being used in a PL/pgSQL FOR loop is closed was inadequate, as Tom Lane
pointed out. The bug affects FOR statement variants too, because you can
close an implicitly created cursor too by guessing the "<unnamed portal X>"
name created for it.
To fix that, "pin" the portal to prevent it from being dropped while it's
being used in a PL/pgSQL FOR loop. Backpatch all the way to 7.4 which is
the oldest supported version.
formats for geometric types. Per bug #5536 from Jon Strait, and my own
testing.
Back-patch to all supported branches, since this doco has been wrong right
along -- we certainly haven't changed the I/O behavior of these types in
many years.
but we have nevertheless exposed them to users via pg_get_expr(). It would
be too much maintenance effort to rigorously check the input, so put a hack
in place instead to restrict pg_get_expr() so that the argument must come
from one of the system catalog columns known to contain valid expressions.
Per report from Rushabh Lathia. Backpatch to 7.4 which is the oldest
supported version at the moment.
columns correctly. In passing, get rid of some dead logic in the
underlying get_sql_insert() etc functions --- there is no caller that
will pass null value-arrays to them.
Per bug report from Robert Voinea.
dblink_build_sql_insert() and related functions. In particular, be sure to
reject references to dropped and out-of-range column numbers. The numbers
are still interpreted as physical column numbers, though, for backward
compatibility.
This patch replaces Joe's patch of 2010-02-03, which handled only some aspects
of the problem.
lock the target relation just once per SQL function call. The original coding
obtained and released lock several times per call. Aside from saving a
not-insignificant number of cycles, this eliminates possible race conditions
if someone tries to modify the relation's schema concurrently. Also
centralize locking and permission-checking logic.
Problem noted while investigating a trouble report from Robert Voinea --- his
problem is still to be fixed, though.
This saves cycles in get_ps_display() on many popular platforms, and more
importantly ensures that get_ps_display() will correctly return an empty
string if init_ps_display() hasn't been called yet. Per trouble report
from Ray Stell, in which log_line_prefix %i produced junk early in backend
startup.
Back-patch to 8.0. 7.4 doesn't have %i and its version of get_ps_display()
makes no pretense of avoiding pad junk anyhow.
that is a regular table or view owned by a superuser. This prevents a
trojan horse attack whereby any unprivileged SQL user could create such a
table and insert code into it that would then get executed in other users'
sessions whenever they call pltcl functions.
Worse yet, because the code was automatically loaded into both the "normal"
and "safe" interpreters at first use, the attacker could execute unrestricted
Tcl code in the "normal" interpreter without there being any pltclu functions
anywhere, or indeed anyone else using pltcl at all: installing pltcl is
sufficient to open the hole. Change the initialization logic so that the
"unknown" code is only loaded into an interpreter when the interpreter is
first really used. (That doesn't add any additional security in this
particular context, but it seems a prudent change, and anyway the former
behavior violated the principle of least astonishment.)
Security: CVE-2010-1170
fundamentally insecure. Instead apply an opmask to the whole interpreter that
imposes restrictions on unsafe operations. These restrictions are much harder
to subvert than is Safe.pm, since there is no container to be broken out of.
Backported to release 7.4.
In releases 7.4, 8.0 and 8.1 this also includes the necessary backporting of
the two interpreters model for plperl and plperlu adopted in release 8.2.
In versions 8.0 and up, the use of Perl's POSIX module to undo its locale
mangling on Windows has become insecure with these changes, so it is
replaced by our own routine, which is also faster.
Nice side effects of the changes include that it is now possible to use perl's
"strict" pragma in a natural way in plperl, and that perl's $a and
$b variables now work as expected in sort routines, and that function
compilation is significantly faster.
Tim Bunce and Andrew Dunstan, with reviews from Alex Hunsaker and
Alexey Klyukin.
Security: CVE-2010-1169
Depending on which spec you read, field widths and precisions in %s may be
counted either in bytes or characters. Our code was assuming bytes, which
is wrong at least for glibc's implementation, and in any case libc might
have a different idea of the prevailing encoding than we do. Hence, for
portable results we must avoid using anything more complex than just "%s"
unless the string to be printed is known to be all-ASCII.
This patch fixes the cases I could find, including the psql formatting
failure reported by Hernan Gonzalez. In HEAD only, I also added comments
to some places where it appears safe to continue using "%.*s".
refers to itself (directly or indirectly). Instead, print a message when
recursion is detected, and don't expand the repeated reference. Per bug
#5448 from Francis Markham.
Back-patch to 8.0. Although the issue exists in 7.4 as well, it seems
impractical to fix there because of the lack of any state stack that
could be used to track active expansions.
The argument list for array_set() changed in 8.2 (in connection with allowing
nulls in arrays) but the newer argument list was used in the patches applied
to 8.1 and 8.0 branches. The patch for 7.4 was OK though. Per compiler
warnings.
returns EINVAL for an existing shared memory segment. Although it's not
terribly sensible, that behavior does meet the POSIX spec because EINVAL
is the appropriate error code when the existing segment is smaller than the
requested size, and the spec explicitly disclaims any particular ordering of
error checks. Moreover, it does in fact happen on OS X and probably other
BSD-derived kernels. (We were able to talk NetBSD into changing their code,
but purging that behavior from the wild completely seems unlikely to happen.)
We need to distinguish collision with a pre-existing segment from invalid size
request in order to behave sensibly, so it's worth some extra code here to get
it right. Per report from Gavin Kistner and subsequent investigation.
Back-patch to all supported versions, since any of them could get used
with a kernel having the debatable behavior.
memory if the result had zero rows, and also if there was any sort of error
while converting the result tuples into Python data. Reported and partially
fixed by Andres Freund.
Back-patch to all supported versions. Note: I haven't tested the 7.4 fix.
7.4's configure check for python is so obsolete it doesn't work on my
current machines :-(. The logic change is pretty straightforward though.
by a superuser -- "ALTER USER f RESET setting" already disallows removing such a
setting.
Apply the same treatment to ALTER DATABASE d RESET ALL when run by a database
owner that's not superuser.
so that we won't try to attach any context printouts to messages that get
emitted while exiting. Per report from Dennis Koegel, the context functions
won't necessarily work after we've started shutting down the backend, and it
seems possible that debug_query_string could be pointing at freed storage
as well. The context information doesn't seem particularly relevant to
such messages anyway, so there's little lost by suppressing it.
Back-patch to all supported branches. I can only demonstrate a crash with
log_disconnections messages back to 8.1, but the risk seems real in 8.0 and
before anyway.
The latter is considered unwarranted chumminess with the implementation,
and can lead to crashes with recent Perl versions.
Report and fix by Tim Bunce. Back-patch to all versions containing the
questionable coding pattern.
unless (1) the @ isn't quoted and (2) the filename isn't empty. This guards
against unexpectedly treating usernames or other strings in "flat files"
as inclusion requests, as seen in a recent trouble report from Ed L.
The empty-filename case would be guaranteed to misbehave anyway, because our
subsequent path-munging behavior results in trying to read the directory
containing the current input file.
I think this might finally explain the report at
http://archives.postgresql.org/pgsql-bugs/2004-05/msg00132.php
of a crash after printing "authentication file token too long, skipping",
since I was able to duplicate that message (though not a crash) on a
platform where stdio doesn't refuse to read directories. We never got
far in investigating that problem, but now I'm suspicious that the trigger
condition was an @ in the flat password file.
Back-patch to all active branches since the problem can be demonstrated in all
branches except HEAD. The test case, creating a user named "@", doesn't cause
a problem in HEAD since we got rid of the flat password file. Nonetheless it
seems like a good idea to not consider quoted @ as a file inclusion spec,
so I changed HEAD too.
set ferror() but never set feof(). This is known to be the case for recent
glibc when trying to read a directory as a file, and might be true for other
platforms/cases too. Per report from Ed L. (There is more that we ought to
do about his report, but this is one easily identifiable issue.)
in versions >= 8.3). The core code is more robust and efficient than what
was there before, and this also reduces risks involved in swapping different
libxml error handler settings.
Before 8.3, there is still some risk of problems if add-on modules such as
Perl invoke libxml without setting their own error handler. Given the lack
of reports I'm not sure there's a risk in practice, so I didn't take the
step of actually duplicating the core code into older contrib/xml2 branches.
Instead I just tweaked the existing code to ensure it didn't leave a dangling
pointer to short-lived memory when throwing an error.
This involves modifying the module to have a stable ABI, that is, the
xslt_process() function still exists even without libxslt. It throws a
runtime error if called, but doesn't prevent executing the CREATE FUNCTION
call. This is a good thing anyway to simplify cross-version upgrades.
These are unnecessary and probably dangerous. I don't see any immediate
risk situations in the core XML support or contrib/xml2 itself, but there
could be issues with external uses of libxml2, and in any case it's an
accident waiting to happen.
Prior to 8.3, these changes are not critical for compatibility with core
Postgres, since core had no libxml2 calls then. However there is still
a risk if contrib/xml2 is used along with libxml2 functionality in Perl
or other loadable modules. So back-patch to all versions.
Also back-patch addition of regression tests. I'm not sure how many of
the cases are interesting without the interaction with core xml code,
but a silly regression test is still better than none at all.
segment of XLOG_BACKUP_END record even if the the record is placed
at a segment boundary. Furthermore the previous implementation could
return nonexistent segment file name when the boundary is in segments
that has "FE" suffix; We never use segments with "FF" suffix.
Backpatch to 8.0, where hot backup was introduced.
Reported by Fujii Masao.
old memory context in plpython. Before only one of them was marked
volatile, but per report from Zdenek Kotala, some compilers do the
wrong thing here.
that happens to be composite itself. Per bug #5314 from Oleg Serov.
Backpatch to 8.0 --- 7.4 has got too many other shortcomings in
composite-type support to make this worth worrying about in that branch.
exceed the total number of non-dropped source table fields for
dblink_build_sql_*(). Addresses bug report from Rushabh Lathia.
Backpatch all the way to the 7.3 branch.
matching before recursing instead of after. The DFA match eliminates
unworkable midpoint choices a lot faster than the recursive check, in most
cases, so doing it first can speed things up; particularly in pathological
cases such as recently exhibited by Michael Glaesemann.
In addition, apply some cosmetic changes that were applied upstream (in the
Tcl project) at the same time, in order to sync with upstream version 1.15
of regexec.c.
Upstream apparently intends to backpatch this, so I will too. The
pathological behavior could be unpleasant if encountered in the field,
which seems to justify any risk of introducing new bugs.
Tom Lane, reviewed by Donal K. Fellows of Tcl project
Heikki Linnakangas