summaryrefslogtreecommitdiff
path: root/src/backend/utils
AgeCommit message (Collapse)Author
2023-05-19pageinspect: Fix gist_page_items() with included columnsMichael Paquier
Non-leaf pages of GiST indexes contain key attributes, leaf pages contain both key and non-key attributes, and gist_page_items() ignored the handling of non-key attributes. This caused a few problems when using gist_page_items() on a GiST index with INCLUDE: - On a non-leaf page, the function would crash. - On a leaf page, the function would work, but miss to display all the values for included attributes. This commit fixes gist_page_items() to handle such cases in a more appropriate way, and now displays the values of key and non-key attributes for each item separately in a style consistent with what ruleutils.c would generate for the attribute list, depending on the page type dealt with. In a way similar to how a record is displayed, values would be double-quoted for key or non-key attributes if required. ruleutils.c did not provide a routine able to control if non-key attributes should be displayed, so an extended() routine for index definitions is added to work around the leaf and non-leaf page differences. While on it, this commit fixes a third problem related to the amount of data reported for key attributes. The code originally relied on BuildIndexValueDescription() (used for error reports on constraints) that would not print all the data stored in the index but the index opclass's input type, so this limited the amount of information available. This switch makes gist_page_items() much cheaper as there is no need to run ACL checks for each item printed, which is not an issue anyway as superuser rights are required to execute the functions of pageinspect. Opclasses whose data cannot be displayed can rely on gist_page_items_bytea(). The documentation of this function was slightly incorrect for the output results generated on HEAD and v15, so adjust it on these branches. Author: Alexander Lakhin, Michael Paquier Discussion: https://postgr.es/m/17884-cb8c326522977acb@postgresql.org Backpatch-through: 14
2023-05-04In array_position()/array_positions(), beware of empty input array.Tom Lane
These functions incautiously fetched the array's first lower bound even when the array is zero-dimensional, thus fetching the word after the allocated array space. While almost always harmless, with very bad luck this could result in SIGSEGV. Fix by adding an early exit for empty input. Per bug #17920 from Alexander Lakhin. Discussion: https://postgr.es/m/17920-f7c228c627b6d02e%40postgresql.org
2023-04-24Remove duplicate lines of codeDaniel Gustafsson
Commit 6df7a9698bb accidentally included two identical prototypes for default_multirange_selectivi() and commit 086cf1458c6 added a break; statement where one was already present, thus duplicating it. While there is no bug caused by this, fix by removing the duplicated lines as they provide no value. Backpatch the fix for duplicate prototypes to v14 and the duplicate break statement fix to all supported branches to avoid backpatching hazards due to the removal. Reported-by: Anton Voloshin <a.voloshin@postgrespro.ru> Discussion: https://postgr.es/m/0e69cb60-0176-f6d0-7e15-6478b7d85724@postgrespro.ru
2023-03-26Fix oversights in array manipulation.Tom Lane
The nested-arrays code path in ExecEvalArrayExpr() used palloc to allocate the result array, whereas every other array-creating function has used palloc0 since 18c0b4ecc. This mostly works, but unused bits past the end of the nulls bitmap may end up undefined. That causes valgrind complaints with -DWRITE_READ_PARSE_PLAN_TREES, and could cause planner misbehavior as cited in 18c0b4ecc. There seems no very good reason why we should strive to avoid palloc0 in just this one case, so fix it the easy way with s/palloc/palloc0/. While looking at that I noted that we also failed to check for overflow of "nbytes" and "nitems" while summing the sizes of the sub-arrays, potentially allowing a crash due to undersized output allocation. For "nbytes", follow the policy used by other array-munging code of checking for overflow after each addition. (As elsewhere, the last addition of the array's overhead space doesn't need an extra check, since palloc itself will catch a value between 1Gb and 2Gb.) For "nitems", there's no very good reason to sum the inputs at all, since we can perfectly well use ArrayGetNItems' result instead of ignoring it. Per discussion of this bug, also remove redundant zeroing of the nulls bitmap in array_set_element and array_set_slice. Patch by Alexander Lakhin and myself, per bug #17858 from Alexander Lakhin; thanks also to Richard Guo. These bugs are a dozen years old, so back-patch to all supported branches. Discussion: https://postgr.es/m/17858-8fd287fd3663d051@postgresql.org
2023-03-16Work around spurious compiler warning in inet operatorsAndres Freund
gcc 12+ has complaints like the following: ../../../../../pgsql/src/backend/utils/adt/network.c: In function 'inetnot': ../../../../../pgsql/src/backend/utils/adt/network.c:1893:34: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=] 1893 | pdst[nb] = ~pip[nb]; | ~~~~~~~~~^~~~~~~~~~ ../../../../../pgsql/src/include/utils/inet.h:27:23: note: at offset -1 into destination object 'ipaddr' of size 16 27 | unsigned char ipaddr[16]; /* up to 128 bits of address */ | ^~~~~~ ../../../../../pgsql/src/include/utils/inet.h:27:23: note: at offset -1 into destination object 'ipaddr' of size 16 This is due to a compiler bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104986 It has been a year since the bug has been reported without getting fixed. As the warnings are verbose and use of gcc 12 is becoming more common, it seems worth working around the bug. Particularly because a simple reformulation of the loop condition fixes the issue and isn't any less readable. Author: Tom Lane <tgl@sss.pgh.pa.us> Author: Andres Freund <andres@anarazel.de> Discussion: https://postgr.es/m/144536.1648326206@sss.pgh.pa.us Backpatch: 11-
2023-03-14Fix corner case bug in numeric to_char() some more.Tom Lane
The band-aid applied in commit f0bedf3e4 turns out to still need some work: it made sure we didn't set Np->last_relevant too small (to the left of the decimal point), but it didn't prevent setting it too large (off the end of the partially-converted string). This could result in fetching data beyond the end of the allocated space, which with very bad luck could cause a SIGSEGV, though I don't see any hazard of interesting memory disclosure. Per bug #17839 from Thiago Nunes. The bug's pretty ancient, so back-patch to all supported versions. Discussion: https://postgr.es/m/17839-aada50db24d7b0da@postgresql.org
2023-03-13Fix JSON error reporting for many cases of erroneous string values.Tom Lane
The majority of error exit cases in json_lex_string() failed to set lex->token_terminator, causing problems for the error context reporting code: it would see token_terminator less than token_start and do something more or less nuts. In v14 and up the end result could be as bad as a crash in report_json_context(). Older versions accidentally avoided that fate; but all versions produce error context lines that are far less useful than intended, because they'd stop at the end of the prior token instead of continuing to where the actually-bad input is. To fix, invent some macros that make it less notationally painful to do the right thing. Also add documentation about what the function is actually required to do; and in >= v14, add an assertion in report_json_context about token_terminator being sufficiently far advanced. Per report from Nikolay Shaplov. Back-patch to all supported versions. Discussion: https://postgr.es/m/7332649.x5DLKWyVIX@thinkpad-pgpro
2023-03-01Avoid fetching one past the end of translate()'s "to" parameter.Tom Lane
This is usually harmless, but if you were very unlucky it could provoke a segfault due to the "to" string being right up against the end of memory. Found via valgrind testing (so we might've found it earlier, except that our regression tests lacked any exercise of translate()'s deletion feature). Fix by switching the order of the test-for-end-of-string and advance-pointer steps. While here, compute "to_ptr + tolen" just once. (Smarter compilers might figure that out for themselves, but let's just make sure.) Report and fix by Daniil Anisimov, in bug #17816. Discussion: https://postgr.es/m/17816-70f3d2764e88a108@postgresql.org
2023-02-21Fix erroneous Valgrind markings in AllocSetRealloc.Tom Lane
If asked to decrease the size of a large (>8K) palloc chunk, AllocSetRealloc could improperly change the Valgrind state of memory beyond the new end of the chunk: it would mark data UNDEFINED as far as the old end of the chunk after having done the realloc(3) call, thus tromping on the state of memory that no longer belongs to it. One would normally expect that memory to now be marked NOACCESS, so that this mislabeling might prevent detection of later errors. If realloc() had chosen to move the chunk someplace else (unlikely, but well within its rights) we could also mismark perfectly-valid DEFINED data as UNDEFINED, causing false-positive valgrind reports later. Also, any malloc bookkeeping data placed within this area might now be wrongly marked, causing additional problems. Fix by replacing relevant uses of "oldsize" with "Min(size, oldsize)". It's sufficient to mark as far as "size" when that's smaller, because whatever remains in the new chunk size will be marked NOACCESS below, and we expect realloc() to have taken care of marking the memory beyond the new official end of the chunk. While we're here, also rename the function's "oldsize" variable to "oldchksize" to more clearly explain what it actually holds, namely the distance to the end of the chunk (that is, requested size plus trailing padding). This is more consistent with the use of "size" and "chksize" to hold the new requested size and chunk size. Add a new variable "oldsize" in the one stanza where we're actually talking about the old requested size. Oversight in commit c477f3e44. Back-patch to all supported branches, as that was, just in case anybody wants to do valgrind testing on back branches. Karina Litskevich Discussion: https://postgr.es/m/CACiT8iaAET-fmzjjZLjaJC4zwSJmrFyL7LAdHwaYyjjQOQ4hcg@mail.gmail.com
2023-02-17Print the correct aliases for DML target tables in ruleutils.Tom Lane
ruleutils.c blindly printed the user-given alias (or nothing if there hadn't been one) for the target table of INSERT/UPDATE/DELETE queries. That works a large percentage of the time, but not always: for queries appearing in WITH, it's possible that we chose a different alias to avoid conflict with outer-scope names. Since the chosen alias would be used in any Var references to the target table, this'd lead to an inconsistent printout with consequences such as dump/restore failures. The correct logic for printing (or not) a relation alias was embedded in get_from_clause_item. Factor it out to a separate function so that we don't need a jointree node to use it. (Only a limited part of that function can be reached from these new call sites, but this seems like the cleanest non-duplicative factorization.) In passing, I got rid of a redundant "\d+ rules_src" step in rules.sql. Initial report from Jonathan Katz; thanks to Vignesh C for analysis. This has been broken for a long time, so back-patch to all supported branches. Discussion: https://postgr.es/m/e947fa21-24b2-f922-375a-d4f763ef3e4b@postgresql.org Discussion: https://postgr.es/m/CALDaNm1MMntjmT_NJGp-Z=xbF02qHGAyuSHfYHias3TqQbPF2w@mail.gmail.com
2023-02-03Make int64_div_fast_to_numeric() more robust.Dean Rasheed
The prior coding of int64_div_fast_to_numeric() had a number of bugs that would cause it to fail under different circumstances, such as with log10val2 <= 0, or log10val2 a multiple of 4, or in the "slow" numeric path with log10val2 >= 10. None of those could be triggered by any of our current code, which only uses log10val2 = 3 or 6. However, they made it a hazard for any future code that might use it. Also, since this is exported by numeric.c, users writing their own C code might choose to use it. Therefore fix, and back-patch to v14, where it was introduced. Dean Rasheed, reviewed by Tom Lane. Discussion: https://postgr.es/m/CAEZATCW8gXgW0tgPxPgHDPhVX71%2BSWFRkhnXy%2BTfGDsKLepu2g%40mail.gmail.com
2023-01-26Fix rare sharedtuplestore.c corruption.Thomas Munro
If the final chunk of an oversized tuple being written out to disk was exactly 32760 bytes, it would be corrupted due to a fencepost bug. Bug #17619. Back-patch to 11 where the code arrived. While testing that (see test module in archives), I (tmunro) noticed that the per-participant page counter was not initialized to zero as it should have been; that wasn't a live bug when it was written since DSM memory was originally always zeroed, but since 14 min_dynamic_shared_memory might be configured and it supplies non-zeroed memory, so that is also fixed here. Author: Dmitry Astapov <dastapov@gmail.com> Discussion: https://postgr.es/m/17619-0de62ceda812b8b5%40postgresql.org
2023-01-19Add missing assign hook for GUC checkpoint_completion_targetMichael Paquier
This is wrong since 88e9823, that has switched the WAL sizing configuration from checkpoint_segments to min_wal_size and max_wal_size. This missed the recalculation of the internal value of the internal "CheckPointSegments", that works as a mapping of the old GUC checkpoint_segments, on reload, for example, and it controls the timing of checkpoints depending on the volume of WAL generated. Most users tend to leave checkpoint_completion_target at 0.9 to smooth the I/O workload, which is why I guess this has gone unnoticed for so long, still it can be useful to tweak and reload the value dynamically in some cases to control the timing of checkpoints. Author: Bharath Rupireddy Discussion: https://postgr.es/m/CALj2ACXgPPAm28mruojSBno+F_=9cTOOxHAywu_dfZPeBdybQw@mail.gmail.com Backpatch-through: 11
2023-01-12Fix jsonpath existense checking of missing variablesAlexander Korotkov
The current jsonpath code assumes that the referenced variable always exists. It could only throw an error at the value valuation time. At the same time existence checking assumes variable is present without valuation, and error suppression doesn't work for missing variables. This commit makes existense checking trigger an error for missing variables. This makes the overall behavior consistent. Backpatch to 12 where jsonpath was introduced. Reported-by: David G. Johnston Discussion: https://postgr.es/m/CAKFQuwbeytffJkVnEqDyLZ%3DrQsznoTh1OgDoOF3VmOMkxcTMjA%40mail.gmail.com Author: Alexander Korotkov, David G. Johnston Backpatch-through: 12
2023-01-03Fix typos in comments, code and documentationMichael Paquier
While on it, newlines are removed from the end of two elog() strings. The others are simple grammar mistakes. One comment in pg_upgrade referred incorrectly to sequences since a7e5457. Author: Justin Pryzby Discussion: https://postgr.es/m/20221230231257.GI1153@telsasoft.com Backpatch-through: 11
2022-12-12Fix jsonb subscripting to cope with toasted subscript values.Tom Lane
jsonb_get_element() was incautious enough to use VARDATA() and VARSIZE() directly on an arbitrary text Datum. That of course fails if the Datum is short-header, compressed, or out-of-line. The typical result would be failing to match any element of a jsonb object, though matching the wrong one seems possible as well. setPathObject() was slightly brighter, in that it used VARDATA_ANY and VARSIZE_ANY_EXHDR, but that only kept it out of trouble for short-header Datums. push_path() had the same issue. This could result in faulty subscripted insertions, though keys long enough to cause a problem are likely rare in the wild. Having seen these, I looked around for unsafe usages in the rest of the adt/json* files. There are a couple of places where it's not immediately obvious that the Datum can't be compressed or out-of-line, so I added pg_detoast_datum_packed() to cope if it is. Also, remove some other usages of VARDATA/VARSIZE on Datums we just extracted from a text array. Those aren't actively broken, but they will become so if we ever start allowing short-header array elements, which does not seem like a terribly unreasonable thing to do. In any case they are not great coding examples, and they could also do with comments pointing out that we're assuming we don't need pg_detoast_datum_packed. Per report from exe-dealer@yandex.ru. Patch by me, but thanks to David Johnston for initial investigation. Back-patch to v14 where jsonb subscripting was introduced. Discussion: https://postgr.es/m/205321670615953@mail.yandex.ru
2022-12-02Fix psql's \sf and \ef for new-style SQL functions.Tom Lane
Some options of these commands need to be able to identify the start of the function body within the output of pg_get_functiondef(). It used to be that that always began with "AS", but since the introduction of new-style SQL functions, it might also start with "BEGIN" or "RETURN". Fix that on the psql side, and add some regression tests. Noted by me awhile ago, but I didn't do anything about it. Thanks to David Johnston for a nag. Discussion: https://postgr.es/m/AM9PR01MB8268D5CDABDF044EE9F42173FE8C9@AM9PR01MB8268.eurprd01.prod.exchangelabs.com
2022-12-01Fix memory leak for hashing with nondeterministic collations.Jeff Davis
Backpatch through 12, where nondeterministic collations were introduced (5e1963fb76). Backpatch-through: 12
2022-12-01Fix under-parenthesized display of AT TIME ZONE constructs.Tom Lane
In commit 40c24bfef, I forgot to use get_rule_expr_paren() for the arguments of AT TIME ZONE, resulting in possibly not printing parens for expressions that need it. But get_rule_expr_paren() wouldn't have gotten it right anyway, because isSimpleNode() hadn't been taught that COERCE_SQL_SYNTAX parent nodes don't guarantee sufficient parentheses. Improve all that. Also use this methodology for F_IS_NORMALIZED, so that we don't print useless parens for that. In passing, remove a comment that was obsoleted later. Per report from Duncan Sands. Back-patch to v14 where this code came in. (Before that, we didn't try to print AT TIME ZONE that way, so there was no bug just ugliness.) Discussion: https://postgr.es/m/f41566aa-a057-6628-4b7c-b48770ecb84a@deepbluecap.com
2022-11-22YA attempt at taming worst-case behavior of get_actual_variable_range.Tom Lane
We've made multiple attempts at preventing get_actual_variable_range from taking an unreasonable amount of time (3ca930fc3, fccebe421). But there's still an issue for the very first planning attempt after deletion of a large number of extremal-valued tuples. While that planning attempt will set "killed" bits on the tuples it visits and thereby reduce effort for next time, there's still a lot of work it has to do to visit the heap and then set those bits. It's (usually?) not worth it to do that much work at plan time to have a slightly better estimate, especially in a context like this where the table contents are known to be mutating rapidly. Therefore, let's bound the amount of work to be done by giving up after we've visited 100 heap pages. Giving up just means we'll fall back on the extremal value recorded in pg_statistic, so it shouldn't mean that planner estimates suddenly become worthless. Note that this means we'll still gradually whittle down the problem by setting a few more index "killed" bits in each planning attempt; so eventually we'll reach a good state (barring further deletions), even in the absence of VACUUM. Simon Riggs, per a complaint from Jakub Wartak (with cosmetic adjustments by me). Back-patch to all supported branches. Discussion: https://postgr.es/m/CAKZiRmznOwi0oaV=4PHOCM4ygcH4MgSvt8=5cu_vNCfc8FSUug@mail.gmail.com
2022-11-21Add comments and a missing CHECK_FOR_INTERRUPTS in ts_headline.Tom Lane
I just spent an annoying amount of time reverse-engineering the 100%-undocumented API between ts_headline and the text search parser's prsheadline function. Add some commentary about that while it's fresh in mind. Also remove some unused macros in wparser_def.c. While at it, I noticed that when commit 78e73e875 added a CHECK_FOR_INTERRUPTS call in TS_execute_recurse, it missed doing so in the parallel function TS_phrase_execute, which surely needs one just as much. Back-patch because of the missing CHECK_FOR_INTERRUPTS. Might as well back-patch the rest of this too.
2022-10-16Fix EXPLAIN of SEARCH BREADTH FIRST with a constant initial value.Tom Lane
If the non-recursive term of a SEARCH BREADTH FIRST recursive query has only constants in its target list, the planner will fold the starting RowExpr added by rewrite into a simple Const of type RECORD. The executor doesn't have any problem with that --- but EXPLAIN VERBOSE will encounter the Const as the ultimate source of truth about what the field names of the SET column are, and it didn't know what to do with that. Fortunately, we can pull the identifying typmod out of the Const, in much the same way that record_out would. For reasons that remain a bit obscure to me, this only fails with SEARCH BREADTH FIRST, not SEARCH DEPTH FIRST or CYCLE. But I added regression test cases for both of those options too, just to make sure we don't break it in future. Per bug #17644 from Matthijs van der Vleuten. Back-patch to v14 where these constructs were added. Discussion: https://postgr.es/m/17644-3bd1f3036d6d7a16@postgresql.org
2022-09-28Change some errdetail() to errdetail_internal()Alvaro Herrera
This prevents marking the argument string for translation for gettext, and it also prevents the given string (which is already translated) from being translated at runtime. Also, mark the strings used as arguments to check_rolespec_name for translation. Backpatch all the way back as appropriate. None of this is caught by any tests (necessarily so), so I verified it manually.
2022-09-20Suppress variable-set-but-not-used warnings from clang 15.Tom Lane
clang 15+ will issue a set-but-not-used warning when the only use of a variable is in autoincrements (e.g., "foo++;"). That's perfectly sensible, but it detects a few more cases that we'd not noticed before. Silence the warnings with our usual methods, such as PG_USED_FOR_ASSERTS_ONLY, or in one case by actually removing a useless variable. One thing that we can't nicely get rid of is that with %pure-parser, Bison emits "yynerrs" as a local variable that falls foul of this warning. To silence those, I inserted "(void) yynerrs;" in the top-level productions of affected grammars. Per recently-established project policy, this is a candidate for back-patching into out-of-support branches: it suppresses annoying compiler warnings but changes no behavior. Hence, back-patch to 9.5, which is as far as these patches go without issues. (A preliminary check shows that the prior branches need some other set-but-not-used cleanups too, so I'll leave them for another day.) Discussion: https://postgr.es/m/514615.1663615243@sss.pgh.pa.us
2022-09-12Fix NaN comparison in circle_same testDaniel Gustafsson
Commit c4c340088 changed geometric operators to use float4 and float8 functions, and handle NaN's in a better way. The circle sameness test had a typo in the code which resulted in all comparisons with the left circle having a NaN radius considered same. postgres=# select '<(0,0),NaN>'::circle ~= '<(0,0),1>'::circle; ?column? ---------- t (1 row) This fixes the sameness test to consider the radius of both the left and right circle. Backpatch to v12 where this was introduced. Author: Ranier Vilela <ranier.vf@gmail.com> Discussion: https://postgr.es/m/CAEudQAo8dK=yctg2ZzjJuzV4zgOPBxRU5+Kb+yatFiddtQk6Rw@mail.gmail.com Backpatch-through: v12
2022-09-01Fix some possibly latent bugs in slab.cDavid Rowley
Primarily, this fixes an incorrect calculation in SlabCheck which was looking in the wrong byte for the sentinel check. The reason that we've never noticed this before in the form of a failing sentinel check is because the pre-check to this always fails because all current core users of slab contexts have a chunk size which is already MAXALIGNed, therefore there's never any space for the sentinel byte. It is possible that an extension needs to use a slab context and if they do with a chunk size that's not MAXALIGNed, then they'll likely get errors about overwritten sentinel bytes. Additionally, this patch changes various calculations which are being done based on the sizeof(SlabBlock). Currently, sizeof(SlabBlock) is a multiple of 8, therefore sizeof(SlabBlock) is the same as MAXALIGN(sizeof(SlabBlock)), however, if we were to ever have to add any fields to that struct as part of a bug fix, then SlabAlloc could end up returning a non-MAXALIGNed pointer. To be safe, let's ensure we always MAXALIGN sizeof(SlabBlock) before using it in any calculations. This patch has already been applied to master in d5ee4db0e. Diagnosed-by: Tomas Vondra, Tom Lane Author: Tomas Vondra, David Rowley Discussion: https://postgr.es/m/CAA4eK1%2B1JyW5TiL%3DyV-3Uq1CrfnTyn0Xrk5uArt31Z%3D8rgPhXQ%40mail.gmail.com Backpatch-through: 10
2022-08-24Defend against stack overrun in a few more places.Tom Lane
SplitToVariants() in the ispell code, lseg_inside_poly() in geo_ops.c, and regex_selectivity_sub() in selectivity estimation could recurse until stack overflow; fix by adding check_stack_depth() calls. So could next() in the regex compiler, but that case is better fixed by converting its tail recursion to a loop. (We probably get better code that way too, since next() can now be inlined into its sole caller.) There remains a reachable stack overrun in the Turkish stemmer, but we'll need some advice from the Snowball people about how to fix that. Per report from Egor Chindyaskin and Alexander Lakhin. These mistakes are old, so back-patch to all supported branches. Richard Guo and Tom Lane Discussion: https://postgr.es/m/1661334672.728714027@f473.i.mail.ru
2022-08-14Preserve memory context of VarStringSortSupport buffers.Tom Lane
When enlarging the work buffers of a VarStringSortSupport object, varstrfastcmp_locale was careful to keep them in the ssup_cxt memory context; but varstr_abbrev_convert just used palloc(). The latter creates a hazard that the buffers could be freed out from under the VarStringSortSupport object, resulting in stomping on whatever gets allocated in that memory later. In practice, because we only use this code for ICU collations (cf. 3df9c374e), the problem is confined to use of ICU collations. I believe it may have been unreachable before the introduction of incremental sort, too, as traditional sorting usually just uses one context for the duration of the sort. We could fix this by making the broken stanzas in varstr_abbrev_convert match the non-broken ones in varstrfastcmp_locale. However, it seems like a better idea to dodge the issue altogether by replacing the pfree-and-allocate-anew coding with repalloc, which automatically preserves the chunk's memory context. This fix does add a few cycles because repalloc will copy the chunk's content, which the existing coding assumes is useless. However, we don't expect that these buffer enlargement operations are performance-critical. Besides that, it's far from obvious that copying the buffer contents isn't required, since these stanzas make no effort to mark the buffers invalid by resetting last_returned, cache_blob, etc. That seems to be safe upon examination, but it's fragile and could easily get broken in future, which wouldn't get revealed in testing with short-to-moderate-size strings. Per bug #17584 from James Inform. Whether or not the issue is reachable in the older branches, this code has been broken on its own terms from its introduction, so patch all the way back. Discussion: https://postgr.es/m/17584-95c79b4a7d771f44@postgresql.org
2022-07-31Fix trim_array() for zero-dimensional array argument.Tom Lane
The code tried to access ARR_DIMS(v)[0] and ARR_LBOUND(v)[0] whether or not those values exist. This made the range check on the "n" argument unstable --- it might or might not fail, and if it did it would report garbage for the allowed upper limit. These bogus accesses would probably annoy Valgrind, and if you were very unlucky even lead to SIGSEGV. Report and fix by Martin Kalcher. Back-patch to v14 where this function was added. Discussion: https://postgr.es/m/baaeb413-b8a8-4656-5757-ef347e5ec11f@aboutsource.net
2022-07-27Allow "in place" tablespaces.Alvaro Herrera
This is a backpatch to branches 10-14 of the following commits: 7170f2159fb2 Allow "in place" tablespaces. c6f2f01611d4 Fix pg_basebackup with in-place tablespaces. f6f0db4d6240 Fix pg_tablespace_location() with in-place tablespaces 7a7cd84893e0 doc: Remove mention to in-place tablespaces for pg_tablespace_location() 5344723755bd Remove unnecessary Windows-specific basebackup code. In-place tablespaces were introduced as a testing helper mechanism, but they are going to be used for a bugfix in WAL replay to be backpatched to all stable branches. I (Álvaro) had to adjust some code to account for lack of get_dirent_type() in branches prior to 14. Author: Thomas Munro <thomas.munro@gmail.com> Author: Michaël Paquier <michael@paquier.xyz> Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/20220722081858.omhn2in5zt3g4nek@alvherre.pgsql
2022-07-21Fix ruleutils issues with dropped cols in functions-returning-composite.Tom Lane
Due to lack of concern for the case in the dependency code, it's possible to drop a column of a composite type even though stored queries have references to the dropped column via functions-in-FROM that return the composite type. There are "soft" references, namely FROM-clause aliases for such columns, and "hard" references, that is actual Vars referring to them. The right fix for hard references is to add dependencies preventing the drop; something we've known for many years and not done (and this commit still doesn't address it). A "soft" reference shouldn't prevent a drop though. We've been around on this before (cf. 9b35ddce9, 2c4debbd0), but nobody had noticed that the current behavior can result in dump/reload failures, because ruleutils.c can print more column aliases than the underlying composite type now has. So we need to rejigger the column-alias-handling code to treat such columns as dropped and not print aliases for them. Rather than writing new code for this, I used expandRTE() which already knows how to figure out which function result columns are dropped. I'd initially thought maybe we could use expandRTE() in all cases, but that fails for EXPLAIN's purposes, because the planner strips a lot of RTE infrastructure that expandRTE() needs. So this patch just uses it for unplanned function RTEs and otherwise does things the old way. If there is a hard reference (Var), then removing the column alias causes us to fail to print the Var, since there's no longer a name to print. Failing seems less desirable than printing a made-up name, so I made it print "?dropped?column?" instead. Per report from Timo Stolz. Back-patch to all supported branches. Discussion: https://postgr.es/m/5c91267e-3b6d-5795-189c-d15a55d61dbb@nullachtvierzehn.de
2022-07-17Fix omissions in support for the "regcollation" type.Tom Lane
The patch that added regcollation doesn't seem to have been too thorough about supporting it everywhere that other reg* types are supported. Fix that. (The find_expr_references omission is moderately serious, since it could result in missing expression dependencies. The others are less exciting.) Noted while fixing bug #17483. Back-patch to v13 where regcollation was added. Discussion: https://postgr.es/m/1423433.1652722406@sss.pgh.pa.us
2022-07-12Invent qsort_interruptible().Tom Lane
Justin Pryzby reported that some scenarios could cause gathering of extended statistics to spend many seconds in an un-cancelable qsort() operation. To fix, invent qsort_interruptible(), which is just like qsort_arg() except that it will also do CHECK_FOR_INTERRUPTS every so often. This bloats the backend by a couple of kB, which seems like a good investment. (We considered just enabling CHECK_FOR_INTERRUPTS in the existing qsort and qsort_arg functions, but there are some callers for which that'd demonstrably be unsafe. Opt-in seems like a better way.) For now, just apply qsort_interruptible() in statistics collection. There's probably more places where it could be useful, but we can always change other call sites as we find problems. Back-patch to v14. Before that we didn't have extended stats on expressions, so that the problem was less severe. Also, this patch depends on the sort_template infrastructure introduced in v14. Tom Lane and Justin Pryzby Discussion: https://postgr.es/m/20220509000108.GQ28830@telsasoft.com
2022-07-03Remove %error-verbose directive from jsonpath parserAndrew Dunstan
None of the other bison parsers contains this directive, and it gives rise to some unfortunate and impenetrable messages, so just remove it. Backpatch to release 12, where it was introduced. Per gripe from Erik Rijkers Discussion: https://postgr.es/m/ba069ce2-a98f-dc70-dc17-2ccf2a9bf7c7@xs4all.nl
2022-06-27Fix visibility check when XID is committed in CLOG but not in procarray.Heikki Linnakangas
TransactionIdIsInProgress had a fast path to return 'false' if the single-item CLOG cache said that the transaction was known to be committed. However, that was wrong, because a transaction is first marked as committed in the CLOG but doesn't become visible to others until it has removed its XID from the proc array. That could lead to an error: ERROR: t_xmin is uncommitted in tuple to be updated or for an UPDATE to go ahead without blocking, before the previous UPDATE on the same row was made visible. The window is usually very short, but synchronous replication makes it much wider, because the wait for synchronous replica happens in that window. Another thing that makes it hard to hit is that it's hard to get such a commit-in-progress transaction into the single item CLOG cache. Normally, if you call TransactionIdIsInProgress on such a transaction, it determines that the XID is in progress without checking the CLOG and without populating the cache. One way to prime the cache is to explicitly call pg_xact_status() on the XID. Another way is to use a lot of subtransactions, so that the subxid cache in the proc array is overflown, making TransactionIdIsInProgress rely on pg_subtrans and CLOG checks. This has been broken ever since it was introduced in 2008, but the race condition is very hard to hit, especially without synchronous replication. There were a couple of reports of the error starting from summer 2021, but no one was able to find the root cause then. TransactionIdIsKnownCompleted() is now unused. In 'master', remove it, but I left it in place in backbranches in case it's used by extensions. Also change pg_xact_status() to check TransactionIdIsInProgress(). Previously, it only checked the CLOG, and returned "committed" before the transaction was actually made visible to other queries. Note that this also means that you cannot use pg_xact_status() to reproduce the bug anymore, even if the code wasn't fixed. Report and analysis by Konstantin Knizhnik. Patch by Simon Riggs, with the pg_xact_status() change added by me. Author: Simon Riggs Reviewed-by: Andres Freund Discussion: https://www.postgresql.org/message-id/flat/4da7913d-398c-e2ad-d777-f752cf7f0bbb%40garret.ru
2022-06-27Fix relptr's encoding of the base address.Thomas Munro
Previously, we encoded both NULL and the first byte at the base address as 0. That confusion led to the assertion in commit e07d4ddc, which failed when min_dynamic_shared_memory was used. Give them distinct encodings, by switching to 1-based offsets for non-NULL pointers. Also improve macro hygiene in passing (missing/misplaced parentheses), and remove open-coded access to the raw offset value from freepage.c/h. Although e07d4ddc was back-patched to 10, the only code that actually makes use of relptr at the base address arrived in 84b1c63a, so no need to back-patch further than 14 for now. Reported-by: Justin Pryzby <pryzby@telsasoft.com> Reviewed-by: Robert Haas <robertmhaas@gmail.com> Discussion: https://postgr.es/m/20220519193839.GT19626%40telsasoft.com
2022-06-22Fix SPI's handling of errors during transaction commit.Tom Lane
SPI_commit previously left it up to the caller to recover from any error occurring during commit. Since that's complicated and requires use of low-level xact.c facilities, it's not too surprising that no caller got it right. Let's move the responsibility for cleanup into spi.c. Doing that requires redefining SPI_commit as starting a new transaction, so that it becomes equivalent to SPI_commit_and_chain except that you get default transaction characteristics instead of preserving the prior transaction's characteristics. We can make this pretty transparent API-wise by redefining SPI_start_transaction() as a no-op. Callers that expect to do something in between might be surprised, but available evidence is that no callers do so. Having made that API redefinition, we can fix this mess by having SPI_commit[_and_chain] trap errors and start a new, clean transaction before re-throwing the error. Likewise for SPI_rollback[_and_chain]. Some cleanup is also needed in AtEOXact_SPI, which was nowhere near smart enough to deal with SPI contexts nested inside a committing context. While plperl and pltcl need no changes beyond removing their now-useless SPI_start_transaction() calls, plpython needs some more work because it hadn't gotten the memo about catching commit/rollback errors in the first place. Such an error resulted in longjmp'ing out of the Python interpreter, which leaks Python stack entries at present and is reported to crash Python 3.11 altogether. Add the missing logic to catch such errors and convert them into Python exceptions. This is a back-patch of commit 2e517818f. That's now aged long enough to reduce the concerns about whether it will break something, and we do need to ensure that supported branches will work with Python 3.11. Peter Eisentraut and Tom Lane Discussion: https://postgr.es/m/3375ffd8-d71c-2565-e348-a597d6e739e3@enterprisedb.com Discussion: https://postgr.es/m/17416-ed8fe5d7213d6c25@postgresql.org
2022-05-31Ensure ParseTzFile() closes the input file after failing.Tom Lane
We hadn't noticed this because (a) few people feed invalid timezone abbreviation files to the server, and (b) in typical scenarios guc.c would throw ereport(ERROR) and then transaction abort handling would silently clean up the leaked file reference. However, it was possible to observe file leakage warnings if one breaks an already-active abbreviation file, because guc.c does not throw ERROR when loading supposedly-validated settings during session start or SIGHUP processing. Report and fix by Kyotaro Horiguchi (cosmetic adjustments by me) Discussion: https://postgr.es/m/20220530.173740.748502979257582392.horikyota.ntt@gmail.com
2022-05-28Handle NULL for short descriptions of custom GUC variablesMichael Paquier
If a short description is specified as NULL in one of the various DefineCustomXXXVariable() functions available to external modules to define a custom parameter, SHOW ALL would crash. This change teaches SHOW ALL to properly handle NULL short descriptions, as well as any code paths that manipulate it, to gain in flexibility. Note that help_config.c was already able to do that, when describing a set of GUCs for postgres --describe-config. Author: Steve Chavez Reviewed by: Nathan Bossart, Andres Freund, Michael Paquier, Tom Lane Discussion: https://postgr.es/m/CAGRrpzY6hO-Kmykna_XvsTv8P2DshGiU6G3j8yGao4mk0CqjHA%40mail.gmail.com Backpatch-through: 10
2022-05-21Show 'AS "?column?"' explicitly when it's important.Tom Lane
ruleutils.c was coded to suppress the AS label for a SELECT output expression if the column name is "?column?", which is the parser's fallback if it can't think of something better. This is fine, and avoids ugly clutter, so long as (1) nothing further up in the parse tree relies on that column name or (2) the same fallback would be assigned when the rule or view definition is reloaded. Unfortunately (2) is far from certain, both because ruleutils.c might print the expression in a different form from how it was originally written and because FigureColname's rules might change in future releases. So we shouldn't rely on that. Detecting exactly whether there is any outer-level use of a SELECT column name would be rather expensive. This patch takes the simpler approach of just passing down a flag indicating whether there *could* be any outer use; for example, the output column names of a SubLink are not referenceable, and we also do not care about the names exposed by the right-hand side of a setop. This is sufficient to suppress unwanted clutter in all but one case in the regression tests. That seems like reasonable evidence that it won't be too much in users' faces, while still fixing the cases we need to fix. Per bug #17486 from Nicolas Lutic. This issue is ancient, so back-patch to all supported branches. Discussion: https://postgr.es/m/17486-1ad6fd786728b8af@postgresql.org
2022-05-09Revert "Disallow infinite endpoints in generate_series() for timestamps."Tom Lane
This reverts commit eafdf9de06e9b60168f5e47cedcfceecdc6d4b5f and its back-branch counterparts. Corey Huinker pointed out that we'd discussed this exact change back in 2016 and rejected it, on the grounds that there's at least one usage pattern with LIMIT where an infinite endpoint can usefully be used. Perhaps that argument needs to be re-litigated, but there's no time left before our back-branch releases. To keep our options open, restore the status quo ante; if we do end up deciding to change things, waiting one more quarter won't hurt anything. Rather than just doing a straight revert, I added a new test case demonstrating the usage with LIMIT. That'll at least remind us of the issue if we forget again. Discussion: https://postgr.es/m/3603504.1652068977@sss.pgh.pa.us Discussion: https://postgr.es/m/CADkLM=dzw0Pvdqp5yWKxMd+VmNkAMhG=4ku7GnCZxebWnzmz3Q@mail.gmail.com
2022-05-09Make relation-enumerating operations be security-restricted operations.Noah Misch
When a feature enumerates relations and runs functions associated with all found relations, the feature's user shall not need to trust every user having permission to create objects. BRIN-specific functionality in autovacuum neglected to account for this, as did pg_amcheck and CLUSTER. 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. CREATE INDEX (not a relation-enumerating operation) and REINDEX protected themselves too late. This change extends to the non-enumerating amcheck interface. Back-patch to v10 (all supported versions). Sergey Shinderuk, reviewed (in earlier versions) by Alexander Lakhin. Reported by Alexander Lakhin. Security: CVE-2022-1552
2022-04-20Fix CLUSTER tuplesorts on abbreviated expressions.Peter Geoghegan
CLUSTER sort won't use the datum1 SortTuple field when clustering against an index whose leading key is an expression. This makes it unsafe to use the abbreviated keys optimization, which was missed by the logic that sets up SortSupport state. Affected tuplesorts output tuples in a completely bogus order as a result (the wrong SortSupport based comparator was used for the leading attribute). This issue is similar to the bug fixed on the master branch by recent commit cc58eecc5d. But it's a far older issue, that dates back to the introduction of the abbreviated keys optimization by commit 4ea51cdfe8. Backpatch to all supported versions. Author: Peter Geoghegan <pg@bowt.ie> Author: Thomas Munro <thomas.munro@gmail.com> Discussion: https://postgr.es/m/CA+hUKG+bA+bmwD36_oDxAoLrCwZjVtST2fqe=b4=qZcmU7u89A@mail.gmail.com Backpatch: 10-
2022-04-20Disallow infinite endpoints in generate_series() for timestamps.Tom Lane
Such cases will lead to infinite loops, so they're of no practical value. The numeric variant of generate_series() already threw error for this, so borrow its message wording. Per report from Richard Wesley. Back-patch to all supported branches. Discussion: https://postgr.es/m/91B44E7B-68D5-448F-95C8-B4B3B0F5DEAF@duckdblabs.com
2022-04-19Fix extract epoch from interval calculationPeter Eisentraut
The new numeric code for extract epoch from interval accidentally truncated the DAYS_PER_YEAR value to an integer, leading to results that mismatched the floating-point interval_part calculations. The commit a2da77cdb4661826482ebf2ddba1f953bc74afe4 that introduced this actually contains the regression test change that this reverts. I suppose this was missed at the time. Reported-by: Joseph Koshakow <koshy44@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/CAAvxfHd5n%3D13NYA2q_tUq%3D3%3DSuWU-CufmTf-Ozj%3DfrEgt7pXwQ%40mail.gmail.com
2022-03-27Fix NULL input behaviour of pg_stat_get_replication_slot().Andres Freund
pg_stat_get_replication_slot() accidentally was marked as non-strict, crashing when called with NULL input. As it's already released, introduce an explicit NULL check in 14, fix the catalog in HEAD. Bumps catversion in HEAD. Discussion: https://postgr.es/m/20220326212432.s5n2maw6kugnpyxw@alap3.anarazel.de Backpatch: 14-, where replication slot stats were introduced
2022-03-27Fix breakage of get_ps_display() in the PS_USE_NONE case.Tom Lane
Commit 8c6d30f21 caused this function to fail to set *displen in the PS_USE_NONE code path. If the variable's previous value had been negative, that'd lead to a memory clobber at some call sites. We'd managed not to notice due to very thin test coverage of such configurations, but this appears to explain buildfarm member lorikeet's recent struggles. Credit to Andrew Dunstan for spotting the problem. Back-patch to v13 where the bug was introduced. Discussion: https://postgr.es/m/136102.1648320427@sss.pgh.pa.us
2022-03-23Don't try to translate NULL in GetConfigOptionByNum().Andres Freund
Noticed via -fsanitize=undefined. Introduced when a few columns in GetConfigOptionByNum() / pg_settings started to be translated in 72be8c29a / PG 12. Backpatch to all affected branches, for the same reasons as 46ab07ffda9. Discussion: https://postgr.es/m/20220323173537.ll7klrglnp4gn2um@alap3.anarazel.de Backpatch: 12-
2022-03-23Don't call fwrite() with len == 0 when writing out relcache init file.Andres Freund
Noticed via -fsanitize=undefined. Backpatch to all branches, for the same reasons as 46ab07ffda9. Discussion: https://postgr.es/m/20220323173537.ll7klrglnp4gn2um@alap3.anarazel.de Backpatch: 10-
2022-03-21Fix assorted missing logic for GroupingFunc nodes.Tom Lane
The planner needs to treat GroupingFunc like Aggref for many purposes, in particular with respect to processing of the argument expressions, which are not to be evaluated at runtime. A few places hadn't gotten that memo, notably including subselect.c's processing of outer-level aggregates. This resulted in assertion failures or wrong plans for cases in which a GROUPING() construct references an outer aggregation level. Also fix missing special cases for GroupingFunc in cost_qual_eval (resulting in wrong cost estimates for GROUPING(), although it's not clear that that would affect plan shapes in practice) and in ruleutils.c (resulting in excess parentheses in pretty-print mode). Per bug #17088 from Yaoguang Chen. Back-patch to all supported branches. Richard Guo, Tom Lane Discussion: https://postgr.es/m/17088-e33882b387de7f5c@postgresql.org