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* Use checkAsUser for selectivity estimator checks, if it's set.Dean Rasheed2019-05-06
| | | | | | | | | | | | | | | | | | | | | | | | | In examine_variable() and examine_simple_variable(), when checking the user's table and column privileges to determine whether to grant access to the pg_statistic data, use checkAsUser for the privilege checks, if it's set. This will be the case if we're accessing the table via a view, to indicate that we should perform privilege checks as the view owner rather than the current user. This change makes this planner check consistent with the check in the executor, so the planner will be able to make use of statistics if the table is accessible via the view. This fixes a performance regression introduced by commit e2d4ef8de8, which affects queries against non-security barrier views in the case where the user doesn't have privileges on the underlying table, but the view owner does. Note that it continues to provide the same safeguards controlling access to pg_statistic for direct table access (in which case checkAsUser won't be set) and for security barrier views, because of the nearby checks on rte->security_barrier and rte->securityQuals. Back-patch to all supported branches because e2d4ef8de8 was. Dean Rasheed, reviewed by Jonathan Katz and Stephen Frost.
* Fix security checks for selectivity estimation functions with RLS.Dean Rasheed2019-05-06
| | | | | | | | | | | | | | | | | | | | | | In commit e2d4ef8de8, security checks were added to prevent user-supplied operators from running over data from pg_statistic unless the user has table or column privileges on the table, or the operator is leakproof. For a table with RLS, however, checking for table or column privileges is insufficient, since that does not guarantee that the user has permission to view all of the column's data. Fix this by also checking for securityQuals on the RTE, and insisting that the operator be leakproof if there are any. Thus the leakproofness check will only be skipped if there are no securityQuals and the user has table or column privileges on the table -- i.e., only if we know that the user has access to all the data in the column. Back-patch to 9.5 where RLS was added. Dean Rasheed, reviewed by Jonathan Katz and Stephen Frost. Security: CVE-2019-10130
* Fix reindexing of pg_class indexes some more.Tom Lane2019-05-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits 3dbb317d3 et al failed under CLOBBER_CACHE_ALWAYS testing. Investigation showed that to reindex pg_class_oid_index, we must suppress accesses to the index (via SetReindexProcessing) before we call RelationSetNewRelfilenode, or at least before we do CommandCounterIncrement therein; otherwise, relcache reloads happening within the CCI may try to fetch pg_class rows using the index's new relfilenode value, which is as yet an empty file. Of course, the point of 3dbb317d3 was that that ordering didn't work either, because then RelationSetNewRelfilenode's own update of the index's pg_class row cannot access the index, should it need to. There are various ways we might have got around that, but Andres Freund came up with a brilliant solution: for a mapped index, we can really just skip the pg_class update altogether. The only fields it was actually changing were relpages etc, but it was just setting them to zeroes which is useless make-work. (Correct new values will be installed at the end of index build.) All pg_class indexes are mapped and probably always will be, so this eliminates the problem by removing work rather than adding it, always a pleasant outcome. Having taught RelationSetNewRelfilenode to do it that way, we can revert the code reordering in reindex_index. (But I left the moved setup code where it was; there seems no reason why it has to run without use of the old index. If you're trying to fix a busted pg_class index, you'll have had to disable system index use altogether to get this far.) Moreover, this means we don't need RelationSetIndexList at all, because reindex_relation's hacking to make "REINDEX TABLE pg_class" work is likewise now unnecessary. We'll leave that code in place in the back branches, but a follow-on patch will remove it in HEAD. In passing, do some minor cleanup for commit 5c1560606 (in HEAD only), notably removing a duplicate newrnode assignment. Patch by me, using a core idea due to Andres Freund. Back-patch to all supported branches, as 3dbb317d3 was. Discussion: https://postgr.es/m/28926.1556664156@sss.pgh.pa.us
* Repair assorted issues in locale data extraction.Tom Lane2019-04-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cache_locale_time (extraction of LC_TIME-related info) had never been taught the lessons we previously learned about extraction of info related to LC_MONETARY and LC_NUMERIC. Specifically, commit 95a777c61 taught PGLC_localeconv() that data coming out of localeconv() was in an encoding determined by the relevant locale, but we didn't realize that there's a similar issue with strftime(). And commit a4930e7ca hardened PGLC_localeconv() against errors occurring partway through, but failed to do likewise for cache_locale_time(). So, rearrange the latter function to perform encoding conversion and not risk failure while it's got the locales set to temporary values. This time around I also changed PGLC_localeconv() to treat it as FATAL if it can't restore the previous settings of the locale values. There is no reason (except possibly OOM) for that to fail, and proceeding with the wrong locale values seems like a seriously bad idea --- especially on Windows where we have to also temporarily change LC_CTYPE. Also, protect against the possibility that we can't identify the codeset reported for LC_MONETARY or LC_NUMERIC; rather than just failing, try to validate the data without conversion. The user-visible symptom this fixes is that if LC_TIME is set to a locale name that implies an encoding different from the database encoding, non-ASCII localized day and month names would be retrieved in the wrong encoding, leading to either unexpected encoding-conversion error reports or wrong output from to_char(). The other possible failure modes are unlikely enough that we've not seen reports of them, AFAIK. The encoding conversion problems do not manifest on Windows, since we'd already created special-case code to handle that issue there. Per report from Juan José Santamaría Flecha. Back-patch to all supported versions. Juan José Santamaría Flecha and Tom Lane Discussion: https://postgr.es/m/CAC+AXB22So5aZm2vZe+MChYXec7gWfr-n-SK-iO091R0P_1Tew@mail.gmail.com
* Fix handling of temp and unlogged tables in FOR ALL TABLES publicationsPeter Eisentraut2019-04-18
| | | | | | | | | | | If a FOR ALL TABLES publication exists, temporary and unlogged tables are ignored for publishing changes. But CheckCmdReplicaIdentity() would still check in that case that such a table has a replica identity set before accepting updates. To fix, have GetRelationPublicationActions() return that such a table publishes no actions. Discussion: https://www.postgresql.org/message-id/f3f151f7-c4dd-1646-b998-f60bd6217dd3@2ndquadrant.com
* postgresql.conf.sample: add proper defaults for include actionsBruce Momjian2019-04-17
| | | | | | | | | | | | | Previously, include actions include_dir, include_if_exists, and include listed commented-out values which were not the defaults, which is inconsistent with other entries. Instead, replace them with '', which is the default value. Reported-by: Emanuel Araújo Discussion: https://postgr.es/m/CAMuTAkYMx6Q27wpELDR3_v9aG443y7ZjeXu15_+1nGUjhMWOJA@mail.gmail.com Backpatch-through: 9.4
* Prevent memory leaks associated with relcache rd_partcheck structures.Tom Lane2019-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | The original coding of generate_partition_qual() just copied the list of predicate expressions into the global CacheMemoryContext, making it effectively impossible to clean up when the owning relcache entry is destroyed --- the relevant code in RelationDestroyRelation() only managed to free the topmost List header :-(. This resulted in a session-lifespan memory leak whenever a table partition's relcache entry is rebuilt. Fortunately, that's not normally a large data structure, and rebuilds shouldn't occur all that often in production situations; but this is still a bug worth fixing back to v10 where the code was introduced. To fix, put the cached expression tree into its own small memory context, as we do with other complicated substructures of relcache entries. Also, deal more honestly with the case that a partition has an empty partcheck list; while that probably isn't a case that's very interesting for production use, it's legal. In passing, clarify comments about how partitioning-related relcache data structures are managed, and add some Asserts that we're not leaking old copies when we overwrite these data fields. Amit Langote and Tom Lane Discussion: https://postgr.es/m/7961.1552498252@sss.pgh.pa.us
* Consistently test for in-use shared memory.Noah Misch2019-04-12
| | | | | | | | | | | | | | | | | | | | | | postmaster startup scrutinizes any shared memory segment recorded in postmaster.pid, exiting if that segment matches the current data directory and has an attached process. When the postmaster.pid file was missing, a starting postmaster used weaker checks. Change to use the same checks in both scenarios. This increases the chance of a startup failure, in lieu of data corruption, if the DBA does "kill -9 `head -n1 postmaster.pid` && rm postmaster.pid && pg_ctl -w start". A postmaster will no longer stop if shmat() of an old segment fails with EACCES. A postmaster will no longer recycle segments pertaining to other data directories. That's good for production, but it's bad for integration tests that crash a postmaster and immediately delete its data directory. Such a test now leaks a segment indefinitely. No "make check-world" test does that. win32_shmem.c already avoided all these problems. In 9.6 and later, enhance PostgresNode to facilitate testing. Back-patch to 9.4 (all supported versions). Reviewed (in earlier versions) by Daniel Gustafsson and Kyotaro HORIGUCHI. Discussion: https://postgr.es/m/20190408064141.GA2016666@rfd.leadboat.com
* Revert "Consistently test for in-use shared memory."Noah Misch2019-04-05
| | | | | | | | | This reverts commits 2f932f71d9f2963bbd201129d7b971c8f5f077fd, 16ee6eaf80a40007a138b60bb5661660058d0422 and 6f0e190056fe441f7cf788ff19b62b13c94f68f3. The buildfarm has revealed several bugs. Back-patch like the original commits. Discussion: https://postgr.es/m/20190404145319.GA1720877@rfd.leadboat.com
* Consistently test for in-use shared memory.Noah Misch2019-04-03
| | | | | | | | | | | | | | | | | | | | | postmaster startup scrutinizes any shared memory segment recorded in postmaster.pid, exiting if that segment matches the current data directory and has an attached process. When the postmaster.pid file was missing, a starting postmaster used weaker checks. Change to use the same checks in both scenarios. This increases the chance of a startup failure, in lieu of data corruption, if the DBA does "kill -9 `head -n1 postmaster.pid` && rm postmaster.pid && pg_ctl -w start". A postmaster will no longer recycle segments pertaining to other data directories. That's good for production, but it's bad for integration tests that crash a postmaster and immediately delete its data directory. Such a test now leaks a segment indefinitely. No "make check-world" test does that. win32_shmem.c already avoided all these problems. In 9.6 and later, enhance PostgresNode to facilitate testing. Back-patch to 9.4 (all supported versions). Reviewed by Daniel Gustafsson and Kyotaro HORIGUCHI. Discussion: https://postgr.es/m/20130911033341.GD225735@tornado.leadboat.com
* Update HINT for pre-existing shared memory block.Noah Misch2019-03-31
| | | | | | | | | | | | One should almost always terminate an old process, not use a manual removal tool like ipcrm. Removal of the ipcclean script eleven years ago (39627b1ae680cba44f6e56ca5facec4fdbfe9495) and its non-replacement corroborate that manual shm removal is now a niche goal. Back-patch to 9.4 (all supported versions). Reviewed by Daniel Gustafsson and Kyotaro HORIGUCHI. Discussion: https://postgr.es/m/20180812064815.GB2301738@rfd.leadboat.com
* Fix off-by-one error in txid_status().Thomas Munro2019-03-27
| | | | | | | | | | | | | The transaction ID returned by GetNextXidAndEpoch() is in the future, so we can't attempt to access its status or we might try to read a CLOG page that doesn't exist. The > vs >= confusion probably stemmed from the choice of a variable name containing the word "last" instead of "next", so fix that too. Back-patch to 10 where the function arrived. Author: Thomas Munro Discussion: https://postgr.es/m/CA%2BhUKG%2Buua_BV5cyfsioKVN2d61Lukg28ECsWTXKvh%3DBtN2DPA%40mail.gmail.com
* Remove inadequate check for duplicate "xml" PI.Tom Lane2019-03-23
| | | | | | I failed to think about PIs starting with "xml". We don't really need this check at all, so just take it out. Oversight in commit 8d1dadb25 et al.
* Revert strlen -> strnlen optimization pre-v11.Tom Lane2019-03-23
| | | | | We don't have a src/port substitute for that function in older branches, so it fails on platforms lacking the function natively. Per buildfarm.
* Accept XML documents when xmloption = content, as required by SQL:2006+.Tom Lane2019-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | Previously we were using the SQL:2003 definition, which doesn't allow this, but that creates a serious dump/restore gotcha: there is no setting of xmloption that will allow all valid XML data. Hence, switch to the 2006 definition. Since libxml doesn't accept <!DOCTYPE> directives in the mode we use for CONTENT parsing, the implementation is to detect <!DOCTYPE> in the input and switch to DOCUMENT parsing mode. This should not cost much, because <!DOCTYPE> should be close to the front of the input if it's there at all. It's possible that this causes the error messages for malformed input to be slightly different than they were before, if said input includes <!DOCTYPE>; but that does not seem like a big problem. In passing, buy back a few cycles in parsing of large XML documents by not doing strlen() of the whole input in parse_xml_decl(). Back-patch because dump/restore failures are not nice. This change shouldn't break any cases that worked before, so it seems safe to back-patch. Chapman Flack (revised a bit by me) Discussion: https://postgr.es/m/CAN-V+g-6JqUQEQZ55Q3toXEN6d5Ez5uvzL4VR+8KtvJKj31taw@mail.gmail.com
* Disallow NaN as a value for floating-point GUCs.Tom Lane2019-03-10
| | | | | | | | | | | | | | | | | | None of the code that uses GUC values is really prepared for them to hold NaN, but parse_real() didn't have any defense against accepting such a value. Treat it the same as a syntax error. I haven't attempted to analyze the exact consequences of setting any of the float GUCs to NaN, but since they're quite unlikely to be good, this seems like a back-patchable bug fix. Note: we don't need an explicit test for +-Infinity because those will be rejected by existing range checks. I added a regression test for that in HEAD, but not older branches because the spelling of the value in the error message will be platform-dependent in branches where we don't always use port/snprintf.c. Discussion: https://postgr.es/m/1798.1552165479@sss.pgh.pa.us
* Improve documentation of data_sync_retryMichael Paquier2019-02-28
| | | | | | | | Reflecting an updated parameter value requires a server restart, which was not mentioned in the documentation and in postgresql.conf.sample. Reported-by: Thomas Poty Discussion: https://postgr.es/m/15659-0cd812f13027a2d8@postgresql.org
* Fix inconsistent out-of-memory error reporting in dsa.c.Thomas Munro2019-02-25
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit 16be2fd1 introduced the flag DSA_ALLOC_NO_OOM to control whether the DSA allocator would raise an error or return InvalidDsaPointer on failure to allocate. One edge case was not handled correctly: if we fail to allocate an internal "span" object for a large allocation, we would always return InvalidDsaPointer regardless of the flag; a caller not expecting that could then dereference a null pointer. This is a plausible explanation for a one-off report of a segfault. Remove a redundant pair of braces so that all three stanzas that handle DSA_ALLOC_NO_OOM match in style, for visual consistency. While fixing inconsistencies, if FreePageManagerGet() can't supply the pages that our book-keeping says it should be able to supply, then we should always report a FATAL error. Previously we treated that as a regular allocation failure in one code path, but as a FATAL condition in another. Back-patch to 10, where dsa.c landed. Author: Thomas Munro Reported-by: Jakub Glapa Discussion: https://postgr.es/m/CAEepm=2oPqXxyWQ-1o60tpOLrwkw=VpgNXqqF1VN2EyO9zKGQw@mail.gmail.com
* Fix rare dsa_allocate() failures due to freepage.c corruption.Thomas Munro2019-02-13
| | | | | | | | | | | | | | | | | | In a corner case, a btree page was allocated during a clean-up operation that could cause the tracking of the largest contiguous span of free space to get out of whack. That was supposed to be prevented by the use of the "soft" flag to avoid allocating internal pages during incidental clean-up work, but the flag was ignored in the case where the FPM was promoted from singleton format to btree format. Repair. Remove an obsolete comment in passing. Back-patch to 10, where freepage.c arrived (as support for dsa.c). Author: Robert Haas Diagnosed-by: Thomas Munro and Robert Haas Reported-by: Justin Pryzby, Rick Otten, Sand Stone, Arne Roland and others Discussion: https://postgr.es/m/CAMAYy4%2Bw3NTBM5JLWFi8twhWK4%3Dk_5L4nV5%2BbYDSPu8r4b97Zg%40mail.gmail.com
* Defend against null error message reported by libxml2.Tom Lane2019-02-08
| | | | | | | | | | | | | | While this isn't really supposed to happen, it can occur in OOM situations and perhaps others. Instead of crashing, substitute "(no message provided)". I didn't worry about localizing this text, since we aren't localizing anything else here; besides, if we're on the edge of OOM, it's unlikely gettext() would work. Report and fix by Sergio Conde Gómez in bug #15624. Discussion: https://postgr.es/m/15624-4dea54091a2864e6@postgresql.org
* Fix a crash in logical replicationPeter Eisentraut2019-01-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The bug was that determining which columns are part of the replica identity index using RelationGetIndexAttrBitmap() would run eval_const_expressions() on index expressions and predicates across all indexes of the table, which in turn might require a snapshot, but there wasn't one set, so it crashes. There were actually two separate bugs, one on the publisher and one on the subscriber. To trigger the bug, a table that is part of a publication or subscription needs to have an index with a predicate or expression that lends itself to constant expressions simplification. The fix is to avoid the constant expressions simplification in RelationGetIndexAttrBitmap(), so that it becomes safe to call in these contexts. The constant expressions simplification comes from the calls to RelationGetIndexExpressions()/RelationGetIndexPredicate() via BuildIndexInfo(). But RelationGetIndexAttrBitmap() calling BuildIndexInfo() is overkill. The latter just takes pg_index catalog information, packs it into the IndexInfo structure, which former then just unpacks again and throws away. We can just do this directly with less overhead and skip the troublesome calls to eval_const_expressions(). This also removes the awkward cross-dependency between relcache.c and index.c. Bug: #15114 Reported-by: Петър Славов <pet.slavov@gmail.com> Reviewed-by: Noah Misch <noah@leadboat.com> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://www.postgresql.org/message-id/flat/152110589574.1223.17983600132321618383@wrigleys.postgresql.org/
* Remove useless bms_copy step in RelationGetIndexAttrBitmap.Tom Lane2019-01-21
| | | | | | | | | | Seems to be from a bad case of copy-and-paste-itis in commit 665d1fad9. It wouldn't be quite so annoying if it didn't contradict the comment half a dozen lines above. David Rowley Discussion: https://postgr.es/m/CAKJS1f95Dyf8Qkdz4W+PbCmT-HTb54tkqUCC8isa2RVgSJ_pXQ@mail.gmail.com
* Flush relcache entries when their FKs are meddled withAlvaro Herrera2019-01-21
| | | | | | | | | | | | | | | Back in commit 100340e2dcd0, we made relcache entries keep lists of the foreign keys applying to the relation -- but we forgot to update CacheInvalidateHeapTuple to flush those entries when new FKs got created or existing ones updated/deleted. No bugs appear to have been reported that would be explained by this ommission, but I noticed the problem while working on an unrelated bugfix which clearly showed it. Fix by adding relcache flush on relevant foreign key changes. Backpatch to 9.6, like the aforementioned commit. Discussion: https://postgr.es/m/201901211927.7mmhschxlejh@alvherre.pgsql Reviewed-by: Tom Lane
* Fix minor typo in dsa.c.Thomas Munro2018-11-29
| | | | | Author: Takeshi Ideriha Discussion: https://postgr.es/m/4E72940DA2BF16479384A86D54D0988A6F3BF22D%40G01JPEXMBKW04
* Fix float-to-integer coercions to handle edge cases correctly.Tom Lane2018-11-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | ftoi4 and its sibling coercion functions did their overflow checks in a way that looked superficially plausible, but actually depended on an assumption that the MIN and MAX comparison constants can be represented exactly in the float4 or float8 domain. That fails in ftoi4, ftoi8, and dtoi8, resulting in a possibility that values near the MAX limit will be wrongly converted (to negative values) when they need to be rejected. Also, because we compared before rounding off the fractional part, the other three functions threw errors for values that really ought to get rounded to the min or max integer value. Fix by doing rint() first (requiring an assumption that it handles NaN and Inf correctly; but dtoi8 and ftoi8 were assuming that already), and by comparing to values that should coerce to float exactly, namely INTxx_MIN and -INTxx_MIN. Also remove some random cosmetic discrepancies between these six functions. This back-patches commits cbdb8b4c0 and 452b637d4. In the 9.4 branch, also back-patch the portion of 62e2a8dc2 that added PG_INTnn_MIN and related constants to c.h, so that these functions can rely on them. Per bug #15519 from Victor Petrovykh. Patch by me; thanks to Andrew Gierth for analysis and discussion. Discussion: https://postgr.es/m/15519-4fc785b483201ff1@postgresql.org
* PANIC on fsync() failure.Thomas Munro2018-11-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On some operating systems, it doesn't make sense to retry fsync(), because dirty data cached by the kernel may have been dropped on write-back failure. In that case the only remaining copy of the data is in the WAL. A subsequent fsync() could appear to succeed, but not have flushed the data. That means that a future checkpoint could apparently complete successfully but have lost data. Therefore, violently prevent any future checkpoint attempts by panicking on the first fsync() failure. Note that we already did the same for WAL data; this change extends that behavior to non-temporary data files. Provide a GUC data_sync_retry to control this new behavior, for users of operating systems that don't eject dirty data, and possibly forensic/testing uses. If it is set to on and the write-back error was transient, a later checkpoint might genuinely succeed (on a system that does not throw away buffers on failure); if the error is permanent, later checkpoints will continue to fail. The GUC defaults to off, meaning that we panic. Back-patch to all supported releases. There is still a narrow window for error-loss on some operating systems: if the file is closed and later reopened and a write-back error occurs in the intervening time, but the inode has the bad luck to be evicted due to memory pressure before we reopen, we could miss the error. A later patch will address that with a scheme for keeping files with dirty data open at all times, but we judge that to be too complicated to back-patch. Author: Craig Ringer, with some adjustments by Thomas Munro Reported-by: Craig Ringer Reviewed-by: Robert Haas, Thomas Munro, Andres Freund Discussion: https://postgr.es/m/20180427222842.in2e4mibx45zdth5%40alap3.anarazel.de
* Disallow setting client_min_messages higher than ERROR.Tom Lane2018-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously it was possible to set client_min_messages to FATAL or PANIC, which had the effect of suppressing transmission of regular ERROR messages to the client. Perhaps that seemed like a useful option in the past, but the trouble with it is that it breaks guarantees that are explicitly made in our FE/BE protocol spec about how a query cycle can end. While libpq and psql manage to cope with the omission, that's mostly because they are not very bright; client libraries that have more semantic knowledge are likely to get confused. Notably, pgODBC doesn't behave very sanely. Let's fix this by getting rid of the ability to set client_min_messages above ERROR. In HEAD, just remove the FATAL and PANIC options from the set of allowed enum values for client_min_messages. (This change also affects trace_recovery_messages, but that's OK since these aren't useful values for that variable either.) In the back branches, there was concern that rejecting these values might break applications that are explicitly setting things that way. I'm pretty skeptical of that argument, but accommodate it by accepting these values and then internally setting the variable to ERROR anyway. In all branches, this allows a couple of tiny simplifications in the logic in elog.c, so do that. Also respond to the point that was made that client_min_messages has exactly nothing to do with the server's logging behavior, and therefore does not belong in the "When To Log" subsection of the documentation. The "Statement Behavior" subsection is a better match, so move it there. Jonah Harris and Tom Lane Discussion: https://postgr.es/m/7809.1541521180@sss.pgh.pa.us Discussion: https://postgr.es/m/15479-ef0f4cc2fd995ca2@postgresql.org
* GUC: adjust effective_cache_size SQL descriptionsBruce Momjian2018-11-06
| | | | | | | | | | Follow on patch for commit 3e0f1a4741f564c1a2fa6e944729d6967355d8c7. Reported-by: Peter Eisentraut Discussion: https://postgr.es/m/369ec766-b947-51bd-4dad-6fb9e026439f@2ndquadrant.com Backpatch-through: 9.4
* GUC: adjust effective_cache_size docs and SQL descriptionBruce Momjian2018-11-02
| | | | | | | | | | | Clarify that effective_cache_size is both kernel buffers and shared buffers. Reported-by: nat@makarevitch.org Discussion: https://postgr.es/m/153685164808.22334.15432535018443165207@wrigleys.postgresql.org Backpatch-through: 9.3
* Add missing quote_identifier calls for CREATE TRIGGER ... REFERENCING.Tom Lane2018-10-19
| | | | | | | | | | | Mixed-case names for transition tables weren't dumped correctly. Oversight in commit 8c48375e5, per bug #15440 from Karl Czajkowski. In passing, I couldn't resist a bit of code beautification. Back-patch to v10 where this was introduced. Discussion: https://postgr.es/m/15440-02d1468e94d63d76@postgresql.org
* Avoid statically allocating gmtsub()'s timezone workspace.Tom Lane2018-10-16
| | | | | | | | | | | | | | | | | | | | | | | localtime.c's "struct state" is a rather large object, ~23KB. We were statically allocating one for gmtsub() to use to represent the GMT timezone, even though that function is not at all heavily used and is never reached in most backends. Let's malloc it on-demand, instead. This does pose the question of how to handle a malloc failure, but there's already a well-defined error report convention here, ie set errno and return NULL. We have but one caller of pg_gmtime in HEAD, and two in back branches, neither of which were troubling to check for error. Make them do so. The possible errors are sufficiently unlikely (out-of-range timestamp, and now malloc failure) that I think elog() is adequate. Back-patch to all supported branches to keep our copies of the IANA timezone code in sync. This particular change is in a stanza that already differs from upstream, so it's a wash for maintenance purposes --- but only as long as we keep the branches the same. Discussion: https://postgr.es/m/20181015200754.7y7zfuzsoux2c4ya@alap3.anarazel.de
* MAXALIGN the target address where we store flattened value.Amit Kapila2018-10-03
| | | | | | | | | | | | The API (EOH_flatten_into) that flattens the expanded value representation expects the target address to be maxaligned. All it's usage adhere to that principle except when serializing datums for parallel query. Fix that usage. Diagnosed-by: Tom Lane Author: Tom Lane and Amit Kapila Backpatch-through: 9.6 Discussion: https://postgr.es/m/11629.1536550032@sss.pgh.pa.us
* Fix corner-case failures in has_foo_privilege() family of functions.Tom Lane2018-10-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The variants of these functions that take numeric inputs (OIDs or column numbers) are supposed to return NULL rather than failing on bad input; this rule reduces problems with snapshot skew when queries apply the functions to all rows of a catalog. has_column_privilege() had careless handling of the case where the table OID didn't exist. You might get something like this: select has_column_privilege(9999,'nosuchcol','select'); ERROR: column "nosuchcol" of relation "(null)" does not exist or you might get a crash, depending on the platform's printf's response to a null string pointer. In addition, while applying the column-number variant to a dropped column returned NULL as desired, applying the column-name variant did not: select has_column_privilege('mytable','........pg.dropped.2........','select'); ERROR: column "........pg.dropped.2........" of relation "mytable" does not exist It seems better to make this case return NULL as well. Also, the OID-accepting variants of has_foreign_data_wrapper_privilege, has_server_privilege, and has_tablespace_privilege didn't follow the principle of returning NULL for nonexistent OIDs. Superusers got TRUE, everybody else got an error. Per investigation of Jaime Casanova's report of a new crash in HEAD. These behaviors have been like this for a long time, so back-patch to all supported branches. Patch by me; thanks to Stephen Frost for discussion and review Discussion: https://postgr.es/m/CAJGNTeP=-6Gyqq5TN9OvYEydi7Fv1oGyYj650LGTnW44oAzYCg@mail.gmail.com
* Fix assorted bugs in pg_get_partition_constraintdef().Tom Lane2018-09-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It failed if passed a nonexistent relation OID, or one that was a non-heap relation, because of blindly applying heap_open to a user-supplied OID. This is not OK behavior for a SQL-exposed function; we have a project policy that we should return NULL in such cases. Moreover, since pg_get_partition_constraintdef ought now to work on indexes, restricting it to heaps is flat wrong anyway. The underlying function generate_partition_qual() wasn't on board with indexes having partition quals either, nor for that matter with rels having relispartition set but yet null relpartbound. (One wonders whether the person who wrote the function comment blocks claiming that these functions allow a missing relpartbound had ever tested it.) Fix by testing relispartition before opening the rel, and by using relation_open not heap_open. (If any other relkinds ever grow the ability to have relispartition set, the code will work with them automatically.) Also, don't reject null relpartbound in generate_partition_qual. Back-patch to v11, and all but the null-relpartbound change to v10. (It's not really necessary to change generate_partition_qual at all in v10, but I thought s/heap_open/relation_open/ would be a good idea anyway just to keep the code in sync with later branches.) Per report from Justin Pryzby. Discussion: https://postgr.es/m/20180927200020.GJ776@telsasoft.com
* Fix over-allocation of space for array_out()'s result string.Tom Lane2018-09-24
| | | | | | | | | | | | | | | | | | | | | | | | array_out overestimated the space needed for its output, possibly by a very substantial amount if the array is multi-dimensional, because of wrong order of operations in the loop that counts the number of curly-brace pairs needed. While the output string is normally short-lived, this could still cause problems in extreme cases. An additional minor error was that it counted one more delimiter than is actually needed. Repair those errors, add an Assert that the space is now correctly calculated, and make some minor improvements in the comments. I also failed to resist the temptation to get rid of an integer modulus operation per array element; a simple comparison is sufficient. This bug dates clear back to Berkeley days, so back-patch to all supported versions. Keiichi Hirobe, minor additional work by me Discussion: https://postgr.es/m/CAH=EFxE9W0tRvQkixR2XJRRCToUYUEDkJZk6tnADXugPBRdcdg@mail.gmail.com
* Initialize random() in bootstrap/stand-alone postgres and in initdb.Noah Misch2018-09-23
| | | | | | | | | | | | | | | | | | | | | | This removes a difference between the standard IsUnderPostmaster execution environment and that of --boot and --single. In a stand-alone backend, "SELECT random()" always started at the same seed. On a system capable of using posix shared memory, initdb could still conclude "selecting dynamic shared memory implementation ... sysv". Crashed --boot or --single postgres processes orphaned shared memory objects having names that collided with the not-actually-random names that initdb probed. The sysv fallback appeared after ten crashes of --boot or --single postgres. Since --boot and --single are rare in production use, systems used for PostgreSQL development are the principal candidate to notice this symptom. Back-patch to 9.3 (all supported versions). PostgreSQL 9.4 introduced dynamic shared memory, but 9.3 does share the "SELECT random()" problem. Reviewed by Tom Lane and Kyotaro HORIGUCHI. Discussion: https://postgr.es/m/20180915221546.GA3159382@rfd.leadboat.com
* Use size_t consistently in dsa.{ch}.Thomas Munro2018-09-22
| | | | | | | | Takeshi Ideriha complained that there is a mixture of Size and size_t in dsa.c and corresponding header. Let's use size_t. Back-patch to 10 where dsa.c landed, to make future back-patching easy. Discussion: https://postgr.es/m/4E72940DA2BF16479384A86D54D0988A6F19ABD9%40G01JPEXMBKW04
* Fix segment_bins corruption in dsa.c.Thomas Munro2018-09-20
| | | | | | | | | | | | | | | | If a segment has been freed by dsa.c because it is entirely empty, other backends must make sure to unmap it before following links to new segments that might happen to have the same index number, or they could finish up looking at a defunct segment and then corrupt the segment_bins lists. The correct protocol requires checking freed_segment_counter after acquiring the area lock and before resolving any index number to a segment. Add the missing checks and an assertion. Back-patch to 10, where dsa.c first arrived. Author: Thomas Munro Reported-by: Tomas Vondra Discussion: https://postgr.es/m/CAEepm%3D0thg%2Bja5zGVa7jBy-uqyHrTqTm8HGhEOtMmigGrAqTbw%40mail.gmail.com
* Fix parsetree representation of XMLTABLE(XMLNAMESPACES(DEFAULT ...)).Tom Lane2018-09-17
| | | | | | | | | | | | | | | | | | | | | | | The original coding for XMLTABLE thought it could represent a default namespace by a T_String Value node with a null string pointer. That's not okay, though; in particular outfuncs.c/readfuncs.c are not on board with such a representation, meaning you'll get a null pointer crash if you try to store a view or rule containing this construct. To fix, change the parsetree representation so that we have a NULL list element, instead of a bogus Value node. This isn't really a functional limitation since default XML namespaces aren't yet implemented in the executor; you'd just get "DEFAULT namespace is not supported" anyway. But crashes are not nice, so back-patch to v10 where this syntax was added. Ordinarily we'd consider a parsetree representation change to be un-backpatchable; but since existing releases would crash on the way to storing such constructs, there can't be any existing views/rules to be incompatible with. Per report from Andrey Lepikhov. Discussion: https://postgr.es/m/3690074f-abd2-56a9-144a-aa5545d7a291@postgrespro.ru
* Repair bug in regexp split performance improvements.Andrew Gierth2018-09-12
| | | | | | | | | | | | | | | | Commit c8ea87e4b introduced a temporary conversion buffer for substrings extracted during regexp splits. Unfortunately the code that sized it was failing to ignore the effects of ignored degenerate regexp matches, so for regexp_split_* calls it could under-size the buffer in such cases. Fix, and add some regression test cases (though those will only catch the bug if run in a multibyte encoding). Backpatch to 9.3 as the faulty code was. Thanks to the PostGIS project, Regina Obe and Paul Ramsey for the report (via IRC) and assistance in analysis. Patch by me.
* Limit depth of forced recursion for CLOBBER_CACHE_RECURSIVELY.Tom Lane2018-09-07
| | | | | | | | | | | | It's somewhat surprising that we got away with this before. (Actually, since nobody tests this routinely AFAIK, it might've been broken for awhile. But it's definitely broken in the wake of commit f868a8143.) It seems sufficient to limit the forced recursion to a small number of levels. Back-patch to all supported branches, like the preceding patch. Discussion: https://postgr.es/m/12259.1532117714@sss.pgh.pa.us
* Avoid using potentially-under-aligned page buffers.Tom Lane2018-09-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's a project policy against using plain "char buf[BLCKSZ]" local or static variables as page buffers; preferred style is to palloc or malloc each buffer to ensure it is MAXALIGN'd. However, that policy's been ignored in an increasing number of places. We've apparently got away with it so far, probably because (a) relatively few people use platforms on which misalignment causes core dumps and/or (b) the variables chance to be sufficiently aligned anyway. But this is not something to rely on. Moreover, even if we don't get a core dump, we might be paying a lot of cycles for misaligned accesses. To fix, invent new union types PGAlignedBlock and PGAlignedXLogBlock that the compiler must allocate with sufficient alignment, and use those in place of plain char arrays. I used these types even for variables where there's no risk of a misaligned access, since ensuring proper alignment should make kernel data transfers faster. I also changed some places where we had been palloc'ing short-lived buffers, for coding style uniformity and to save palloc/pfree overhead. Since this seems to be a live portability hazard (despite the lack of field reports), back-patch to all supported versions. Patch by me; thanks to Michael Paquier for review. Discussion: https://postgr.es/m/1535618100.1286.3.camel@credativ.de
* Avoid quadratic slowdown in regexp match/split functions.Andrew Gierth2018-08-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | regexp_matches, regexp_split_to_table and regexp_split_to_array all work by compiling a list of match positions as character offsets (NOT byte positions) in the source string. Formerly, they then used text_substr to extract the matched text; but in a multi-byte encoding, that counts the characters in the string, and the characters needed to reach the starting byte position, on every call. Accordingly, the performance degraded as the product of the input string length and the number of match positions, such that splitting a string of a few hundred kbytes could take many minutes. Repair by keeping the wide-character copy of the input string available (only in the case where encoding_max_length is not 1) after performing the match operation, and extracting substrings from that instead. This reduces the complexity to being linear in the number of result bytes, discounting the actual regexp match itself (which is not affected by this patch). In passing, remove cleanup using retail pfree() which was obsoleted by commit ff428cded (Feb 2008) which made cleanup of SRF multi-call contexts automatic. Also increase (to ~134 million) the maximum number of matches and provide an error message when it is reached. Backpatch all the way because this has been wrong forever. Analysis and patch by me; review by Kaiting Chen. Discussion: https://postgr.es/m/87pnyn55qh.fsf@news-spur.riddles.org.uk see also https://postgr.es/m/87lg996g4r.fsf@news-spur.riddles.org.uk
* Fix typoAlvaro Herrera2018-08-21
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* Clean up assorted misuses of snprintf()'s result value.Tom Lane2018-08-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a small number of places that were testing the result of snprintf() but doing so incorrectly. The right test for buffer overrun, per C99, is "result >= bufsize" not "result > bufsize". Some places were also checking for failure with "result == -1", but the standard only says that a negative value is delivered on failure. (Note that this only makes these places correct if snprintf() delivers C99-compliant results. But at least now these places are consistent with all the other places where we assume that.) Also, make psql_start_test() and isolation_start_test() check for buffer overrun while constructing their shell commands. There seems like a higher risk of overrun, with more severe consequences, here than there is for the individual file paths that are made elsewhere in the same functions, so this seemed like a worthwhile change. Also fix guc.c's do_serialize() to initialize errno = 0 before calling vsnprintf. In principle, this should be unnecessary because vsnprintf should have set errno if it returns a failure indication ... but the other two places this coding pattern is cribbed from don't assume that, so let's be consistent. These errors are all very old, so back-patch as appropriate. I think that only the shell command overrun cases are even theoretically reachable in practice, but there's not much point in erroneous error checks. Discussion: https://postgr.es/m/17245.1534289329@sss.pgh.pa.us
* Further fixes for quoted-list GUC values in pg_dump and ruleutils.c.Tom Lane2018-07-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits 742869946 et al turn out to be a couple bricks shy of a load. We were dumping the stored values of GUC_LIST_QUOTE variables as they appear in proconfig or setconfig catalog columns. However, although that quoting rule looks a lot like SQL-identifier double quotes, there are two critical differences: empty strings ("") are legal, and depending on which variable you're considering, values longer than NAMEDATALEN might be valid too. So the current technique fails altogether on empty-string list entries (as reported by Steven Winfield in bug #15248) and it also risks truncating file pathnames during dump/reload of GUC values that are lists of pathnames. To fix, split the stored value without any downcasing or truncation, and then emit each element as a SQL string literal. This is a tad annoying, because we now have three copies of the comma-separated-string splitting logic in varlena.c as well as a fourth one in dumputils.c. (Not to mention the randomly-different-from-those splitting logic in libpq...) I looked at unifying these, but it would be rather a mess unless we're willing to tweak the API definitions of SplitIdentifierString, SplitDirectoriesString, or both. That might be worth doing in future; but it seems pretty unsafe for a back-patched bug fix, so for now accept the duplication. Back-patch to all supported branches, as the previous fix was. Discussion: https://postgr.es/m/7585.1529435872@sss.pgh.pa.us
* Document security implications of qualified names.Noah Misch2018-07-28
| | | | | | | | | | | Commit 5770172cb0c9df9e6ce27c507b449557e5b45124 documented secure schema usage, and that advice suffices for using unqualified names securely. Document, in typeconv-func primarily, the additional issues that arise with qualified names. Back-patch to 9.3 (all supported versions). Reviewed by Jonathan S. Katz. Discussion: https://postgr.es/m/20180721012446.GA1840594@rfd.leadboat.com
* Fix misc typos, mostly in comments.Heikki Linnakangas2018-07-18
| | | | | | | | A collection of typos I happened to spot while reading code, as well as grepping for common mistakes. Backpatch to all supported versions, as applicable, to avoid conflicts when backporting other commits in the future.
* Fix partial aggregation for variance(int4) and related aggregates.Tom Lane2018-06-21
| | | | | | | | | | | | | A typo in numeric_poly_combine caused bogus results for queries using it, but of course would only manifest if parallel aggregation is performed. Reported by Rajkumar Raghuwanshi. David Rowley did the diagnosis and the fix; I editorialized rather heavily on his regression test additions. Back-patch to v10 where the breakage was introduced (by 9cca11c91). Discussion: https://postgr.es/m/CAKcux6nU4E2x8nkSBpLOT2DPvQ5LviJ3SGyAN6Sz7qDH4G4+Pw@mail.gmail.com
* Accept TEXT and CDATA nodes in XMLTABLE's column_expression.Alvaro Herrera2018-06-20
| | | | | | | | | | | Column expressions that match TEXT or CDATA nodes must return the contents of the nodes themselves, not the content of non-existing children (i.e. the empty string). Author: Markus Winand Reported-by: Markus Winand Reviewed-by: Álvaro Herrera Discussion: https://postgr.es/m/0684A598-002C-42A2-AE12-F024A324EAE4@winand.at