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2021-07-31Fix corner-case errors and loss of precision in numeric_power().Dean Rasheed
This fixes a couple of related problems that arise when raising numbers to very large powers. Firstly, when raising a negative number to a very large integer power, the result should be well-defined, but the previous code would only cope if the exponent was small enough to go through power_var_int(). Otherwise it would throw an internal error, attempting to take the logarithm of a negative number. Fix this by adding suitable handling to the general case in power_var() to cope with negative bases, checking for integer powers there. Next, when raising a (positive or negative) number whose absolute value is slightly less than 1 to a very large power, the result should approach zero as the power is increased. However, in some cases, for sufficiently large powers, this would lose all precision and return 1 instead of 0. This was due to the way that the local_rscale was being calculated for the final full-precision calculation: local_rscale = rscale + (int) val - ln_dweight + 8 The first two terms on the right hand side are meant to give the number of significant digits required in the result ("val" being the estimated result weight). However, this failed to account for the fact that rscale is clipped to a maximum of NUMERIC_MAX_DISPLAY_SCALE (1000), and the result weight might be less then -1000, causing their sum to be negative, leading to a loss of precision. Fix this by forcing the number of significant digits calculated to be nonnegative. It's OK for it to be zero (when the result weight is less than -1000), since the local_rscale value then includes a few extra digits to ensure an accurate result. Finally, add additional underflow checks to exp_var() and power_var(), so that they consistently return zero for cases like this where the result is indistinguishable from zero. Some paths through this code already returned zero in such cases, but others were throwing overflow errors. Dean Rasheed, reviewed by Yugo Nagata. Discussion: http://postgr.es/m/CAEZATCW6Dvq7+3wN3tt5jLj-FyOcUgT5xNoOqce5=6Su0bCR0w@mail.gmail.com
2021-07-28Avoid using ambiguous word "non-negative" in error messages.Fujii Masao
The error messages using the word "non-negative" are confusing because it's ambiguous about whether it accepts zero or not. This commit improves those error messages by replacing it with less ambiguous word like "greater than zero" or "greater than or equal to zero". Also this commit added the note about the word "non-negative" to the error message style guide, to help writing the new error messages. When postgres_fdw option fetch_size was set to zero, previously the error message "fetch_size requires a non-negative integer value" was reported. This error message was outright buggy. Therefore back-patch to all supported versions where such buggy error message could be thrown. Reported-by: Hou Zhijie Author: Bharath Rupireddy Reviewed-by: Kyotaro Horiguchi, Fujii Masao Discussion: https://postgr.es/m/OS0PR01MB5716415335A06B489F1B3A8194569@OS0PR01MB5716.jpnprd01.prod.outlook.com
2021-07-10Fix numeric_mul() overflow due to too many digits after decimal point.Dean Rasheed
This fixes an overflow error when using the numeric * operator if the result has more than 16383 digits after the decimal point by rounding the result. Overflow errors should only occur if the result has too many digits *before* the decimal point. Discussion: https://postgr.es/m/CAEZATCUmeFWCrq2dNzZpRj5+6LfN85jYiDoqm+ucSXhb9U2TbA@mail.gmail.com
2021-07-09Add missing Int64GetDatum macro in dbsize.cDavid Rowley
I accidentally missed adding this when adjusting 55fe60938 for back patching. This adjustment was made for 9.6 to 13. 14 and master are not affected. Discussion: https://postgr.es/m/CAApHDvp=twCsGAGQG=A=cqOaj4mpknPBW-EZB-sd+5ZS5gCTtA@mail.gmail.com
2021-07-09Fix incorrect return value in pg_size_pretty(bigint)David Rowley
Due to how pg_size_pretty(bigint) was implemented, it's possible that when given a negative number of bytes that the returning value would not match the equivalent positive return value when given the equivalent positive number of bytes. This was due to two separate issues. 1. The function used bit shifting to convert the number of bytes into larger units. The rounding performed by bit shifting is not the same as dividing. For example -3 >> 1 = -2, but -3 / 2 = -1. These two operations are only equivalent with positive numbers. 2. The half_rounded() macro rounded towards positive infinity. This meant that negative numbers rounded towards zero and positive numbers rounded away from zero. Here we fix #1 by dividing the values instead of bit shifting. We fix #2 by adjusting the half_rounded macro always to round away from zero. Additionally, adjust the pg_size_pretty(numeric) function to be more explicit that it's using division rather than bit shifting. A casual observer might have believed bit shifting was used due to a static function being named numeric_shift_right. However, that function was calculating the divisor from the number of bits and performed division. Here we make that more clear. This change is just cosmetic and does not affect the return value of the numeric version of the function. Here we also add a set of regression tests both versions of pg_size_pretty() which test the values directly before and after the function switches to the next unit. This bug was introduced in 8a1fab36a. Prior to that negative values were always displayed in bytes. Author: Dean Rasheed, David Rowley Discussion: https://postgr.es/m/CAEZATCXnNW4HsmZnxhfezR5FuiGgp+mkY4AzcL5eRGO4fuadWg@mail.gmail.com Backpatch-through: 9.6, where the bug was introduced.
2021-06-12Ensure pg_filenode_relation(0, 0) returns NULL.Tom Lane
Previously, a zero value for the relfilenode resulted in a confusing error message about "unexpected duplicate". This function returns NULL for other invalid relfilenode values, so zero should be treated likewise. It's been like this all along, so back-patch to all supported branches. Justin Pryzby Discussion: https://postgr.es/m/20210612023324.GT16435@telsasoft.com
2021-06-01Reject SELECT ... GROUP BY GROUPING SETS (()) FOR UPDATE.Tom Lane
This case should be disallowed, just as FOR UPDATE with a plain GROUP BY is disallowed; FOR UPDATE only makes sense when each row of the query result can be identified with a single table row. However, we missed teaching CheckSelectLocking() to check groupingSets as well as groupClause, so that it would allow degenerate grouping sets. That resulted in a bad plan and a null-pointer dereference in the executor. Looking around for other instances of the same bug, the only one I found was in examine_simple_variable(). That'd just lead to silly estimates, but it should be fixed too. Per private report from Yaoguang Chen. Back-patch to all supported branches.
2021-05-10Prevent integer overflows in array subscripting calculations.Tom Lane
While we were (mostly) careful about ensuring that the dimensions of arrays aren't large enough to cause integer overflow, the lower bound values were generally not checked. This allows situations where lower_bound + dimension overflows an integer. It seems that that's harmless so far as array reading is concerned, except that array elements with subscripts notionally exceeding INT_MAX are inaccessible. However, it confuses various array-assignment logic, resulting in a potential for memory stomps. Fix by adding checks that array lower bounds aren't large enough to cause lower_bound + dimension to overflow. (Note: this results in disallowing cases where the last subscript position would be exactly INT_MAX. In principle we could probably allow that, but there's a lot of code that computes lower_bound + dimension and would need adjustment. It seems doubtful that it's worth the trouble/risk to allow it.) Somewhat independently of that, array_set_element() was careless about possible overflow when checking the subscript of a fixed-length array, creating a different route to memory stomps. Fix that too. Security: CVE-2021-32027
2021-04-12Fix out-of-bound memory access for interval -> char conversionMichael Paquier
Using Roman numbers (via "RM" or "rm") for a conversion to calculate a number of months has never considered the case of negative numbers, where a conversion could easily cause out-of-bound memory accesses. The conversions in themselves were not completely consistent either, as specifying 12 would result in NULL, but it should mean XII. This commit reworks the conversion calculation to have a more consistent behavior: - If the number of months and years is 0, return NULL. - If the number of months is positive, return the exact month number. - If the number of months is negative, do a backward calculation, with -1 meaning December, -2 November, etc. Reported-by: Theodor Arsenij Larionov-Trichkin Author: Julien Rouhaud Discussion: https://postgr.es/m/16953-f255a18f8c51f1d5@postgresql.org backpatch-through: 9.6
2021-02-12Avoid divide-by-zero in regex_selectivity() with long fixed prefix.Tom Lane
Given a regex pattern with a very long fixed prefix (approaching 500 characters), the result of pow(FIXED_CHAR_SEL, fixed_prefix_len) can underflow to zero. Typically the preceding selectivity calculation would have underflowed as well, so that we compute 0/0 and get NaN. In released branches this leads to an assertion failure later on. That doesn't happen in HEAD, for reasons I've not explored yet, but it's surely still a bug. To fix, just skip the division when the pow() result is zero, so that we'll (most likely) return a zero selectivity estimate. In the edge cases where "sel" didn't yet underflow, perhaps this isn't desirable, but I'm not sure that the case is worth spending a lot of effort on. The results of regex_selectivity_sub() are barely worth the electrons they're written on anyway :-( Per report from Alexander Lakhin. Back-patch to all supported versions. Discussion: https://postgr.es/m/6de0a0c3-ada9-cd0c-3e4e-2fa9964b41e3@gmail.com
2021-01-05Add an explicit cast to double when using fabs().Dean Rasheed
Commit bc43b7c2c0 used fabs() directly on an int variable, which apparently requires an explicit cast on some platforms. Per buildfarm.
2021-01-05Fix numeric_power() when the exponent is INT_MIN.Dean Rasheed
In power_var_int(), the computation of the number of significant digits to use in the computation used log(Abs(exp)), which isn't safe because Abs(exp) returns INT_MIN when exp is INT_MIN. Use fabs() instead of Abs(), so that the exponent is cast to a double before the absolute value is taken. Back-patch to 9.6, where this was introduced (by 7d9a4737c2). Discussion: https://postgr.es/m/CAEZATCVd6pMkz=BrZEgBKyqqJrt2xghr=fNc8+Z=5xC6cgWrWA@mail.gmail.com
2020-12-25Invalidate acl.c caches when pg_authid changes.Noah Misch
This makes existing sessions reflect "ALTER ROLE ... [NO]INHERIT" as quickly as they have been reflecting "GRANT role_name". Back-patch to 9.5 (all supported versions). Reviewed by Nathan Bossart. Discussion: https://postgr.es/m/20201221095028.GB3777719@rfd.leadboat.com
2020-12-21Remove "invalid concatenation of jsonb objects" error case.Tom Lane
The jsonb || jsonb operator arbitrarily rejected certain combinations of scalar and non-scalar inputs, while being willing to concatenate other combinations. This was of course quite undocumented. Rather than trying to document it, let's just remove the restriction, creating a uniform rule that unless we are handling an object-to-object concatenation, non-array inputs are converted to one-element arrays, resulting in an array-to-array concatenation. (This does not change the behavior for any case that didn't throw an error before.) Per complaint from Joel Jacobson. Back-patch to all supported branches. Discussion: https://postgr.es/m/163099.1608312033@sss.pgh.pa.us
2020-11-10Fix and simplify some usages of TimestampDifference().Tom Lane
Introduce TimestampDifferenceMilliseconds() to simplify callers that would rather have the difference in milliseconds, instead of the select()-oriented seconds-and-microseconds format. This gets rid of at least one integer division per call, and it eliminates some apparently-easy-to-mess-up arithmetic. Two of these call sites were in fact wrong: * pg_prewarm's autoprewarm_main() forgot to multiply the seconds by 1000, thus ending up with a delay 1000X shorter than intended. That doesn't quite make it a busy-wait, but close. * postgres_fdw's pgfdw_get_cleanup_result() thought it needed to compute microseconds not milliseconds, thus ending up with a delay 1000X longer than intended. Somebody along the way had noticed this problem but misdiagnosed the cause, and imposed an ad-hoc 60-second limit rather than fixing the units. This was relatively harmless in context, because we don't care that much about exactly how long this delay is; still, it's wrong. There are a few more callers of TimestampDifference() that don't have a direct need for seconds-and-microseconds, but can't use TimestampDifferenceMilliseconds() either because they do need microsecond precision or because they might possibly deal with intervals long enough to overflow 32-bit milliseconds. It might be worth inventing another API to improve that, but that seems outside the scope of this patch; so those callers are untouched here. Given the fact that we are fixing some bugs, and the likelihood that future patches might want to back-patch code that uses this new API, back-patch to all supported branches. Alexey Kondratov and Tom Lane Discussion: https://postgr.es/m/3b1c053a21c07c1ed5e00be3b2b855ef@postgrespro.ru
2020-09-30Fix handling of BC years in to_date/to_timestamp.Tom Lane
Previously, a conversion such as to_date('-44-02-01','YYYY-MM-DD') would result in '0045-02-01 BC', as the code attempted to interpret the negative year as BC, but failed to apply the correction needed for our internal handling of BC years. Fix the off-by-one problem. Also, arrange for the combination of a negative year and an explicit "BC" marker to cancel out and produce AD. This is how the negative-century case works, so it seems sane to do likewise. Continue to read "year 0000" as 1 BC. Oracle would throw an error, but we've accepted that case for a long time so I'm hesitant to change it in a back-patch. Per bug #16419 from Saeed Hubaishan. Back-patch to all supported branches. Dar Alathar-Yemen and Tom Lane Discussion: https://postgr.es/m/16419-d8d9db0a7553f01b@postgresql.org
2020-08-15Move new LOCKTAG_DATABASE_FROZEN_IDS to end of enum LockTagType.Noah Misch
Several PGXN modules reference LockTagType values; renumbering would force a recompile of those modules. Oversight in back-patch of today's commit 566372b3d6435639e4cc4476d79b8505a0297c87. Back-patch to released branches, v12 through 9.5. Reported by Tom Lane. Discussion: https://postgr.es/m/921383.1597523945@sss.pgh.pa.us
2020-08-15Prevent concurrent SimpleLruTruncate() for any given SLRU.Noah Misch
The SimpleLruTruncate() header comment states the new coding rule. To achieve this, add locktype "frozenid" and two LWLocks. This closes a rare opportunity for data loss, which manifested as "apparent wraparound" or "could not access status of transaction" errors. Data loss is more likely in pg_multixact, due to released branches' thin margin between multiStopLimit and multiWrapLimit. If a user's physical replication primary logged ": apparent wraparound" messages, the user should rebuild standbys of that primary regardless of symptoms. At less risk is a cluster having emitted "not accepting commands" errors or "must be vacuumed" warnings at some point. One can test a cluster for this data loss by running VACUUM FREEZE in every database. Back-patch to 9.5 (all supported versions). Discussion: https://postgr.es/m/20190218073103.GA1434723@rfd.leadboat.com
2020-07-31Fix recently-introduced performance problem in ts_headline().Tom Lane
The new hlCover() algorithm that I introduced in commit c9b0c678d turns out to potentially take O(N^2) or worse time on long documents, if there are many occurrences of individual query words but few or no substrings that actually satisfy the query. (One way to hit this behavior is with a "common_word & rare_word" type of query.) This seems unavoidable given the original goal of checking every substring of the document, so we have to back off that idea. Fortunately, it seems unlikely that anyone would really want headlines spanning all of a long document, so we can avoid the worse-than-linear behavior by imposing a maximum length of substring that we'll consider. For now, just hard-wire that maximum length as a multiple of max_words times max_fragments. Perhaps at some point somebody will argue for exposing it as a ts_headline parameter, but I'm hesitant to make such a feature addition in a back-patched bug fix. I also noted that the hlFirstIndex() function I'd added in that commit was unnecessarily stupid: it really only needs to check whether a HeadlineWordEntry's item pointer is null or not. This wouldn't make all that much difference in typical cases with queries having just a few terms, but a cycle shaved is a cycle earned. In addition, add a CHECK_FOR_INTERRUPTS call in TS_execute_recurse. This ensures that hlCover's loop is cancellable if it manages to take a long time, and it may protect some other TS_execute callers as well. Back-patch to 9.6 as the previous commit was. I also chose to add the CHECK_FOR_INTERRUPTS call to 9.5. The old hlCover() algorithm seems to avoid the O(N^2) behavior, at least on the test case I tried, but nonetheless it's not very quick on a long document. Per report from Stephen Frost. Discussion: https://postgr.es/m/20200724160535.GW12375@tamriel.snowman.net
2020-06-11Fix mishandling of NaN counts in numeric_[avg_]combine.Tom Lane
When merging two NumericAggStates, the code missed adding the new state's NaNcount unless its N was also nonzero; since those counts are independent, this is wrong. This would only have visible effect if some partial aggregate scans found only NaNs while earlier ones found only non-NaNs; then we could end up falsely deciding that there were no NaNs and fail to return a NaN final result as expected. That's pretty improbable, so it's no surprise this hasn't been reported from the field. Still, it's a bug. I didn't try to produce a regression test that would show the bug, but I did notice that these functions weren't being reached at all in our regression tests, so I improved the tests to at least exercise them. With these additions, I see pretty complete code coverage on the aggregation-related functions in numeric.c. Back-patch to 9.6 where this code was introduced. (I only added the improved test case as far back as v10, though, since the relevant part of aggregates.sql isn't there at all in 9.6.)
2020-06-01Fix use-after-release mistake in currtid() and currtid2() for viewsMichael Paquier
This issue has been present since the introduction of this code as of a3519a2 from 2002, and has been found by buildfarm member prion that uses RELCACHE_FORCE_RELEASE via the tests introduced recently in e786be5. Discussion: https://postgr.es/m/20200601022055.GB4121@paquier.xyz Backpatch-through: 9.5
2020-05-28Add CHECK_FOR_INTERRUPTS() to the repeat() functionJoe Conway
The repeat() function loops for potentially a long time without ever checking for interrupts. This prevents, for example, a query cancel from interrupting until the work is all done. Fix by inserting a CHECK_FOR_INTERRUPTS() into the loop. Backpatch to all supported versions. Discussion: https://www.postgresql.org/message-id/flat/8692553c-7fe8-17d9-cbc1-7cddb758f4c6%40joeconway.com
2020-05-14Fix the MSVC build for versions 2015 and later.Amit Kapila
Visual Studio 2015 and later versions should still be able to do the same as Visual Studio 2012, but the declaration of locale_name is missing in _locale_t, causing the code compilation to fail, hence this falls back instead on to enumerating all system locales by using EnumSystemLocalesEx to find the required locale name.  If the input argument is in Unix-style then we can get ISO Locale name directly by using GetLocaleInfoEx() with LCType as LOCALE_SNAME. In passing, change the documentation references of the now obsolete links. Note that this problem occurs only with NLS enabled builds. Author: Juan José Santamaría Flecha, Davinder Singh and Amit Kapila Reviewed-by: Ranier Vilela and Amit Kapila Backpatch-through: 9.5 Discussion: https://postgr.es/m/CAHzhFSFoJEWezR96um4-rg5W6m2Rj9Ud2CNZvV4NWc9tXV7aXQ@mail.gmail.com
2020-05-07Fix YA text phrase search bug.Tom Lane
checkcondition_str() failed to report multiple matches for a prefix pattern correctly: it would dutifully merge the match positions, but then after exiting that loop, if the last prefix-matching word had had no suitable positions, it would report there were no matches. The upshot would be failing to recognize a match that the query should match. It looks like you need all of these conditions to see the bug: * a phrase search (else we don't ask for match position details) * a prefix search item (else we don't get to this code) * a weight restriction (else checkclass_str won't fail) Noted while investigating a problem report from Pavel Borisov, though this is distinct from the issue he was on about. Back-patch to 9.6 where phrase search was added.
2020-05-01Get rid of trailing semicolons in C macro definitions.Tom Lane
Writing a trailing semicolon in a macro is almost never the right thing, because you almost always want to write a semicolon after each macro call instead. (Even if there was some reason to prefer not to, pgindent would probably make a hash of code formatted that way; so within PG the rule should basically be "don't do it".) Thus, if we have a semi inside the macro, the compiler sees "something;;". Much of the time the extra empty statement is harmless, but it could lead to mysterious syntax errors at call sites. In perhaps an overabundance of neatnik-ism, let's run around and get rid of the excess semicolons whereever possible. The only thing worse than a mysterious syntax error is a mysterious syntax error that only happens in the back branches; therefore, backpatch these changes where relevant, which is most of them because most of these mistakes are old. (The lack of reported problems shows that this is largely a hypothetical issue, but still, it could bite us in some future patch.) John Naylor and Tom Lane Discussion: https://postgr.es/m/CACPNZCs0qWTqJ2QUSGJ07B7uvAvzMb-KbG2q+oo+J3tsWN5cqw@mail.gmail.com
2020-04-27Fix full text search to handle NOT above a phrase search correctly.Tom Lane
Queries such as '!(foo<->bar)' failed to find matching rows when implemented as a GiST or GIN index search. That's because of failing to handle phrase searches as tri-valued when considering a query without any position information for the target tsvector. We can only say that the phrase operator might match, not that it does match; and therefore its NOT also might match. The previous coding incorrectly inverted the approximate phrase result to decide that there was certainly no match. To fix, we need to make TS_phrase_execute return a real ternary result, and then bubble that up accurately in TS_execute. As long as we have to do that anyway, we can simplify the baroque things TS_phrase_execute was doing internally to manage tri-valued searching with only a bool as explicit result. For now, I left the externally-visible result of TS_execute as a plain bool. There do not appear to be any outside callers that need to distinguish a three-way result, given that they passed in a flag saying what to do in the absence of position data. This might need to change someday, but we wouldn't want to back-patch such a change. Although tsginidx.c has its own TS_execute_ternary implementation for use at upper index levels, that sadly managed to get this case wrong as well :-(. Fixing it is a lot easier fortunately. Per bug #16388 from Charles Offenbacher. Back-patch to 9.6 where phrase search was introduced. Discussion: https://postgr.es/m/16388-98cffba38d0b7e6e@postgresql.org
2020-04-07Fix circle_in to accept "(x,y),r" as it's advertised to do.Tom Lane
Our documentation describes four allowed input syntaxes for circles, but the regression tests tried only three ... with predictable consequences. Remarkably, this has been wrong since the circle datatype was added in 1997, but nobody noticed till now. David Zhang, with some help from me Discussion: https://postgr.es/m/332c47fa-d951-7574-b5cc-a8f7f7201202@highgo.ca
2020-04-07Adjust bytea get_bit/set_bit to cope with bytea strings > 256MB.Tom Lane
Since the existing bit number argument can't exceed INT32_MAX, it's not possible for these functions to manipulate bits beyond the first 256MB of a bytea value. However, it'd be good if they could do at least that much, and not fall over entirely for longer bytea values. Adjust the comparisons to be done in int64 arithmetic so that works. Also tweak the error reports to show sane values in case of overflow. Also add some test cases to improve the miserable code coverage of these functions. Apply patch to back branches only; HEAD has a better solution as of commit 26a944cf2. Extracted from a much larger patch by Movead Li Discussion: https://postgr.es/m/20200312115135445367128@highgo.ca
2020-03-16Avoid holding a directory FD open across assorted SRF calls.Tom Lane
This extends the fixes made in commit 085b6b667 to other SRFs with the same bug, namely pg_logdir_ls(), pgrowlocks(), pg_timezone_names(), pg_ls_dir(), and pg_tablespace_databases(). Also adjust various comments and documentation to warn against expecting to clean up resources during a ValuePerCall SRF's final call. Back-patch to all supported branches, since these functions were all born broken. Justin Pryzby, with cosmetic tweaks by me Discussion: https://postgr.es/m/20200308173103.GC1357@telsasoft.com
2020-01-23Fix an oversight in commit 4c70098ff.Tom Lane
I had supposed that the from_char_seq_search() call sites were all passing the constant arrays you'd expect them to pass ... but on looking closer, the one for DY format was passing the days[] array not days_short[]. This accidentally worked because the day abbreviations in English are all the same as the first three letters of the full day names. However, once we took out the "maximum comparison length" logic, it stopped working. As penance for that oversight, add regression test cases covering this, as well as every other switch case in DCH_from_char() that was not reached according to the code coverage report. Also, fold the DCH_RM and DCH_rm cases into one --- now that seq_search is case independent, there's no need to pass different comparison arrays for those cases. Back-patch, as the previous commit was.
2020-01-23Clean up formatting.c's logic for matching constant strings.Tom Lane
seq_search(), which is used to match input substrings to constants such as month and day names, had a lot of bizarre and unnecessary behaviors. It was mostly possible to avert our eyes from that before, but we don't want to duplicate those behaviors in the upcoming patch to allow recognition of non-English month and day names. So it's time to clean this up. In particular: * seq_search scribbled on the input string, which is a pretty dangerous thing to do, especially in the badly underdocumented way it was done here. Fortunately the input string is a temporary copy, but that was being made three subroutine levels away, making it something easy to break accidentally. The behavior is externally visible nonetheless, in the form of odd case-folding in error reports about unrecognized month/day names. The scribbling is evidently being done to save a few calls to pg_tolower, but that's such a cheap function (at least for ASCII data) that it's pretty pointless to worry about. In HEAD I switched it to be pg_ascii_tolower to ensure it is cheap in all cases; but there are corner cases in Turkish where this'd change behavior, so leave it as pg_tolower in the back branches. * seq_search insisted on knowing the case form (all-upper, all-lower, or initcap) of the constant strings, so that it didn't have to case-fold them to perform case-insensitive comparisons. This likewise seems like excessive micro-optimization, given that pg_tolower is certainly very cheap for ASCII data. It seems unsafe to assume that we know the case form that will come out of pg_locale.c for localized month/day names, so it's better just to define the comparison rule as "downcase all strings before comparing". (The choice between downcasing and upcasing is arbitrary so far as English is concerned, but it might not be in other locales, so follow citext's lead here.) * seq_search also had a parameter that'd cause it to report a match after a maximum number of characters, even if the constant string were longer than that. This was not actually used because no caller passed a value small enough to cut off a comparison. Replicating that behavior for localized month/day names seems expensive as well as useless, so let's get rid of that too. * from_char_seq_search used the maximum-length parameter to truncate the input string in error reports about not finding a matching name. This leads to rather confusing reports in many cases. Worse, it is outright dangerous if the input string isn't all-ASCII, because we risk truncating the string in the middle of a multibyte character. That'd lead either to delivering an illegible error message to the client, or to encoding-conversion failures that obscure the actual data problem. Get rid of that in favor of truncating at whitespace if any (a suggestion due to Alvaro Herrera). In addition to fixing these things, I const-ified the input string pointers of DCH_from_char and its subroutines, to make sure there aren't any other scribbling-on-input problems. The risk of generating a badly-encoded error message seems like enough of a bug to justify back-patching, so patch all supported branches. Discussion: https://postgr.es/m/29432.1579731087@sss.pgh.pa.us
2020-01-12Fix edge-case crashes and misestimation in range containment selectivity.Tom Lane
When estimating the selectivity of "range_var <@ range_constant" or "range_var @> range_constant", if the upper (or respectively lower) bound of the range_constant was above the last bin of the range_var's histogram, the code would access uninitialized memory and potentially crash (though it seems the probability of a crash is quite low). Handle the endpoint cases explicitly to fix that. While at it, be more paranoid about the possibility of getting NaN or other silly results from the range type's subdiff function. And improve some comments. Ordinarily we'd probably add a regression test case demonstrating the bug in unpatched code. But it's too hard to get it to crash reliably because of the uninitialized-memory dependence, so skip that. Per bug #16122 from Adam Scott. It's been broken from the beginning, apparently, so backpatch to all supported branches. Diagnosis by Michael Paquier, patch by Andrey Borodin and Tom Lane. Discussion: https://postgr.es/m/16122-eb35bc248c806c15@postgresql.org
2019-12-12Fix EXTRACT(ISOYEAR FROM timestamp) for years BC.Tom Lane
The test cases added by commit 26ae3aa80 exposed an old oversight in timestamp[tz]_part: they didn't correct the result of date2isoyear() for BC years, so that we produced an off-by-one answer for such years. Fix that, and back-patch to all supported branches. Discussion: https://postgr.es/m/SG2PR06MB37762CAE45DB0F6CA7001EA9B6550@SG2PR06MB3776.apcprd06.prod.outlook.com
2019-12-12Remove redundant function calls in timestamp[tz]_part().Tom Lane
The DTK_DOW/DTK_ISODOW and DTK_DOY switch cases in timestamp_part() and timestamptz_part() contained calls of timestamp2tm() that were fully redundant with the ones done just above the switch. This evidently crept in during commit 258ee1b63, which relocated that code from another place where the calls were indeed needed. Just delete the redundant calls. I (tgl) noted that our test coverage of these functions left quite a bit to be desired, so extend timestamp.sql and timestamptz.sql to cover all the branches. Back-patch to all supported branches, as the previous commit was. There's no real issue here other than some wasted cycles in some not-too-heavily-used code paths, but the test coverage seems valuable. Report and patch by Li Japin; test case adjustments by me. Discussion: https://postgr.es/m/SG2PR06MB37762CAE45DB0F6CA7001EA9B6550@SG2PR06MB3776.apcprd06.prod.outlook.com
2019-11-21Defend against self-referential views in relation_is_updatable().Tom Lane
While a self-referential view doesn't actually work, it's possible to create one, and it turns out that this breaks some of the information_schema views. Those views call relation_is_updatable(), which neglected to consider the hazards of being recursive. In older PG versions you get a "stack depth limit exceeded" error, but since v10 it'd recurse to the point of stack overrun and crash, because commit a4c35ea1c took out the expression_returns_set() call that was incidentally checking the stack depth. Since this function is only used by information_schema views, it seems like it'd be better to return "not updatable" than suffer an error. Hence, add tracking of what views we're examining, in just the same way that the nearby fireRIRrules() code detects self-referential views. I added a check_stack_depth() call too, just to be defensive. Per private report from Manuel Rigger. Back-patch to all supported versions.
2019-11-16Further fix dumping of views that contain just VALUES(...).Tom Lane
It turns out that commit e9f1c01b7 missed a case: we must print a VALUES clause in long format if get_query_def is given a resultDesc that would require the query's output column name(s) to be different from what the bare VALUES clause would produce. This applies in case an ALTER ... RENAME COLUMN has been done to a view that formerly could be printed in simple format, as shown in the added regression test case. It also explains bug #16119 from Dmitry Telpt, because it turns out that (unlike CREATE VIEW) CREATE MATERIALIZED VIEW fails to apply any column aliases it's given to the stored ON SELECT rule. So to get them to be printed, we have to account for the resultDesc renaming. It might be worth changing the matview code so that it creates the ON SELECT rule with the correct aliases; but we'd still need these messy checks in get_simple_values_rte to handle the case of a subsequent column rename, so any such change would be just neatnik-ism not a bug fix. Like the previous patch, back-patch to all supported branches. Discussion: https://postgr.es/m/16119-e64823f30a45a754@postgresql.org
2019-11-07Fix integer-overflow edge case detection in interval_mul and pgbench.Tom Lane
This patch adopts the overflow check logic introduced by commit cbdb8b4c0 into two more places. interval_mul() failed to notice if it computed a new microseconds value that was one more than INT64_MAX, and pgbench's double-to-int64 logic had the same sorts of edge-case problems that cbdb8b4c0 fixed in the core code. To make this easier to get right in future, put the guts of the checks into new macros in c.h, and add commentary about how to use the macros correctly. Back-patch to all supported branches, as we did with the previous fix. Yuya Watari Discussion: https://postgr.es/m/CAJ2pMkbkkFw2hb9Qb1Zj8d06EhWAQXFLy73St4qWv6aX=vqnjw@mail.gmail.com
2019-11-04Catch invalid typlens in a couple of placesPeter Eisentraut
Rearrange the logic in record_image_cmp() and record_image_eq() to error out on unexpected typlens (either not supported there or completely invalid due to corruption). Barring corruption, this is not possible today but it seems more future-proof and robust to fix this. Reported-by: Peter Geoghegan <pg@bowt.ie>
2019-10-04Fix bitshiftright()'s zero-padding some more.Tom Lane
Commit 5ac0d9360 failed to entirely fix bitshiftright's habit of leaving one-bits in the pad space that should be all zeroes, because in a moment of sheer brain fade I'd concluded that only the code path used for not-a-multiple-of-8 shift distances needed to be fixed. Of course, a multiple-of-8 shift distance can also cause the problem, so we need to forcibly zero the extra bits in both cases. Per bug #16037 from Alexander Lakhin. As before, back-patch to all supported branches. Discussion: https://postgr.es/m/16037-1d1ebca564db54f4@postgresql.org
2019-09-22Fix failure to zero-pad the result of bitshiftright().Tom Lane
If the bitstring length is not a multiple of 8, we'd shift the rightmost bits into the pad space, which must be zeroes --- bit_cmp, for one, depends on that. This'd lead to the result failing to compare equal to what it should compare equal to, as reported in bug #16013 from Daryl Waycott. This is, if memory serves, not the first such bug in the bitstring functions. In hopes of making it the last one, do a bit more work than minimally necessary to fix the bug: * Add assertion checks to bit_out() and varbit_out() to complain if they are given incorrectly-padded input. This will improve the odds that manual testing of any new patch finds problems. * Encapsulate the padding-related logic in macros to make it easier to use. Also, remove unnecessary padding logic from bit_or() and bitxor(). Somebody had already noted that we need not re-pad the result of bit_and() since the inputs are required to be the same length, but failed to extrapolate that to the other two. Also, move a comment block that once was near the head of varbit.c (but people kept putting other stuff in front of it), to put it in the header block. Note for the release notes: if anyone has inconsistent data as a result of saving the output of bitshiftright() in a table, it's possible to fix it with something like UPDATE mytab SET bitcol = ~(~bitcol) WHERE bitcol != ~(~bitcol); This has been broken since day one, so back-patch to all supported branches. Discussion: https://postgr.es/m/16013-c2765b6996aacae9@postgresql.org
2019-08-07Fix some incorrect parsing of time with time zone stringsMichael Paquier
When parsing a timetz string with a dynamic timezone abbreviation or a timezone not specified, it was possible to generate incorrect timestamps based on a date which uses some non-initialized variables if the input string did not specify fully a date to parse. This is already checked when a full timezone spec is included in the input string, but the two other cases mentioned above missed the same checks. This gets fixed by generating an error as this input is invalid, or in short when a date is not fully specified. Valgrind was complaining about this problem. Bug: #15910 Author: Alexander Lakhin Discussion: https://postgr.es/m/15910-2eba5106b9aa0c61@postgresql.org Backpatch-through: 9.4
2019-08-05Require the schema qualification in pg_temp.type_name(arg).Noah Misch
Commit aa27977fe21a7dfa4da4376ad66ae37cb8f0d0b5 introduced this restriction for pg_temp.function_name(arg); do likewise for types created in temporary schemas. Programs that this breaks should add "pg_temp." schema qualification or switch to arg::type_name syntax. Back-patch to 9.4 (all supported versions). Reviewed by Tom Lane. Reported by Tom Lane. Security: CVE-2019-10208
2019-07-26Tweak our special-case logic for the IANA "Factory" timezone.Tom Lane
pg_timezone_names() tries to avoid showing the "Factory" zone in the view, mainly because that has traditionally had a very long "abbreviation" such as "Local time zone must be set--see zic manual page", so that showing it messes up psql's formatting of the whole view. Since tzdb version 2016g, IANA instead uses the abbreviation "-00", which is sane enough that there's no reason to discriminate against it. On the other hand, it emerges that FreeBSD and possibly other packagers are so wedded to backwards compatibility that they hack the IANA data to keep the old spelling --- and not just that old spelling, but even older spellings that IANA used back in the stone age. This caused the filter logic to fail to suppress "Factory" at all on such platforms, though the formatting problem is definitely real in that case. To solve both problems, get rid of the hard-wired assumption about exactly what Factory's abbreviation is, and instead reject abbreviations exceeding 31 characters. This will allow Factory to appear in the view if and only if it's using the modern abbreviation. In passing, simplify the code we add to zic.c to support "zic -P" to remove its now-obsolete hacks to not print the Factory zone's abbreviation. Unlike pg_timezone_names(), there's no reason for that code to support old/nonstandard timezone data. Since we generally prefer to keep timezone-related behavior the same in all branches, and since this is arguably a bug fix, back-patch to all supported branches. Discussion: https://postgr.es/m/3961.1564086915@sss.pgh.pa.us
2019-07-26Fix loss of fractional digits for large values in cash_numeric().Tom Lane
Money values exceeding about 18 digits (depending on lc_monetary) could be inaccurately converted to numeric, due to select_div_scale() deciding it didn't need to compute any fractional digits. Force its hand by setting the dscale of one division input to equal the number of fractional digits we need. In passing, rearrange the logic to not do useless work in locales where money values are considered integral. Per bug #15925 from Slawomir Chodnicki. Back-patch to all supported branches. Discussion: https://postgr.es/m/15925-da9953e2674bb5c8@postgresql.org
2019-07-18Fix error in commit e6feef57.Jeff Davis
I was careless passing a datum directly to DATE_NOT_FINITE without calling DatumGetDateADT() first. Backpatch-through: 9.4
2019-07-18Fix daterange canonicalization for +/- infinity.Jeff Davis
The values 'infinity' and '-infinity' are a part of the DATE type itself, so a bound of the date 'infinity' is not the same as an unbounded/infinite range. However, it is still wrong to try to canonicalize such values, because adding or subtracting one has no effect. Fix by treating 'infinity' and '-infinity' the same as unbounded ranges for the purposes of canonicalization (but not other purposes). Backpatch to all versions because it is inconsistent with the documented behavior. Note that this could be an incompatibility for applications relying on the behavior contrary to the documentation. Author: Laurenz Albe Reviewed-by: Thomas Munro Discussion: https://postgr.es/m/77f24ea19ab802bc9bc60ddbb8977ee2d646aec1.camel%40cybertec.at Backpatch-through: 9.4
2019-06-30Don't read fields of a misaligned ExpandedObjectHeader or AnyArrayType.Noah Misch
UBSan complains about this. Instead, cast to a suitable type requiring only 4-byte alignment. DatumGetAnyArrayP() already assumes one can cast between AnyArrayType and ArrayType, so this doesn't introduce a new assumption. Back-patch to 9.5, where AnyArrayType was introduced. Reviewed by Tom Lane. Discussion: https://postgr.es/m/20190629210334.GA1244217@rfd.leadboat.com
2019-06-12Fix incorrect printing of queries with duplicated join names.Tom Lane
Given a query in which multiple JOIN nodes used the same alias (which'd necessarily be in different sub-SELECTs), ruleutils.c would assign the JOIN nodes distinct aliases for clarity ... but then it forgot to print the modified aliases when dumping the JOIN nodes themselves. This results in a dump/reload hazard for views, because the emitted query is flat-out incorrect: Vars will be printed with table names that have no referent. This has been wrong for a long time, so back-patch to all supported branches. Philip Dubé Discussion: https://postgr.es/m/CY4PR2101MB080246F2955FF58A6ED1FEAC98140@CY4PR2101MB0802.namprd21.prod.outlook.com
2019-05-06Use checkAsUser for selectivity estimator checks, if it's set.Dean Rasheed
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.
2019-05-06Fix security checks for selectivity estimation functions with RLS.Dean Rasheed
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