Recent releases had a check on rel->rd_refcnt in heap_drop_with_catalog,
but failed to cover the possibility of pending trigger events at DROP time.
(Before 8.4 we didn't even check the refcnt.) When the trigger events were
eventually fired, you'd get "could not open relation with OID nnn" errors,
as in recent report from strk. Better to throw a suitable error when the
DROP is attempted.
Also add a similar check in DROP INDEX.
Back-patch to all supported branches.
New versions of libintl redefine setlocale() to a macro
which causes problems when the backend and libintl are
linked against different versions of the runtime, which
is often the case in msvc builds.
Hiroshi Inoue, slightly updated comment by me
reduce_outer_joins() mistakenly treated a semijoin like a left join for
purposes of deciding whether not-null constraints created by the join's
quals could be passed down into the join's left-hand side (possibly
resulting in outer-join simplification there). Actually, semijoin works
like inner join for this purpose, ie, we do not need to see any rows that
can't possibly satisfy the quals. Hence, two-line fix to treat semi and
inner joins alike. Per observation by Andres Freund about a performance
gripe from Yazan Suleiman.
Back-patch to 8.4, since this oversight has been there since the current
handling of semijoins was implemented.
contrib/intarray's gettoken() uses a fixed-size buffer to collect an
integer's digits, and did not guard against overrunning the buffer.
This is at least a backend crash risk, and in principle might allow
arbitrary code execution. The code didn't check for overflow of the
integer value either, which while not presenting a crash risk was still
bad.
Thanks to Apple Inc's security team for reporting this issue and supplying
the fix.
Security: CVE-2010-4015
We only need that header when compiling with icc, since the gcc variant of
ia64_get_bsp() uses in-line assembly code. Per report from Frank Brendel,
the header doesn't exist on all IA64 platforms; so don't include it unless
we need it.
Specifically, this makes the workflow pg_dump -Fc -> pg_restore -> file
produce correct output for BLOBs when the source database has
standard_conforming_strings turned on. It was already okay when that was
off, or if pg_restore was told to restore directly into a database.
This is a back-port of commit b1732111f2 of
2009-08-04, with additional changes to emit old-style escaped bytea data
instead of hex-style. At the time, we had not heard of anyone encountering
the problem in the field, so I judged it not worth the risk of changing
back branches. Now we do have a report, from Bosco Rama, so back-patch
into 8.2 through 8.4. 9.0 and up are okay already.
If the slice to be assigned to was before the existing array lower bound
(requiring at least one null element to spring into existence to fill the
gap), the code miscalculated how many entries needed to be copied from
the old array's null bitmap. This could result in trashing the array's
data area (as seen in bug #5840 from Karsten Loesing), or worse.
This has been broken since we first allowed the behavior of assigning to
non-adjacent slices, in 8.2. Back-patch to all affected versions.
The "date" type supports a wider range of dates than int64 timestamps do.
However, there is pre-int64-timestamp code in the planner that assumes that
all date values can be converted to timestamp with impunity. Fortunately,
what we really need out of the conversion is always a double (float8)
value; so even when the date is out of timestamp's range it's possible to
produce a sane answer. All we need is a code path that doesn't try to
force the result into int64. Per trouble report from David Rericha.
Back-patch to all supported versions. Although this is surely a corner
case, there's not much point in advertising a date range wider than
timestamp's if we will choke on such values in unexpected places.
eval_const_expressions() can replace CaseTestExprs with constants when
the surrounding CASE's test expression is a constant. This confuses
ruleutils.c's heuristic for deparsing simple-form CASEs, leading to
Assert failures or "unexpected CASE WHEN clause" errors. I had put in
a hack solution for that years ago (see commit
514ce7a331 of 2006-10-01), but bug #5794
from Peter Speck shows that that solution failed to cover all cases.
Fortunately, there's a much better way, which came to me upon reflecting
that Peter's "CASE TRUE WHEN" seemed pretty redundant: we can "simplify"
the simple-form CASE to the general form of CASE, by simply omitting the
constant test expression from the rebuilt CASE construct. This is
intuitively valid because there is no need for the executor to evaluate
the test expression at runtime; it will never be referenced, because any
CaseTestExprs that would have referenced it are now replaced by constants.
This won't save a whole lot of cycles, since evaluating a Const is pretty
cheap, but a cycle saved is a cycle earned. In any case it beats kluging
ruleutils.c still further. So this patch improves const-simplification
and reverts the previous change in ruleutils.c.
Back-patch to all supported branches. The bug exists in 8.1 too, but it's
out of warranty.
After parsing a parenthesized subexpression, we must pop all pending
ANDs and NOTs off the stack, just like the case for a simple operand.
Per bug #5793.
Also fix clones of this routine in contrib/intarray and contrib/ltree,
where input of types query_int and ltxtquery had the same problem.
Back-patch to all supported versions.
We don't actually need optreset, because we can easily fix the code to
ensure that it's cleanly restartable after having completed a scan over the
argv array; which is the only case we need to restart in. Getting rid of
it avoids a class of interactions with the system libraries and allows
reversion of my change of yesterday in postmaster.c and postgres.c.
Back-patch to 8.4. Before that the getopt code was a bit different anyway.
The mingw people don't appear to care about compatibility with non-GNU
versions of getopt, so force use of our own copy of getopt on Windows.
Also, ensure that we make use of optreset when using our own copy.
Per report from Andrew Dunstan. Back-patch to all versions supported
on Windows.
Fix the same size_alpha versus size_beta typo that was recently fixed
in contrib/cube. Noted by Alexander Korotkov.
Back-patch to all supported branches (there is a more invasive fix in
HEAD).
The original coding in tuplestore_trim() was only meant to work efficiently
in cases where each trim call deleted most of the tuples in the store.
Which, in fact, was the pattern of the original usage with a Material node
supporting mark/restore operations underneath a MergeJoin. However,
WindowAgg now uses tuplestores and it has considerably less friendly
trimming behavior. In particular it can attempt to trim one tuple at a
time off a large tuplestore. tuplestore_trim() had O(N^2) runtime in this
situation because of repeatedly shifting its tuple pointer array. Fix by
avoiding shifting the array until a reasonably large number of tuples have
been deleted. This can waste some pointer space, but we do still reclaim
the tuples themselves, so the percentage wastage should be pretty small.
Per Jie Li's report of slow percent_rank() evaluation. cume_dist() and
ntile() would certainly be affected as well, along with any other window
function that has a moving frame start and requires reading substantially
ahead of the current row.
Back-patch to 8.4, where window functions were introduced. There's no
need to tweak it before that.
Recent versions of the Linux system header files cause xlogdefs.h to
believe that open_datasync should be the default sync method, whereas
formerly fdatasync was the default on Linux. open_datasync is a bad
choice, first because it doesn't actually outperform fdatasync (in fact
the reverse), and second because we try to use O_DIRECT with it, causing
failures on certain filesystems (e.g., ext4 with data=journal option).
This part of the patch is largely per a proposal from Marti Raudsepp.
More extensive changes are likely to follow in HEAD, but this is as much
change as we want to back-patch.
Also clean up confusing code and incorrect documentation surrounding the
fsync_writethrough option. Those changes shouldn't result in any actual
behavioral change, but I chose to back-patch them anyway to keep the
branches looking similar in this area.
In 9.0 and HEAD, also do some copy-editing on the WAL Reliability
documentation section.
Back-patch to all supported branches, since any of them might get used
on modern Linux versions.
There are some code paths, such as SPI_execute(), where we invoke
copyObject() on raw parse trees before doing parse analysis on them. Since
the bison grammar is capable of building heavily nested parsetrees while
itself using only minimal stack depth, this means that copyObject() can be
the front-line function that hits stack overflow before anything else does.
Accordingly, it had better have a check_stack_depth() call. I did a bit of
performance testing and found that this slows down copyObject() by only a
few percent, so the hit ought to be negligible in the context of complete
processing of a query.
Per off-list report from Toshihide Katayama. Back-patch to all supported
branches.
There were corner cases in which the planner would attempt to inline such
a function, which would result in a failure at runtime due to loss of
information about exactly what the result record type is. Fix by disabling
inlining when the function's recorded result type is RECORD. There might
be some sub-cases where inlining could still be allowed, but this is a
simple and backpatchable fix, so leave refinements for another day.
Per bug #5777 from Nate Carson.
Back-patch to all supported branches. 8.1 happens to avoid a core-dump
here, but it still does the wrong thing.
Most of the functions that execute XPath queries leaked the data structures
created by libxml2. This memory would not be recovered until end of
session, so it mounts up pretty quickly in any serious use of the feature.
Per report from Pavel Stehule, though this isn't his patch.
Back-patch to all supported branches.
When using default autovacuum_vac_cost_limit, autovac_balance_cost relied
on VacuumCostLimit to contain the correct global value ... but after the
first time through in a particular worker process, it didn't, because we'd
trashed it in previous iterations. Depending on the state of other autovac
workers, this could result in a steady reduction of the effective
cost_limit setting as a particular worker processed more and more tables,
causing it to go slower and slower. Spotted by Simon Poole (bug #5759).
Fix by saving and restoring the GUC variables in the loop in do_autovacuum.
In passing, improve a few comments.
Back-patch to 8.3 ... the cost rebalancing code has been buggy since it was
put in.
temporary indexes are not WAL-logged. We used a constant LSN for temporary
indexes, on the assumption that we don't need to worry about concurrent page
splits in temporary indexes because they're only visible to the current
session. But that assumption is wrong, it's possible to insert rows and
split pages in the same session, while a scan is in progress. For example,
by opening a cursor and fetching some rows, and INSERTing new rows before
fetching some more.
Fix by generating fake increasing LSNs, used in place of real LSNs in
temporary GiST indexes.
We must stay in the function's SPI context until done calling the iterator
that returns the set result. Otherwise, any attempt to invoke SPI features
in the python code called by the iterator will malfunction. Diagnosis and
patch by Jan Urbanski, per bug report from Jean-Baptiste Quenot.
Back-patch to 8.2; there was no support for SRFs in previous versions of
plpython.
We must not return any "okay to proceed" result code without having checked
for too many children, else we might fail later on when trying to add the
new child to one of the per-child state arrays. It's not clear whether
this oversight explains Stefan Kaltenbrunner's recent report, but it could
certainly produce a similar symptom.
Back-patch to 8.4; the logic was not broken before that.
This is needed to support debug_print_parse, per report from Jon Nelson.
Cursory testing via the regression tests suggests we aren't missing
anything else.
Once we have found a non-null constant argument, there is no need to
examine additional arguments of the COALESCE. The previous coding got it
right only if the constant was in the first argument position; otherwise
it tried to simplify following arguments too, leading to unexpected
behavior like this:
regression=# select coalesce(f1, 42, 1/0) from int4_tbl;
ERROR: division by zero
It's a minor corner case, but a bug is a bug, so back-patch all the way.
location read from backup label file can be found: wasShutdown was set
incorrectly when a backup label file was found.
Jeff Davis, with a little tweaking by me.
This code was just plain wrong: what you got was not a line through the
given point but a line almost indistinguishable from the Y-axis, although
not truly vertical. The only caller that tries to use this function with
m == DBL_MAX is dist_ps_internal for the case where the lseg is horizontal;
it would end up producing the distance from the given point to the place
where the lseg's line crosses the Y-axis. That function is used by other
operators too, so there are several operators that could compute wrong
distances from a line segment to something else. Per bug #5745 from
jindiax.
Back-patch to all supported branches.
The general design of memory management in Postgres is that intermediate
results computed by an expression are not freed until the end of the tuple
cycle. For expression indexes, ANALYZE has to re-evaluate each expression
for each of its sample rows, and it wasn't bothering to free intermediate
results until the end of processing of that index. This could lead to very
substantial leakage if the intermediate results were large, as in a recent
example from Jakub Ouhrabka. Fix by doing ResetExprContext for each sample
row. This necessitates adding a datumCopy step to ensure that the final
expression value isn't recycled too. Some quick testing suggests that this
change adds at worst about 10% to the time needed to analyze a table with
an expression index; which is annoying, but seems a tolerable price to pay
to avoid unexpected out-of-memory problems.
Back-patch to all supported branches.
length stored in the line pointer the same way it's calculated in the normal
heap_insert() codepath. As noted by Jeff Davis, the length stored by
raw_heap_insert() included padding but the one stored by the normal codepath
did not. While the mismatch seems to be harmless, inconsistency isn't good,
and the normal codepath has received a lot more testing over the years.
Backpatch to 8.3 where the heap rewrite code was introduced.
The original coding in FileClose() reset the file-is-temp flag before
unlinking the file, so that if control came back through due to an error,
it wouldn't try to unlink the file twice. This was correct when written,
but when the log_temp_files feature was added, the logging action was put
in between those two steps. An error occurring during the logging action
--- such as a query cancel --- would result in the unlink not getting done
at all, as in recent report from Michael Glaesemann.
To fix this, make sure that we do both the stat and the unlink before doing
anything that could conceivably CHECK_FOR_INTERRUPTS. There is a judgment
call here, which is which log message to emit first: if you can see only
one, which should it be? I chose to log unlink failure at the risk of
losing the log_temp_files log message --- after all, if the unlink does
fail, the temp file is still there for you to see.
Back-patch to all versions that have log_temp_files. The code was OK
before that.
Per recent investigation, the register stack can grow faster than the
regular stack depending on compiler and choice of options. To avoid
crashes we must check both stacks in check_stack_depth().
Back-patch to all supported versions.
Some buildfarm members fail the test with the original depth of 10 levels,
apparently because they are running at the minimum max_stack_depth setting
of 100kB and using ~ 10k per recursion level. While it might be
interesting to try to figure out why they're eating so much stack, it isn't
likely that any fix for that would be back-patchable. So just change the
test to recurse only 5 levels. The extra levels don't prove anything
correctness-wise anyway.
Tom Lane