2cd7084524 / c6293249d change the way individual attributes in a
TupleDesc are stored / accessed. To reduce the effort of making
extensions compatible with postgresql 11, and to ease future
backpatching, backpatch introduction of TupleDescAttr() to all
releases. Do not backpatch change in storage, as that'd be a breaking
change for existing and working extensions.
Author: Andres Freund
Discussion: https://postgr.es/m/20170820181723.tdswdinzptbcwhrr@alap3.anarazel.de
Backpatch: 9.2-
Commit 3eb9a5e7c unintentionally introduced an ordering dependency
into restore_toc_entries_prefork(). The existing coding of
reduce_dependencies() contains a check to skip moving a TOC entry
to the ready_list if it wasn't initially in the pending_list.
This used to suffice to prevent reduce_dependencies() from trying to
move anything into the ready_list during restore_toc_entries_prefork(),
because the pending_list stayed empty throughout that phase; but it no
longer does. The problem doesn't manifest unless the TOC has been
reordered by SortTocFromFile, which is how I missed it in testing.
To fix, just add a test for ready_list == NULL, converting the call
with NULL from a poor man's sanity check into an explicit command
not to touch TOC items' list membership. Clarify some of the comments
around this; in particular, note the primary purpose of the check for
pending_list membership, which is to ensure that we can't try to restore
the same item twice, in case a TOC list forces it to be restored before
its dependency count goes to zero.
Per report from Fabrízio de Royes Mello. Back-patch to 9.3, like the
previous commit.
Discussion: https://postgr.es/m/CAFcNs+pjuv0JL_x4+=71TPUPjdLHOXA4YfT32myj_OrrZb4ohA@mail.gmail.com
It now emerges that we can only rely on Perl to tell us we must use
-D_USE_32BIT_TIME_T if it's Perl 5.13.4 or later. For older versions,
revert to our previous practice of assuming we need that symbol in
all 32-bit Windows builds. This is not ideal, but inquiring into
which compiler version Perl was built with seems far too fragile.
In any case, we had not previously had complaints about these old
Perl versions, so let's assume this is Good Enough. (It's still
better than the situation ante commit 5a5c2feca, in that at least
the effects are confined to PL/Perl rather than the whole PG build.)
Back-patch to all supported versions, like 5a5c2feca and predecessors.
Discussion: https://postgr.es/m/CANFyU97OVQ3+Mzfmt3MhuUm5NwPU=-FtbNH5Eb7nZL9ua8=rcA@mail.gmail.com
Although not confirmed and probably rare, if the newly allocated memory
is not already zero, this could possibly have caused some problems.
Also reorder the initializations slightly so they match the order of the
struct definition.
Author: Wong, Yi Wen <yiwong@amazon.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
This appears to have been an omission in the original commit
0d692a0dc9. All related information_schema views already include
foreign tables.
Reported-by: Nicolas Thauvin <nicolas.thauvin@dalibo.com>
Stress testing by Andreas Seltenreich disclosed longstanding problems that
occur if a FATAL exit (e.g. due to receipt of SIGTERM) occurs while we are
trying to execute a ROLLBACK of an already-failed transaction. In such a
case, xact.c is in TBLOCK_ABORT state, so that AbortOutOfAnyTransaction
would skip AbortTransaction and go straight to CleanupTransaction. This
led to an assert failure in an assert-enabled build (due to the ROLLBACK's
portal still having a cleanup hook) or without assertions, to a FATAL exit
complaining about "cannot drop active portal". The latter's not
disastrous, perhaps, but it's messy enough to want to improve it.
We don't really want to run all of AbortTransaction in this code path.
The minimum required to clean up the open portal safely is to do
AtAbort_Memory and AtAbort_Portals. It seems like a good idea to
do AtAbort_Memory unconditionally, to be entirely sure that we are
starting with a safe CurrentMemoryContext. That means that if the
main loop in AbortOutOfAnyTransaction does nothing, we need an extra
step at the bottom to restore CurrentMemoryContext = TopMemoryContext,
which I chose to do by invoking AtCleanup_Memory. This'll result in
calling AtCleanup_Memory twice in many of the paths through this function,
but that seems harmless and reasonably inexpensive.
The original motivation for the assertion in AtCleanup_Portals was that
we wanted to be sure that any user-defined code executed as a consequence
of the cleanup hook runs during AbortTransaction not CleanupTransaction.
That still seems like a valid concern, and now that we've seen one case
of the assertion firing --- which means that exactly that would have
happened in a production build --- let's replace the Assert with a runtime
check. If we see the cleanup hook still set, we'll emit a WARNING and
just drop the hook unexecuted.
This has been like this a long time, so back-patch to all supported
branches.
Discussion: https://postgr.es/m/877ey7bmun.fsf@ansel.ydns.eu
Commit 3c163a7fc's original choice to ignore all #define symbols whose
names begin with underscore turns out to be too simplistic. On Windows,
some Perl installations are built with -D_USE_32BIT_TIME_T, and we must
absorb that or we get the wrong result for sizeof(PerlInterpreter).
This effectively re-reverts commit ef58b87df, which injected that symbol
in a hacky way, making it apply to all of Postgres not just PL/Perl.
More significantly, it did so on *all* 32-bit Windows builds, even when
the Perl build to be used did not select this option; so that it fails
to work properly with some newer Perl builds.
By making this change, we would be introducing an ABI break in 32-bit
Windows builds; but fortunately we have not used type time_t in any
exported Postgres APIs in a long time. So it should be OK, both for
PL/Perl itself and for third-party extensions, if an extension library
is built with a different _USE_32BIT_TIME_T setting than the core code.
Patch by me, based on research by Ashutosh Sharma and Robert Haas.
Back-patch to all supported branches, as commit 3c163a7fc was.
Discussion: https://postgr.es/m/CANFyU97OVQ3+Mzfmt3MhuUm5NwPU=-FtbNH5Eb7nZL9ua8=rcA@mail.gmail.com
The sole useful effect of this function, to check that no catcache
entries have positive refcounts at transaction end, has really been
obsolete since we introduced ResourceOwners in PG 8.1. We reduced the
checks to assertions years ago, so that the function was a complete
no-op in production builds. There have been previous discussions about
removing it entirely, but consensus up to now was that it had some small
value as a cross-check for bugs in the ResourceOwner logic.
However, it now emerges that it's possible to trigger these assertions
if you hit an assert-enabled backend with SIGTERM during a call to
SearchCatCacheList, because that function temporarily increases the
refcounts of entries it's intending to add to a catcache list construct.
In a normal ERROR scenario, the extra refcounts are cleaned up by
SearchCatCacheList's PG_CATCH block; but in a FATAL exit we do a
transaction abort and exit without ever executing PG_CATCH handlers.
There's a case to be made that this is a generic hazard and we should
consider restructuring elog(FATAL) handling so that pending PG_CATCH
handlers do get run. That's pretty scary though: it could easily create
more problems than it solves. Preliminary stress testing by Andreas
Seltenreich suggests that there are not many live problems of this ilk,
so we rejected that idea.
There are more-localized ways to fix the problem; the most principled
one would be to use PG_ENSURE_ERROR_CLEANUP instead of plain PG_TRY.
But adding cycles to SearchCatCacheList isn't very appealing. We could
also weaken the assertions in AtEOXact_CatCache in some more or less
ad-hoc way, but that just makes its raison d'etre even less compelling.
In the end, the most reasonable solution seems to be to just remove
AtEOXact_CatCache altogether, on the grounds that it's not worth trying
to fix it. It hasn't found any bugs for us in many years.
Per report from Jeevan Chalke. Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAM2+6=VEE30YtRQCZX7_sCFsEpoUkFBV1gZazL70fqLn8rcvBA@mail.gmail.com
Since PostgreSQL 9.6, rolreplication no longer determines whether a role
can run pg_start_backup() and pg_stop_backup(), so remove that.
Add that this attribute determines whether a role can create and drop
replication slots.
Reported-by: Fujii Masao <masao.fujii@gmail.com>
find_composite_type_dependencies correctly found columns that are of
the specified type, and columns that are of arrays of that type, but
not columns that are domains or ranges over the given type, its array
type, etc. The most general way to handle this seems to be to assume
that any type that is directly dependent on the specified type can be
treated as a container type, and processed recursively (allowing us
to handle nested cases such as ranges over domains over arrays ...).
Since a type's array type already has such a dependency, we can drop
the existing special case for the array type.
The very similar logic in get_rels_with_domain was likewise a few
bricks shy of a load, as it supposed that a directly dependent type
could *only* be a sub-domain. This is already wrong for ranges over
domains, and it'll someday be wrong for arrays over domains.
Add test cases illustrating the problems, and back-patch to all
supported branches.
Discussion: https://postgr.es/m/15268.1502309024@sss.pgh.pa.us
FreeBSD's make, for one, sets the MAKELEVEL environment variable when
invoking commands. In the special Makefile we provide to hand off control
from a non-GNU make to GNU make, this causes GNU make to think it is a
child make invocation rather than top-level. That interferes with the hack
added in commit dcae5facc to cause the temp-install tree to be made only by
the top-level invocation of gmake. Unset the variable to prevent that.
Likewise unset MAKEFLAGS, which FreeBSD's make also sets, and which could
easily confuse gmake. There are no reports of actual trouble from that,
but it seems better to be proactive.
Back-patch to 9.5 where dcae5facc came in.
Thomas Munro, hacked a bit more by me
Discussion: https://postgr.es/m/CAEepm=1ueww35AXTkt1A3gyzZUqv5XCzh8RUNvJZAQAW=eOhVw@mail.gmail.com
Commit 1efc7e538 did a poor job of emulating existing logic for touching
Datums that might be expanded-object pointers. It didn't check for typlen
being -1 first, which meant it could crash on fixed-length pass-by-ref
values, and probably on cstring values as well. It also didn't use
DatumGetPointer before VARATT_IS_EXTERNAL_EXPANDED, which while currently
harmless is not according to documentation nor prevailing style.
I also think the lack of any explanation as to why datumSerialize makes
these particular nonobvious choices is pretty awful, so fix that.
Per report from Jarred Ward. Back-patch to 9.6 where this code came in.
Discussion: https://postgr.es/m/6F61E6D2-2F5E-4794-9479-A429BE1CEA4B@simple.com
lo_put() surely should require UPDATE permission, the same as lowrite(),
but it failed to check for that, as reported by Chapman Flack. Oversight
in commit c50b7c09d; backpatch to 9.4 where that was introduced.
Tom Lane and Michael Paquier
Security: CVE-2017-7548
Commit 3eefc51053 claimed to make
pg_user_mappings enforce the qualifications user_mapping_options had
been enforcing, but its removal of a longstanding restriction left them
distinct when the current user is the subject of a mapping yet has no
server privileges. user_mapping_options emits no rows for such a
mapping, but pg_user_mappings includes full umoptions. Change
pg_user_mappings to show null for umoptions. Back-patch to 9.2, like
the above commit.
Reviewed by Tom Lane. Reported by Jeff Janes.
Security: CVE-2017-7547
Some authentication methods allowed it, others did not. In the client-side,
libpq does not even try to authenticate with an empty password, which makes
using empty passwords hazardous: an administrator might think that an
account with an empty password cannot be used to log in, because psql
doesn't allow it, and not realize that a different client would in fact
allow it. To clear that confusion and to be be consistent, disallow empty
passwords in all authentication methods.
All the authentication methods that used plaintext authentication over the
wire, except for BSD authentication, already checked that the password
received from the user was not empty. To avoid forgetting it in the future
again, move the check to the recv_password_packet function. That only
forbids using an empty password with plaintext authentication, however.
MD5 and SCRAM need a different fix:
* In stable branches, check that the MD5 hash stored for the user does not
not correspond to an empty string. This adds some overhead to MD5
authentication, because the server needs to compute an extra MD5 hash, but
it is not noticeable in practice.
* In HEAD, modify CREATE and ALTER ROLE to clear the password if an empty
string, or a password hash that corresponds to an empty string, is
specified. The user-visible behavior is the same as in the stable branches,
the user cannot log in, but it seems better to stop the empty password from
entering the system in the first place. Secondly, it is fairly expensive to
check that a SCRAM hash doesn't correspond to an empty string, because
computing a SCRAM hash is much more expensive than an MD5 hash by design,
so better avoid doing that on every authentication.
We could clear the password on CREATE/ALTER ROLE also in stable branches,
but we would still need to check at authentication time, because even if we
prevent empty passwords from being stored in pg_authid, there might be
existing ones there already.
Reported by Jeroen van der Ham, Ben de Graaff and Jelte Fennema.
Security: CVE-2017-7546
The callers for GetOldestSafeDecodingTransactionId() all inverted the
argument for the argument introduced in 2bef06d516. Luckily this
appears to be inconsequential for the moment, as we wait for
concurrent in-progress transaction when assembling a
snapshot. Additionally this could only make a difference when adding a
second logical slot, because only a pre-existing slot could cause an
issue by lowering the returned xid dangerously much.
Reported-By: Antonin Houska
Discussion: https://postgr.es/m/32704.1496993134@localhost
Backport: 9.4-, where 2bef06d516 was backpatched to.
We don't actually support session tickets, since we do not create an SSL
session identifier. But it seems that OpenSSL will issue a session ticket
on-demand anyway, which will then fail when used. This results in
reconnection failures when using ticket-aware client-side SSL libraries
(such as the Npgsql .NET driver), as reported by Shay Rojansky.
To fix, just tell OpenSSL not to issue tickets. At some point in the
far future, we might consider enabling tickets instead. But the security
implications of that aren't entirely clear; and besides it would have
little benefit except for very short-lived database connections, which is
Something We're Bad At anyhow. It would take a lot of other work to get
to a point where that would really be an exciting thing to do.
While at it, also tell OpenSSL not to use a session cache. This doesn't
really do anything, since a backend would never populate the cache anyway,
but it might gain some micro-efficiencies and/or reduce security
exposures.
Patch by me, per discussion with Heikki Linnakangas and Shay Rojansky.
Back-patch to all supported versions.
Discussion: https://postgr.es/m/CADT4RqBU8N-csyZuzaook-c795dt22Zcwg1aHWB6tfVdAkodZA@mail.gmail.com
Because we push all ACL (i.e. GRANT/REVOKE) restore steps to the end,
materialized view refreshes were occurring while the permissions on
referenced objects were still at defaults. This led to failures if,
say, an MV owned by user A reads from a table owned by user B, even
if B had granted the necessary privileges to A. We've had multiple
complaints about that type of restore failure, most recently from
Jordan Gigov.
The ideal fix for this would be to start treating ACLs as dependency-
sortable objects, rather than hard-wiring anything about their dump order
(the existing approach is a messy kluge dating to commit dc0e76ca3).
But that's going to be a rather major change, and it certainly wouldn't
lead to a back-patchable fix. As a short-term solution, convert the
existing two-pass hack (ie, normal objects then ACLs) to a three-pass hack,
ie, normal objects then ACLs then matview refreshes. Because this happens
in RestoreArchive(), it will also fix the problem when restoring from an
existing archive-format dump.
(Note this means that if a matview refresh would have failed under the
permissions prevailing at dump time, it'll fail during restore as well.
We'll define that as user error rather than something we should try
to work around.)
To avoid performance loss in parallel restore, we need the matview
refreshes to still be parallelizable. Hence, clean things up enough
so that both ACLs and matviews are handled by the parallel restore
infrastructure, instead of reverting back to serial restore for ACLs.
There is still a final serial step, but it shouldn't normally have to
do anything; it's only there to try to recover if we get stuck due to
some problem like unresolved circular dependencies.
Patch by me, but it owes something to an earlier attempt by Kevin Grittner.
Back-patch to 9.3 where materialized views were introduced.
Discussion: https://postgr.es/m/28572.1500912583@sss.pgh.pa.us
Commit 4d57e83816 added support for getting I/O errors out of zlib,
but it introduced a portability problem for systems without zlib.
Repair by wrapping the zlib call inside #ifdef and restore the original
code in the other branch.
This serves to illustrate the inadequacy of the zlib abstraction in
pg_backup_archiver: there is no way to call gzerror() in that
abstraction. This means that the several places that call GZREAD and
GZWRITE are currently doing error reporting wrongly, but ENOTIME to get
it fixed before next week's release set.
Backpatch to 9.4, like the commit that introduced the problem.
Some error reports were reporting strerror(errno), which for some error
conditions coming from zlib are wrong, resulting in confusing reports
such as
pg_restore: [compress_io] could not read from input file: Success
which makes no sense. To correctly extract the error message we need to
use gzerror(), so let's do that.
This isn't as comprehensive or as neat as I would like, but at least it
should improve things in many common cases. The zlib abstraction in
compress_io does not seem to be applied consistently enough; we could
perhaps improve that, but it seems master-only material, not a bug fix
for back-patching.
This problem goes back all the way, but I decided to apply back to 9.4
only, because older branches don't contain commit 14ea89366 which this
change depends on.
Authors: Vladimir Kunschikov, Álvaro Herrera
Discussion: https://postgr.es/m/1498120508308.9826@infotecs.ru
FlightAware is still maintaining this, and indeed is seemingly being
more active with it than the pgtclng fork is. List both, for the
time being anyway.
In the back branches, also back-port commit e20f679f6 and other
recent updates to the client-interfaces list. I think these are
probably of current interest to users of back branches. I did
not touch the list of externally maintained PLs in the back
branches, though. Those are much more likely to be server version
sensitive, and I don't know which of these PLs work all the way back.
Discussion: https://postgr.es/m/20170730162612.1449.58796@wrigleys.postgresql.org
init_htab(), with #define HASH_DEBUG, prints a bunch of hashtable
parameters. It used to also print nentries, but commit 44ca4022f changed
that to "hash_get_num_entries(hctl)", which is wrong (the parameter should
be "hashp").
Rather than correct the coding, though, let's just remove that field from
the printout. The table must be empty, since we just finished building
it, so expensively calculating the number of entries is rather pointless.
Moreover hash_get_num_entries makes assumptions (about not needing locks)
which we could do without in debugging code.
Noted by Choi Doo-Won in bug #14764. Back-patch to 9.6 where the
faulty code was introduced.
Discussion: https://postgr.es/m/20170802032353.8424.12274@wrigleys.postgresql.org
XLByteToSeg and XLByteToPrevSeg calculate only a segment number. The
definition of these macros were modified by commit
dfda6ebaec but the comment remain
unchanged.
Patch by Yugo Nagata. Back patched to 9.3 and beyond.
Previously the docs just said "5.8 or later". Experimentation shows
that while you can build on Unix from a git checkout with 5.8.0,
compiling recent PL/Perl requires at least 5.8.1, and you won't be
able to run the TAP tests with less than 5.8.3 because that's when
they added "prove". (I do not have any information on just what the
MSVC build scripts require.)
Since all these versions are quite ancient, let's not split hairs
in the docs, but just say that 5.8.3 is the minimum requirement.
Discussion: https://postgr.es/m/16894.1501392088@sss.pgh.pa.us
The comment for dumpACL() got neglected when initacls and initracls were
added and the discussion of what 'racls' is wasn't very clear either.
Per complaint from Tom.
