An incorrectly-encoded multibyte character near the end of a string
could cause various processing loops to run past the string's
terminating NUL, with results ranging from no detectable issue to
a program crash, depending on what happens to be in the following
memory.
This isn't an issue in the server, because we take care to verify
the encoding of strings before doing any interesting processing
on them. However, that lack of care leaked into client-side code
which shouldn't assume that anyone has validated the encoding of
its input.
Although this is certainly a bug worth fixing, the PG security team
elected not to regard it as a security issue, primarily because
any untrusted text should be sanitized by PQescapeLiteral or
the like before being incorporated into a SQL or psql command.
(If an app fails to do so, the same technique can be used to
cause SQL injection, with probably much more dire consequences
than a mere client-program crash.) Those functions were already
made proof against this class of problem, cf CVE-2006-2313.
To fix, invent PQmblenBounded() which is like PQmblen() except it
won't return more than the number of bytes remaining in the string.
In HEAD we can make this a new libpq function, as PQmblen() is.
It seems imprudent to change libpq's API in stable branches though,
so in the back branches define PQmblenBounded as a macro in the files
that need it. (Note that just changing PQmblen's behavior would not
be a good idea; notably, it would completely break the escaping
functions' defense against this exact problem. So we just want a
version for those callers that don't have any better way of handling
this issue.)
Per private report from houjingyi. Back-patch to all supported branches.
The Readline library contains a fair amount of knowledge about how to
tab-complete filenames, but it turns out that that doesn't work too well
unless we follow its expectation that we use its filename quoting hooks
to quote and de-quote filenames. We were trying to do such quote handling
within complete_from_files(), and that's still what we have to do if we're
using libedit, which lacks those hooks. But for Readline, it works a lot
better if we tell Readline that single-quote is a quoting character and
then provide hooks that know the details of the quoting rules for SQL
and psql meta-commands.
Hence, resurrect the quoting hook functions that existed in the original
version of tab-complete.c (and were disabled by commit f6689a328 because
they "didn't work so well yet"), and whack on them until they do seem to
work well.
Notably, this fixes bug #16059 from Steven Winfield, who pointed out
that the previous coding would strip quote marks from filenames in SQL
COPY commands, even though they're syntactically necessary there.
Now, we not only don't do that, but we'll add a quote mark when you
tab-complete, even if you didn't type one.
Getting this to work across a range of libedit versions (and, to a
lesser extent, libreadline versions) was depressingly difficult.
It will be interesting to see whether the new regression test cases
pass everywhere in the buildfarm.
Some future patch might try to handle quoted SQL identifiers with
similar explicit quoting/dequoting logic, but that's for another day.
Patch by me, reviewed by Peter Eisentraut.
Discussion: https://postgr.es/m/16059-8836946734c02b84@postgresql.org
The lower case spellings are C and C++ standard and are used in most
parts of the PostgreSQL sources. The upper case spellings are only used
in some files/modules. So standardize on the standard spellings.
The APIs for ICU, Perl, and Windows define their own TRUE and FALSE, so
those are left as is when using those APIs.
In code comments, we use the lower-case spelling for the C concepts and
keep the upper-case spelling for the SQL concepts.
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
The new indent version includes numerous fixes thanks to Piotr Stefaniak.
The main changes visible in this commit are:
* Nicer formatting of function-pointer declarations.
* No longer unexpectedly removes spaces in expressions using casts,
sizeof, or offsetof.
* No longer wants to add a space in "struct structname *varname", as
well as some similar cases for const- or volatile-qualified pointers.
* Declarations using PG_USED_FOR_ASSERTS_ONLY are formatted more nicely.
* Fixes bug where comments following declarations were sometimes placed
with no space separating them from the code.
* Fixes some odd decisions for comments following case labels.
* Fixes some cases where comments following code were indented to less
than the expected column 33.
On the less good side, it now tends to put more whitespace around typedef
names that are not listed in typedefs.list. This might encourage us to
put more effort into typedef name collection; it's not really a bug in
indent itself.
There are more changes coming after this round, having to do with comment
indentation and alignment of lines appearing within parentheses. I wanted
to limit the size of the diffs to something that could be reviewed without
one's eyes completely glazing over, so it seemed better to split up the
changes as much as practical.
Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
This includes backend "COPY TO/FROM PROGRAM '...'" syntax, and corresponding
psql \copy syntax. Like with reading/writing files, the backend version is
superuser-only, and in the psql version, the program is run in the client.
In the passing, the psql \copy STDIN/STDOUT syntax is subtly changed: if you
the stdin/stdout is quoted, it's now interpreted as a filename. For example,
"\copy foo from 'stdin'" now reads from a file called 'stdin', not from
standard input. Before this, there was no way to specify a filename called
stdin, stdout, pstdin or pstdout.
This creates a new function in pgport, wait_result_to_str(), which can
be used to convert the exit status of a process, as returned by wait(3),
to a human-readable string.
Etsuro Fujita, reviewed by Amit Kapila.
psql backslash commands that deal with file or directory names require
quotes around those that have spaces, single quotes, or backslashes.
However, tab-completing such names does not provide said quotes, and is
thus almost useless with them.
This patch fixes the problem by having a wrapper function around
rl_filename_completion_function that dequotes on input and quotes on
output. This eases dealing with such names.
Author: Noah Misch
little more sane. Some parts of the code was using a static function
xmalloc() that did safe memory allocation (where "safe" means "bail
out on OOM"), but most of it was just invoking calloc() or malloc()
directly. Now almost everything invokes xmalloc() or xcalloc().
a column list. Bring its parsing of quoted names and quoted strings
somewhat up to speed --- I believe it now handles all non-error cases
the same way the backend would, but weird boundary conditions are not
necessarily done the same way.
are now separate files "postgres.h" and "postgres_fe.h", which are meant
to be the primary include files for backend .c files and frontend .c files
respectively. By default, only include files meant for frontend use are
installed into the installation include directory. There is a new make
target 'make install-all-headers' that adds the whole content of the
src/include tree to the installed fileset, for use by people who want to
develop server-side code without keeping the complete source tree on hand.
Cleaned up a whole lot of crufty and inconsistent header inclusions.
Bruce Momjian
Tom Lane
Peter Eisentraut
Heikki Linnakangas
Andrew Dunstan
Alvaro Herrera
Magnus Hagander
Neil Conway
PostgreSQL Daemon
Tatsuo Ishii