Since the fixes for CVE-2018-1058, we've advised people to schema-qualify
function references in order to fix failures in code that executes under
a minimal search_path setting. However, that's insufficient to make the
single-argument form of unaccent() work, because it looks up the "unaccent"
text search dictionary using the search path.
The most expedient answer seems to be to remove the search_path dependency
by making it look in the same schema that the unaccent() function itself
is declared in. This will definitely work for the normal usage of this
function with the unaccent dictionary provided by the extension.
It's barely possible that there are people who were relying on the
search-path-dependent behavior to select other dictionaries with the same
name; but if there are any such people at all, they can still get that
behavior by writing unaccent('unaccent', ...), or possibly
unaccent('unaccent'::text::regdictionary, ...) if the lookup has to be
postponed to runtime.
Per complaint from Gunnlaugur Thor Briem. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/CAPs+M8LCex6d=DeneofdsoJVijaG59m9V0ggbb3pOH7hZO4+cQ@mail.gmail.com
The output buffer size in unaccent_lexize() was calculated as input string
length times pg_database_encoding_max_length(), which effectively assumes
that replacement strings aren't more than one character. While that was
all that we previously documented it to support, the code actually has
always allowed replacement strings of arbitrary length; so if you tried
to make use of longer strings, you were at risk of buffer overrun. To fix,
use an expansible StringInfo buffer instead of trying to determine the
maximum space needed a-priori.
This would be a security issue if unaccent rules files could be installed
by unprivileged users; but fortunately they can't, so in the back branches
the problem can be labeled as improper configuration by a superuser.
Nonetheless, a memory stomp isn't a nice way of reacting to improper
configuration, so let's back-patch the fix.
Make it use t_isspace() to identify whitespace, rather than relying on
sscanf which is known to get it wrong on some platform/locale combinations.
Get rid of fixed-size buffers. Make it actually continue to parse the file
after ignoring a line with untranslatable characters, as was obviously
intended.
The first of these issues is per gripe from J Smith, though not exactly
either of his proposed patches.
- Rename TSParserGetPrsid to get_ts_parser_oid.
- Rename TSDictionaryGetDictid to get_ts_dict_oid.
- Rename TSTemplateGetTmplid to get_ts_template_oid.
- Rename TSConfigGetCfgid to get_ts_config_oid.
- Rename FindConversionByName to get_conversion_oid.
- Rename GetConstraintName to get_constraint_oid.
- Add new functions get_opclass_oid, get_opfamily_oid, get_rewrite_oid,
get_rewrite_oid_without_relid, get_trigger_oid, and get_cast_oid.
The name of each function matches the corresponding catalog.
Thanks to KaiGai Kohei for the review.