This is a possibly-vain effort to silence a Coverity warning about
bogus endianness dependency. The code's fine, because it takes care
of endianness issues for itself, but Coverity sees an int64 being
passed to an int* argument and not unreasonably suspects something's
wrong. I'm not sure if putting the void* cast in the way will shut it
up; but it can't hurt and seems better from a documentation standpoint
anyway, since the pointer is not used as an int* in this code path.
Just for a bit of additional safety, verify that the result length
is 8 bytes as expected.
Back-patch to 9.3 where the code in question was added.
The SGML docs claimed that 1-byte integers could be sent or received with
the "isint" options, but no such behavior has ever been implemented in
pqGetInt() or pqPutInt(). The in-code documentation header for PQfn() was
even less in tune with reality, and the code itself used parameter names
matching neither the SGML docs nor its libpq-fe.h declaration. Do a bit
of additional wordsmithing on the SGML docs while at it.
Since the business about 1-byte integers is a clear documentation bug,
back-patch to all supported branches.
If libpq output buffer is full, pqSendSome() function tries to drain any
incoming data. This avoids deadlock, if the server e.g. sends a lot of
NOTICE messages, and blocks until we read them. However, pqSendSome() only
did that in blocking mode. In non-blocking mode, the deadlock could still
happen.
To fix, take a two-pronged approach:
1. Change the documentation to instruct that when PQflush() returns 1, you
should wait for both read- and write-ready, and call PQconsumeInput() if it
becomes read-ready. That fixes the deadlock, but applications are not going
to change overnight.
2. In pqSendSome(), drain the input buffer before returning 1. This
alleviates the problem for applications that only wait for write-ready. In
particular, a slow but steady stream of NOTICE messages during COPY FROM
STDIN will no longer cause a deadlock. The risk remains that the server
attempts to send a large burst of data and fills its output buffer, and at
the same time the client also sends enough data to fill its output buffer.
The application will deadlock if it goes to sleep, waiting for the socket
to become write-ready, before the server's data arrives. In practice,
NOTICE messages and such that the server might be sending are usually
short, so it's highly unlikely that the server would fill its output buffer
so quickly.
Backpatch to all supported versions.
After finding an "=" character, the pointer was advanced twice when it
should only advance once. This is harmless as long as the value after "="
has at least one character; but if it doesn't, we'd miss the terminator
character and include too much in the value.
In principle this could lead to reading off the end of memory. It does not
seem worth treating as a security issue though, because it would happen on
client side, and besides client logic that's taking conninfo strings from
untrusted sources has much worse security problems than this.
Report and patch received off-list from Thomas Fanghaenel.
Back-patch to 9.2 where the faulty code was introduced.
When ecpg was rewritten to the new protocol version not all variable types
were corrected. This patch rewrites the code for these types to fix that. It
also fixes the documentation to correctly tell the status of array handling.
strncpy() has a well-deserved reputation for being unsafe, so make an
effort to get rid of nearly all occurrences in HEAD.
A large fraction of the remaining uses were passing length less than or
equal to the known strlen() of the source, in which case no null-padding
can occur and the behavior is equivalent to memcpy(), though doubtless
slower and certainly harder to reason about. So just use memcpy() in
these cases.
In other cases, use either StrNCpy() or strlcpy() as appropriate (depending
on whether padding to the full length of the destination buffer seems
useful).
I left a few strncpy() calls alone in the src/timezone/ code, to keep it
in sync with upstream (the IANA tzcode distribution). There are also a
few such calls in ecpg that could possibly do with more analysis.
AFAICT, none of these changes are more than cosmetic, except for the four
occurrences in fe-secure-openssl.c, which are in fact buggy: an overlength
source leads to a non-null-terminated destination buffer and ensuing
misbehavior. These don't seem like security issues, first because no stack
clobber is possible and second because if your values of sslcert etc are
coming from untrusted sources then you've got problems way worse than this.
Still, it's undesirable to have unpredictable behavior for overlength
inputs, so back-patch those four changes to all active branches.
Coverity complained that the "else" added to fillPGconn() was unreachable,
which it was. Remove the dead code. In passing, rearrange the tests so as
not to bother trying to fetch values for options that can't be assigned.
Pre-9.3 did not have that issue, but it did have a "return" that should be
"goto oom_error" to ensure that a suitable error message gets filled in.
If the "dbname" attribute in PQconnectDBParams contained a connection string
or URI (and expand_dbname = TRUE), the database name from the connection
string could not be overridden by a subsequent "dbname" keyword in the
array. That was not intentional; all other options can be overridden.
Furthermore, any subsequent "dbname" caused the connection string from the
first dbname value to be processed again, overriding any values for the same
options that were given between the connection string and the second dbname
option.
In the passing, clarify in the docs that only the first dbname option in the
array is parsed as a connection string.
Alex Shulgin. Backpatch to all supported versions.
An out-of-memory in most of these would lead to strange behavior, like
connecting to a different database than intended, but some would lead to
an outright segfault.
Alex Shulgin and me. Backpatch to all supported versions.
If you call PQreset() repeatedly, and the connection cannot be
re-established, the error messages from the failed connection attempts
kept accumulating in the error string.
Fixes bug #11455 reported by Caleb Epstein. Backpatch to all supported
versions.
The EOF-detection logic in pqReadData was a bit confused about who should
set up the error message in case the kernel gives us read-ready-but-no-data
rather than ECONNRESET or some other explicit error condition. Since the
whole point of this situation is that the lower-level functions don't know
there's anything wrong, pqReadData itself must set up the message. But
keep the assumption that if an errno was reported, a message was set up at
lower levels.
Per bug #11712 from Marko Tiikkaja. It's been like this for a very long
time, so back-patch to all supported branches.
Up to now, PG has assumed that any given timezone abbreviation (such as
"EDT") represents a constant GMT offset in the usage of any particular
region; we had a way to configure what that offset was, but not for it
to be changeable over time. But, as with most things horological, this
view of the world is too simplistic: there are numerous regions that have
at one time or another switched to a different GMT offset but kept using
the same timezone abbreviation. Almost the entire Russian Federation did
that a few years ago, and later this month they're going to do it again.
And there are similar examples all over the world.
To cope with this, invent the notion of a "dynamic timezone abbreviation",
which is one that is referenced to a particular underlying timezone
(as defined in the IANA timezone database) and means whatever it currently
means in that zone. For zones that use or have used daylight-savings time,
the standard and DST abbreviations continue to have the property that you
can specify standard or DST time and get that time offset whether or not
DST was theoretically in effect at the time. However, the abbreviations
mean what they meant at the time in question (or most recently before that
time) rather than being absolutely fixed.
The standard abbreviation-list files have been changed to use this behavior
for abbreviations that have actually varied in meaning since 1970. The
old simple-numeric definitions are kept for abbreviations that have not
changed, since they are a bit faster to resolve.
While this is clearly a new feature, it seems necessary to back-patch it
into all active branches, because otherwise use of Russian zone
abbreviations is going to become even more problematic than it already was.
This change supersedes the changes in commit 513d06ded et al to modify the
fixed meanings of the Russian abbreviations; since we've not shipped that
yet, this will avoid an undesirably incompatible (not to mention incorrect)
change in behavior for timestamps between 2011 and 2014.
This patch makes some cosmetic changes in ecpglib to keep its usage of
datetime lookup tables as similar as possible to the backend code, but
doesn't do anything about the increasingly obsolete set of timezone
abbreviation definitions that are hard-wired into ecpglib. Whatever we
do about that will likely not be appropriate material for back-patching.
Also, a potential free() of a garbage pointer after an out-of-memory
failure in ecpglib has been fixed.
This patch also fixes pre-existing bugs in DetermineTimeZoneOffset() that
caused it to produce unexpected results near a timezone transition, if
both the "before" and "after" states are marked as standard time. We'd
only ever thought about or tested transitions between standard and DST
time, but that's not what's happening when a zone simply redefines their
base GMT offset.
In passing, update the SGML documentation to refer to the Olson/zoneinfo/
zic timezone database as the "IANA" database, since it's now being
maintained under the auspices of IANA.
The code wrote a value into the caller's field[] array before checking
to see if there was room, which of course is backwards. Per report from
Michael Paquier.
I fixed the equivalent bug in the backend's version of this code way back
in 630684d3a1, but failed to think about ecpg's copy. Fortunately
this doesn't look like it would be exploitable for anything worse than a
core dump: an external attacker would have no control over the single word
that gets written.
Programs need execute permission on a DLL file to load it. MSYS
"install" ignores the mode argument, and our Cygwin build statically
links libpq into programs. That explains the lack of buildfarm trouble.
Back-patch to 9.0 (all supported versions).
This reverts commit ece7aa8b0f.
It turns out that the %name-prefix syntax without "=" does not work
at all in pre-2.4 Bison. We are not prepared to make such a large
jump in minimum required Bison version just to suppress a warning
message in a version hardly any developers are using yet.
When 3.0 gets more popular, we'll figure out a way to deal with this.
In the meantime, BISONFLAGS=-Wno-deprecated is recommendable for
anyone using 3.0 who doesn't want to see the warning.
%name-prefix doesn't use an "=" sign according to the Bison docs, but it
silently accepted one anyway, until Bison 3.0. This was originally a
typo of mine in commit 012abebab1, and we
seem to have slavishly copied the error into all the other grammar files.
Per report from Vik Fearing; analysis by Peter Eisentraut.
Back-patch to all active branches, since somebody might try to build
a back branch with up-to-date tools.
Commit 4318daecc9 broke it. The change in
sub-second precision at extreme dates is normal. The inconsistent
truncation vs. rounding is essentially a bug, albeit a longstanding one.
Back-patch to 8.4, like the causative commit.
If the server sends a long stream of data, and the server + network are
consistently fast enough to force the recv() loop in pqReadData() to
iterate until libpq's input buffer is full, then upon processing the last
incomplete message in each bufferload we'd usually double the buffer size,
due to supposing that we didn't have enough room in the buffer to finish
collecting that message. After filling the newly-enlarged buffer, the
cycle repeats, eventually resulting in an out-of-memory situation (which
would be reported misleadingly as "lost synchronization with server").
Of course, we should not enlarge the buffer unless we still need room
after discarding already-processed messages.
This bug dates back quite a long time: pqParseInput3 has had the behavior
since perhaps 2003, getCopyDataMessage at least since commit 70066eb1a1
in 2008. Probably the reason it's not been isolated before is that in
common environments the recv() loop would always be faster than the server
(if on the same machine) or faster than the network (if not); or at least
it wouldn't be slower consistently enough to let the buffer ramp up to a
problematic size. The reported cases involve Windows, which perhaps has
different timing behavior than other platforms.
Per bug #7914 from Shin-ichi Morita, though this is different from his
proposed solution. Back-patch to all supported branches.
This was not changed in HEAD, but will be done later as part of a
pgindent run. Future pgindent runs will also do this.
Report by Tom Lane
Backpatch through all supported branches, but not HEAD
When array of char * was used as target for a FETCH statement returning more
than one row, it tried to store all the result in the first element. Instead it
should dump array of char pointers with right offset, use the address instead
of the value of the C variable while reading the array and treat such variable
as char **, instead of char * for pointer arithmetic.
Patch by Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Introduced in 585bca39: msgid is not used in the Windows code path.
Also adjust comments a tad (mostly to keep pgindent from messing it up).
David Rowley
Bind attempts to an LDAP server should time out after two seconds,
allowing additional lines in the service control file to be parsed
(which provide a fall back to a secondary LDAP server or default options).
The existing code failed to enforce that timeout during TCP connect,
resulting in a hang far longer than two seconds if the LDAP server
does not respond.
Laurenz Albe
Previously, in some places, socket creation errors were checked for
negative values, which is not true for Windows because sockets are
unsigned. This masked socket creation errors on Windows.
Backpatch through 9.0. 8.4 doesn't have the infrastructure to fix this.
"8" was correct back when "disable" was the longest allowed value, but
since "verify-full" was added, it should be "12". Given the lack of
complaints, I wouldn't be surprised if nobody is actually using these
values ... but still, if they're in the API, they should be right.
Noticed while pursuing a different problem. It's been wrong for quite
a long time, so back-patch to all supported branches.
Coverity identified a number of places in which it couldn't prove that a
string being copied into a fixed-size buffer would fit. We believe that
most, perhaps all of these are in fact safe, or are copying data that is
coming from a trusted source so that any overrun is not really a security
issue. Nonetheless it seems prudent to forestall any risk by using
strlcpy() and similar functions.
Fixes by Peter Eisentraut and Jozef Mlich based on Coverity reports.
In addition, fix a potential null-pointer-dereference crash in
contrib/chkpass. The crypt(3) function is defined to return NULL on
failure, but chkpass.c didn't check for that before using the result.
The main practical case in which this could be an issue is if libc is
configured to refuse to execute unapproved hashing algorithms (e.g.,
"FIPS mode"). This ideally should've been a separate commit, but
since it touches code adjacent to one of the buffer overrun changes,
I included it in this commit to avoid last-minute merge issues.
This issue was reported by Honza Horak.
Security: CVE-2014-0065 for buffer overruns, CVE-2014-0066 for crypt()
Many server functions use the MAXDATELEN constant to size a buffer for
parsing or displaying a datetime value. It was much too small for the
longest possible interval output and slightly too small for certain
valid timestamp input, particularly input with a long timezone name.
The long input was rejected needlessly; the long output caused
interval_out() to overrun its buffer. ECPG's pgtypes library has a copy
of the vulnerable functions, which bore the same vulnerabilities along
with some of its own. In contrast to the server, certain long inputs
caused stack overflow rather than failing cleanly. Back-patch to 8.4
(all supported versions).
Reported by Daniel Schüssler, reviewed by Tom Lane.
Security: CVE-2014-0063
In pqSendSome, if the connection is already closed at entry, discard any
queued output data before returning. There is no possibility of ever
sending the data, and anyway this corresponds to what we'd do if we'd
detected a hard error while trying to send(). This avoids possible
indefinite bloat of the output buffer if the application keeps trying
to send data (or even just keeps trying to do PQputCopyEnd, as psql
indeed will).
Because PQputCopyEnd won't transition out of PGASYNC_COPY_IN state
until it's successfully queued the COPY END message, and pqPutMsgEnd
doesn't distinguish a queuing failure from a pqSendSome failure,
this omission allowed an infinite loop in psql if the connection closure
occurred when we had at least 8K queued to send. It might be worth
refactoring so that we can make that distinction, but for the moment
the other changes made here seem to offer adequate defenses.
To guard against other variants of this scenario, do not allow
PQgetResult to return a PGRES_COPY_XXX result if the connection is
already known dead. Make sure it returns PGRES_FATAL_ERROR instead.
Per report from Stephen Frost. Back-patch to all active branches.
This has long been done by the MSVC build system, and has caused
confusion in the past when programs like psql have failed to start
because they can't find the DLL. If it's in the same directory as it now
will be they will find it.
Backpatch to all live branches.
In the platform that doesn't support Unix-domain socket, when
neither host nor hostaddr are specified, the default host
'localhost' is used to connect to the server and PQhost() must
return that, but it didn't. This patch fixes PQhost() so that
it returns the default host in that case.
Also this patch fixes PQhost() so that it doesn't return
Unix-domain socket directory path in the platform that doesn't
support Unix-domain socket.
Back-patch to all supported versions.
While working on most platforms the old way sometimes created alignment
problems. This should fix it. Also the regresion tests were updated to test for
the reported case.
Report and fix by MauMau <maumau307@gmail.com>
variables is varchar. This fixes this test case:
int main(void)
{
exec sql begin declare section;
varchar a[50], b[50];
exec sql end declare section;
return 0;
}
Since varchars are internally turned into custom structs and
the type name is emitted for these variable declarations,
the preprocessed code previously had:
struct varchar_1 { ... } a _,_ struct varchar_2 { ... } b ;
The comma in the generated C file was a syntax error.
There are no regression test changes since it's not exercised.
Patch by Boszormenyi Zoltan <zb@cybertec.at>
In libpq, we set up and pass to OpenSSL callback routines to handle
locking. When we run out of SSL connections, we try to clean things
up by de-registering the hooks. Unfortunately, we had a few calls
into the OpenSSL library after these hooks were de-registered during
SSL cleanup which lead to deadlocking. This moves the thread callback
cleanup to be after all SSL-cleanup related OpenSSL library calls.
I've been unable to reproduce the deadlock with this fix.
In passing, also move the close_SSL call to be after unlocking our
ssl_config mutex when in a failure state. While it looks pretty
unlikely to be an issue, it could have resulted in deadlocks if we
ended up in this code path due to something other than SSL_new
failing. Thanks to Heikki for pointing this out.
Back-patch to all supported versions; note that the close_SSL issue
only goes back to 9.0, so that hunk isn't included in the 8.4 patch.
Initially found and reported by Vesa-Matti J Kari; many thanks to
both Heikki and Andres for their help running down the specific
issue and reviewing the patch.
