Several places in NUM_numpart_from_char(), which is called from the SQL
function to_number(text, text), could accidentally read one byte past
the end of the input buffer (which comes from the input text datum and
is not null-terminated).
1. One leading space character would be skipped, but there was no check
that the input was at least one byte long. This does not happen in
practice, but for defensiveness, add a check anyway.
2. Commit 4a3a1e2cf apparently accidentally doubled that code that skips
one space character (so that two spaces might be skipped), but there
was no overflow check before skipping the second byte. Fix by
removing that duplicate code.
3. A logic error would allow a one-byte over-read when looking for a
trailing sign (S) placeholder.
In each case, the extra byte cannot be read out directly, but looking at
it might cause a crash.
The third item was discovered by Piotr Stefaniak, the first two were
found and analyzed by Tom Lane and Peter Eisentraut.
ExecEvalCase() tried to save a cycle or two by passing
&econtext->caseValue_isNull as the isNull argument to its sub-evaluation of
the CASE value expression. If that subexpression itself contained a CASE,
then *isNull was an alias for econtext->caseValue_isNull within the
recursive call of ExecEvalCase(), leading to confusion about whether the
inner call's caseValue was null or not. In the worst case this could lead
to a core dump due to dereferencing a null pointer. Fix by not assigning
to the global variable until control comes back from the subexpression.
Also, avoid using the passed-in isNull pointer transiently for evaluation
of WHEN expressions. (Either one of these changes would have been
sufficient to fix the known misbehavior, but it's clear now that each of
these choices was in itself dangerous coding practice and best avoided.
There do not seem to be any similar hazards elsewhere in execQual.c.)
Also, it was possible for inlining of a SQL function that implements the
equality operator used for a CASE comparison to result in one CASE
expression's CaseTestExpr node being inserted inside another CASE
expression. This would certainly result in wrong answers since the
improperly nested CaseTestExpr would be caused to return the inner CASE's
comparison value not the outer's. If the CASE values were of different
data types, a crash might result; moreover such situations could be abused
to allow disclosure of portions of server memory. To fix, teach
inline_function to check for "bare" CaseTestExpr nodes in the arguments of
a function to be inlined, and avoid inlining if there are any.
Heikki Linnakangas, Michael Paquier, Tom Lane
Report: https://github.com/greenplum-db/gpdb/pull/327
Report: <4DDCEEB8.50602@enterprisedb.com>
Security: CVE-2016-5423
Due to simplistic quoting and confusion of database names with conninfo
strings, roles with the CREATEDB or CREATEROLE option could escalate to
superuser privileges when a superuser next ran certain maintenance
commands. The new coding rule for PQconnectdbParams() calls, documented
at conninfo_array_parse(), is to pass expand_dbname=true and wrap
literal database names in a trivial connection string. Escape
zero-length values in appendConnStrVal(). Back-patch to 9.1 (all
supported versions).
Nathan Bossart, Michael Paquier, and Noah Misch. Reviewed by Peter
Eisentraut. Reported by Nathan Bossart.
Security: CVE-2016-5424
Rename these newly-extern functions with terms more typical of their new
neighbors. No functional changes; a subsequent commit will use them in
more places. Back-patch to 9.1 (all supported versions). Back branches
lack src/fe_utils, so instead rename the functions in place; the
subsequent commit will copy them into the other programs using them.
Security: CVE-2016-5424
Back-patch commit 2953cd6d17 and certain
runPgDump() bits of 3dee636e04 to 9.2 and
9.1. This synchronizes their doConnStrQuoting() implementations with
later releases. Subsequent security patches will modify that function.
Security: CVE-2016-5424
The incorrect quoting may have permitted arbitrary command execution.
At a minimum, it gave broader control over the command line to actors
supposed to have control over a single argument. Back-patch to 9.1 (all
supported versions).
Security: CVE-2016-5424
These characters prematurely terminate Windows shell command processing,
causing the shell to execute a prefix of the intended command. The
chief alternative to rejecting these characters was to bypass the
Windows shell with CreateProcess(), but the ability to use such names
has little value. Back-patch to 9.1 (all supported versions).
This change formally revokes support for these characters in database
names and roles names. Don't document this; the error message is
self-explanatory, and too few users would benefit. A future major
release may forbid creation of databases and roles so named. For now,
check only at known weak points in pg_dumpall. Future commits will,
without notice, reject affected names from other frontend programs.
Also extend the restriction to pg_dumpall --dbname=CONNSTR arguments and
--file arguments. Unlike the effects on role name arguments and
database names, this does not reflect a broad policy change. A
migration to CreateProcess() could lift these two restrictions.
Reviewed by Peter Eisentraut.
Security: CVE-2016-5424
These programs nominally accepted conninfo strings, but they would
proceed to use the original dbname parameter as though it were an
unadorned database name. This caused "reindexdb dbname=foo" to issue an
SQL command that always failed, and other programs printed a conninfo
string in error messages that purported to print a database name. Fix
both problems by using PQdb() to retrieve actual database names.
Continue to print the full conninfo string when reporting a connection
failure. It is informative there, and if the database name is the sole
problem, the server-side error message will include the name. Beyond
those user-visible fixes, this allows a subsequent commit to synthesize
and use conninfo strings without that implementation detail leaking into
messages. As a side effect, the "vacuuming database" message now
appears after, not before, the connection attempt. Back-patch to 9.1
(all supported versions).
Reviewed by Michael Paquier and Peter Eisentraut.
Security: CVE-2016-5424
The decision to reuse values of parameters from a previous connection
has been based on whether the new target is a conninfo string. Add this
means of overriding that default. This feature arose as one component
of a fix for security vulnerabilities in pg_dump, pg_dumpall, and
pg_upgrade, so back-patch to 9.1 (all supported versions). In 9.3 and
later, comment paragraphs that required update had already-incorrect
claims about behavior when no connection is open; fix those problems.
Security: CVE-2016-5424
In arguments, these meta-commands wrongly treated each pair as closing
the double quoted string. Make the behavior match the documentation.
This is a compatibility break, but I more expect to find software with
untested reliance on the documented behavior than software reliant on
today's behavior. Back-patch to 9.1 (all supported versions).
Reviewed by Tom Lane and Peter Eisentraut.
Security: CVE-2016-5424
If ANALYZE found no repeated non-null entries in its sample, it set the
column's stadistinct value to -1.0, intending to indicate that the entries
are all distinct. But what this value actually means is that the number
of distinct values is 100% of the table's rowcount, and thus it was
overestimating the number of distinct values by however many nulls there
are. This could lead to very poor selectivity estimates, as for example
in a recent report from Andreas Joseph Krogh. We should discount the
stadistinct value by whatever we've estimated the nulls fraction to be.
(That is what will happen if we choose to use a negative stadistinct for
a column that does have repeated entries, so this code path was just
inconsistent.)
In addition to fixing the stadistinct entries stored by several different
ANALYZE code paths, adjust the logic where get_variable_numdistinct()
forces an "all distinct" estimate on the basis of finding a relevant unique
index. Unique indexes don't reject nulls, so there's no reason to assume
that the null fraction doesn't apply.
Back-patch to all supported branches. Back-patching is a bit of a judgment
call, but this problem seems to affect only a few users (else we'd have
identified it long ago), and it's bad enough when it does happen that
destabilizing plan choices in a worse direction seems unlikely.
Patch by me, with documentation wording suggested by Dean Rasheed
Report: <VisenaEmail.26.df42f82acae38a58.156463942b8@tc7-visena>
Discussion: <16143.1470350371@sss.pgh.pa.us>
Beginning with the next development cycle, PG servers will report two-part
not three-part version numbers. Fix libpq so that it will compute the
correct numeric representation of such server versions for reporting by
PQserverVersion(). It's desirable to get this into the field and
back-patched ASAP, so that older clients are more likely to understand the
new server version numbering by the time any such servers are in the wild.
(The results with an old client would probably not be catastrophic anyway
for a released server; for example "10.1" would be interpreted as 100100
which would be wrong in detail but would not likely cause an old client to
misbehave badly. But "10devel" or "10beta1" would result in sversion==0
which at best would result in disabling all use of modern features.)
Extracted from a patch by Peter Eisentraut; comments added by me
Patch: <802ec140-635d-ad86-5fdf-d3af0e260c22@2ndquadrant.com>
DST law changes in Kemerovo and Novosibirsk. Historical corrections for
Azerbaijan, Belarus, and Morocco. Asia/Novokuznetsk and Asia/Novosibirsk
now use numeric time zone abbreviations instead of invented ones. Zones
for Antarctic bases and other locations that have been uninhabited for
portions of the time span known to the tzdata database now report "-00"
rather than "zzz" as the zone abbreviation for those time spans.
Also, I decided to remove some of the timezone/data/ files that we don't
use. At one time that subdirectory was a complete copy of what IANA
distributes in the tzdata tarballs, but that hasn't been true for a long
time. There seems no good reason to keep shipping those specific files
but not others; they're just bloating our tarballs.
The help message for pg_basebackup specifies that the numbers 0 through 9
are accepted as valid values of -Z option. But, previously -Z 0 was rejected
as an invalid compression level.
Per discussion, it's better to make pg_basebackup treat 0 as valid
compression level meaning no compression, like pg_dump.
Back-patch to all supported versions.
Reported-By: Jeff Janes
Reviewed-By: Amit Kapila
Discussion: CAMkU=1x+GwjSayc57v6w87ij6iRGFWt=hVfM0B64b1_bPVKRqg@mail.gmail.com
This text was added by commit ff213239c, and not long thereafter obsoleted
by commit 4adc2f72a (which made the test depend on NBuffers instead); but
nobody noticed the need for an update. Commit 9563d5b5e adds some further
dependency on maintenance_work_mem, but the existing verbiage seems to
cover that with about as much precision as we really want here. Let's
just take it all out rather than leaving ourselves open to more errors of
omission in future. (That solution makes this change back-patchable, too.)
Noted by Peter Geoghegan.
Discussion: <CAM3SWZRVANbj9GA9j40fAwheQCZQtSwqTN1GBTVwRrRbmSf7cg@mail.gmail.com>
Per the fgets() specification, it cannot return without reading some data
unless it reports EOF or error. So the code here assumed that the data
buffer would necessarily be nonempty when we go to check for a newline
having been read. However, Agostino Sarubbo noticed that this could fail
to be true if the first byte of the data is a NUL (\0). The fgets() API
doesn't really work for embedded NULs, which is something I don't feel
any great need for us to worry about since we generally don't allow NULs
in SQL strings anyway. But we should not access off the end of our own
buffer if the case occurs. Normally this would just be a harmless read,
but if you were unlucky the byte before the buffer would contain '\n'
and we'd overwrite it with '\0', and if you were really unlucky that
might be valuable data and psql would crash.
Agostino reported this to pgsql-security, but after discussion we concluded
that it isn't worth treating as a security bug; if you can control the
input to psql you can do far more interesting things than just maybe-crash
it. Nonetheless, it is a bug, so back-patch to all supported versions.
Commits 4452000f3 et al established semantics for NullTest.argisrow that
are a bit different from its initial conception: rather than being merely
a cache of whether we've determined the input to have composite type,
the flag now has the further meaning that we should apply field-by-field
testing as per the standard's definition of IS [NOT] NULL. If argisrow
is false and yet the input has composite type, the construct instead has
the semantics of IS [NOT] DISTINCT FROM NULL. Update the comments in
primnodes.h to clarify this, and fix ruleutils.c and deparse.c to print
such cases correctly. In the case of ruleutils.c, this merely results in
cosmetic changes in EXPLAIN output, since the case can't currently arise
in stored rules. However, it represents a live bug for deparse.c, which
would formerly have sent a remote query that had semantics different
from the local behavior. (From the user's standpoint, this means that
testing a remote nested-composite column for null-ness could have had
unexpected recursive behavior much like that fixed in 4452000f3.)
In a related but somewhat independent fix, make plancat.c set argisrow
to false in all NullTest expressions constructed to represent "attnotnull"
constructs. Since attnotnull is actually enforced as a simple null-value
check, this is a more accurate representation of the semantics; we were
previously overpromising what it meant for composite columns, which might
possibly lead to incorrect planner optimizations. (It seems that what the
SQL spec expects a NOT NULL constraint to mean is an IS NOT NULL test, so
arguably we are violating the spec and should fix attnotnull to do the
other thing. If we ever do, this part should get reverted.)
Back-patch, same as the previous commit.
Discussion: <10682.1469566308@sss.pgh.pa.us>
The docs failed to explain that LIKE INCLUDING INDEXES would not preserve
the names of indexes and associated constraints. Also, it wasn't mentioned
that EXCLUDE constraints would be copied by this option. The latter
oversight seems enough of a documentation bug to justify back-patching.
In passing, do some minor copy-editing in the same area, and add an entry
for LIKE under "Compatibility", since it's not exactly a faithful
implementation of the standard's feature.
Discussion: <20160728151154.AABE64016B@smtp.hushmail.com>
start_postmaster() registered stop_postmaster_atexit as an atexit(3)
callback each time through, although the obvious intention was to do
so only once per program run. The extra registrations were harmless,
so long as we didn't exceed ATEXIT_MAX, but still it's a bug.
Artur Zakirov, with bikeshedding by Kyotaro Horiguchi and me
Discussion: <d279e817-02b5-caa6-215f-cfb05dce109a@postgrespro.ru>
The SQL standard appears to specify that IS [NOT] NULL's tests of field
nullness are non-recursive, ie, we shouldn't consider that a composite
field with value ROW(NULL,NULL) is null for this purpose.
ExecEvalNullTest got this right, but eval_const_expressions did not,
leading to weird inconsistencies depending on whether the expression
was such that the planner could apply constant folding.
Also, adjust the docs to mention that IS [NOT] DISTINCT FROM NULL can be
used as a substitute test if a simple null check is wanted for a rowtype
argument. That motivated reordering things so that IS [NOT] DISTINCT FROM
is described before IS [NOT] NULL. In HEAD, I went a bit further and added
a table showing all the comparison-related predicates.
Per bug #14235. Back-patch to all supported branches, since it's certainly
undesirable that constant-folding should change the semantics.
Report and patch by Andrew Gierth; assorted wordsmithing and revised
regression test cases by me.
Report: <20160708024746.1410.57282@wrigleys.postgresql.org>
In btree_gin and citext, avoid some not-particularly-interesting
dependencies on the sorting of 'aa'. In tsearch2, use COLLATE "C" to
remove an uninteresting dependency on locale sort order (and thereby
allow removal of a variant expected-file).
Also, in citext, avoid assuming that lower('I') = 'i'. This isn't relevant
to Danish but it does fail in Turkish.
Another peculiarity of Danish locale is that it has an unusual idea
of how to sort upper vs. lower case. One of the pltcl test cases has
an issue with that. Now that COLLATE works in all supported branches,
we can just change the test to be locale-independent, and get rid of
the variant expected file that used to support non-C locales.
Back-patch commit 1c1a7cbd6a, along with subsequent portability
fixes, into all active branches. Also, back-patch commits 696027727 and
596857043 (addition of zic -P option) into 9.1 and 9.2, just to reduce
differences between the branches. src/timezone/ is now largely identical
in all active branches, except that in 9.1, pgtz.c retains the
initial-timezone-selection code that was moved over to initdb in 9.2.
Ordinarily we wouldn't risk this much code churn in back branches, but it
seems necessary in this case, because among the changes are two feature
additions in the "zic" zone data file compiler (a larger limit on the
number of allowed DST transitions, and addition of a "%z" escape in zone
abbreviations). IANA have not yet started to use those features in their
tzdata files, but presumably they will before too long. If we don't update
then we'll be unable to adopt new timezone data. Also, installations built
with --with-system-tzdata (which includes most distro-supplied builds, I
believe) might fail even if we don't update our copies of the data files.
There are assorted bug fixes too, mostly affecting obscure timezones or
post-2037 dates.
Discussion: <13601.1468868947@sss.pgh.pa.us>
The old code used SEQ_MINVALUE to get the smallest int64 value. This
was done as a convenience to avoid having to deal with INT64_IS_BUSTED,
but that is obsolete now. Also, it is incorrect because the smallest
int64 value is actually SEQ_MINVALUE-1. Fix by writing out the constant
the long way, as it is done elsewhere in the code.
The Assert() here seems unreasonably optimistic. Andreas Seltenreich
found that it could fail with NaNs in the input geometries, and it
seems likely to me that it might fail in corner cases due to roundoff
error, even for ordinary input values. As a band-aid, make the function
return SQL NULL instead of crashing.
Report: <87d1md1xji.fsf@credativ.de>
When heap_update needs to look for a page for the new tuple version,
because the current one doesn't have sufficient free space, or when
columns have to be processed by the tuple toaster, it has to release the
lock on the old page during that. Otherwise there'd be lock ordering and
lock nesting issues.
To avoid concurrent sessions from trying to update / delete / lock the
tuple while the page's content lock is released, the tuple's xmax is set
to the current session's xid.
That unfortunately was done without any WAL logging, thereby violating
the rule that no XIDs may appear on disk, without an according WAL
record. If the database were to crash / fail over when the page level
lock is released, and some activity lead to the page being written out
to disk, the xid could end up being reused; potentially leading to the
row becoming invisible.
There might be additional risks by not having t_ctid point at the tuple
itself, without having set the appropriate lock infomask fields.
To fix, compute the appropriate xmax/infomask combination for locking
the tuple, and perform WAL logging using the existing XLOG_HEAP_LOCK
record. That allows the fix to be backpatched.
This issue has existed for a long time. There appears to have been
partial attempts at preventing dangers, but these never have fully been
implemented, and were removed a long time ago, in
11919160 (cf. HEAP_XMAX_UNLOGGED).
In master / 9.6, there's an additional issue, namely that the
visibilitymap's freeze bit isn't reset at that point yet. Since that's a
new issue, introduced only in a892234f83, that'll be fixed in a
separate commit.
Author: Masahiko Sawada and Andres Freund
Reported-By: Different aspects by Thomas Munro, Noah Misch, and others
Discussion: CAEepm=3fWAbWryVW9swHyLTY4sXVf0xbLvXqOwUoDiNCx9mBjQ@mail.gmail.com
Backpatch: 9.1/all supported versions
Document that index storage is dependent on the operating system's
collation library ordering, and any change in that ordering can create
invalid indexes.
Discussion: 20160617154311.GB19359@momjian.us
Backpatch-through: 9.1
If there's anyplace in our SGML docs that explains this behavior, I can't
find it right at the moment. Add an explanation in "Dependency Tracking"
which seems like the authoritative place for such a discussion. Per
gripe from Michelle Schwan.
While at it, update this section's example of a dependency-related
error message: they last looked like that in 8.3. And remove the
explanation of dependency updates from pre-7.3 installations, which
is probably no longer worth anybody's brain cells to read.
The bogus error message example seems like an actual documentation bug,
so back-patch to all supported branches.
Discussion: <20160620160047.5792.49827@wrigleys.postgresql.org>
In the 9.1 branch only, modify test_postmaster_connection() so that it
will wait up to 10 seconds, not 5, for the postmaster pid file to appear.
This is a much simpler and safer, if less complete, way of addressing
the buildfarm instability issues we hoped to solve with c869a7d5b.
Discussion: <20160618042812.5798.85609@wrigleys.postgresql.org>
This reverts commit c869a7d5b4.
As pointed out by Maksym Sobolyev in bug #14199, that approach doesn't
work if the postmaster forks itself an extra time due to silent_mode
being enabled. We removed silent_mode in 9.2, so the pg_ctl change is
fine in 9.2 and later, but it fails when that option is enabled in 9.1.
Seeing that 9.1 is close to end-of-life, let's adopt the most conservative
fix we can, which is to revert the pg_ctl change in the 9.1 branch.
Discussion: <20160618042812.5798.85609@wrigleys.postgresql.org>
Dilian Palauzov pointed out in bug #14201 that the docs failed to mention
the possibility of %R producing '(' due to an unmatched parenthesis.
He proposed just adding that in the same style as the other options were
listed; but it seemed to me that the sentence was already nearly
unintelligible, so I rewrote it a bit more extensively.
Report: <20160619121113.5789.68274@wrigleys.postgresql.org>
The inet/cidr types sometimes failed to reject IPv6 inputs with too many
colon-separated fields, instead translating them to '::/0'. This is the
result of a thinko in the original ISC code that seems to be as yet
unreported elsewhere. Per bug #14198 from Stefan Kaltenbrunner.
Report: <20160616182222.5798.959@wrigleys.postgresql.org>
pg_type_aclmask reported the wrong type's OID when complaining that
it could not find a type's typelem. It also failed to provide a
suitable errcode when the initially given OID doesn't exist (which
is a user-facing error, since that OID can be user-specified).
pg_foreign_data_wrapper_aclmask and pg_foreign_server_aclmask likewise
lacked errcode specifications. Trivial cosmetic adjustments too.
The wrong-type-OID problem was reported by Petru-Florin Mihancea in
bug #14186; the other issues noted by me while reading the code.
These errors all seem to be aboriginal in the respective routines, so
back-patch as necessary.
Report: <20160613163159.5798.52928@wrigleys.postgresql.org>
Document these as "nearest integer >= argument" and "nearest integer <=
argument", which will hopefully be less confusing than the old formulation.
New wording is from Matlab via Dean Rasheed.
I changed the pg_description entries as well as the SGML docs. In the
back branches, this will only affect installations initdb'd in the future,
but it should be harmless otherwise.
Discussion: <CAEZATCW3yzJo-NMSiQs5jXNFbTsCEftZS-Og8=FvFdiU+kYuSA@mail.gmail.com>
In VPATH builds, the build directory was not being searched for files in
GETTEXT_FILES, leading to failure to construct the .pot files. This has
bit me all along, but never hard enough to get it fixed; I suppose not a
lot of people uses VPATH and NLS-enabled builds, and those that do,
don't do "make update-po" often.
This is a longstanding problem, so backpatch all the way back.
