94dd6a. A cheap
regression test is added to cover this case based on a random,
incompressible string.
The first attempt of this patch has allowed to find an older failure
within the compression logic of pgcrypto, fixed by b9b6105. This
involved SLES 15 with z390 where a custom flavor of libz gets used.
Bonus thanks to Mark Wong for providing access to the specific
environment.
Reported-by: Frank Gagnepain
Author: Kyotaro Horiguchi, Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/16476-692ef7b84e5fb893@postgresql.org
Backpatch-through: 9.5
contrib/pgcrypto mishandled the case where deflate() does not consume
all of the offered input on the first try. It reset the next_in pointer
to the start of the input instead of leaving it alone, causing the wrong
data to be fed to the next deflate() call.
This has been broken since pgcrypto was committed. The reason for the
lack of complaints seems to be that it's fairly hard to get stock zlib
to not consume all the input, so long as the output buffer is big enough
(which it normally would be in pgcrypto's usage; AFAICT the input is
always going to be packetized into packets no larger than ZIP_OUT_BUF).
However, IBM's zlibNX implementation for AIX evidently will do it
in some cases.
I did not add a test case for this, because I couldn't find one that
would fail with stock zlib. When we put back the test case for
bug #16476, that will cover the zlibNX situation well enough.
While here, write deflate()'s second argument as Z_NO_FLUSH per its
API spec, instead of hard-wiring the value zero.
Per buildfarm results and subsequent investigation.
Discussion: https://postgr.es/m/16476-692ef7b84e5fb893@postgresql.org
This reverts commit 9e10898, after finding out that buildfarm members
running SLES 15 on z390 complain on the compression and decompression
logic of the new test: pipistrelles, barbthroat and steamerduck.
Those hosts are visibly using hardware-specific changes to improve zlib
performance, requiring more investigation.
Thanks to Tom Lane for the discussion.
Discussion: https://postgr.es/m/20200722093749.GA2564@paquier.xyz
Backpatch-through: 9.5
Add infinities that behave the same as they do in the floating-point
data types. Aside from any intrinsic usefulness these may have,
this closes an important gap in our ability to convert floating
values to numeric and/or replace float-based APIs with numeric.
The new values are represented by bit patterns that were formerly
not used (although old code probably would take them for NaNs).
So there shouldn't be any pg_upgrade hazard.
Patch by me, reviewed by Dean Rasheed and Andrew Gierth
Discussion: https://postgr.es/m/606717.1591924582@sss.pgh.pa.us
A compressed stream may end with an empty packet, and PGP decompression
finished before reading this empty packet in the remaining stream. This
caused a failure in pgcrypto, handling this case as corrupted data.
This commit makes sure to consume such extra data, avoiding a failure
when decompression the entire stream. This corner case was reproducible
with a data length of 16kB, and existed since its introduction in
e94dd6a. A cheap regression test is added to cover this case.
Thanks to Jeff Janes for the extra investigation.
Reported-by: Frank Gagnepain
Author: Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/16476-692ef7b84e5fb893@postgresql.org
Backpatch-through: 9.5
One change for getObjectIdentity() has been missed in 2a10fdc, causing
the module to not compile properly. This was actually the only problem,
and it happens that it is easy enough to check the compilation of the
module on Debian after installing libselinux1-dev.
Per buildfarm member rhinoceros.
When using the following functions, users could see various types of
errors of the type "cache lookup failed for OID XXX" with elog(), that
can only be used for internal errors:
* pg_describe_object()
* pg_identify_object()
* pg_identify_object_as_address()
The set of APIs managing object addresses for all object types are made
smarter by gaining a new argument "missing_ok" that allows any caller to
control if an error is raised or not on an undefined object. The SQL
functions listed above are changed to handle the case where an object is
missing.
Regression tests are added for all object types for the cases where
these are undefined. Before this commit, these cases failed with cache
lookup errors, and now they basically return NULL (minus the name of the
object type requested).
Author: Michael Paquier
Reviewed-by: Aleksander Alekseev, Dmitry Dolgov, Daniel Gustafsson,
Álvaro Herrera, Kyotaro Horiguchi
Discussion: https://postgr.es/m/CAB7nPqSZxrSmdHK-rny7z8mi=EAFXJ5J-0RbzDw6aus=wB5azQ@mail.gmail.com