postgresql/src
Tom Lane a18328bb33 Fix jsonb subscripting to cope with toasted subscript values.
jsonb_get_element() was incautious enough to use VARDATA() and
VARSIZE() directly on an arbitrary text Datum.  That of course
fails if the Datum is short-header, compressed, or out-of-line.
The typical result would be failing to match any element of a
jsonb object, though matching the wrong one seems possible as well.

setPathObject() was slightly brighter, in that it used VARDATA_ANY
and VARSIZE_ANY_EXHDR, but that only kept it out of trouble for
short-header Datums.  push_path() had the same issue.  This could
result in faulty subscripted insertions, though keys long enough to
cause a problem are likely rare in the wild.

Having seen these, I looked around for unsafe usages in the rest
of the adt/json* files.  There are a couple of places where it's not
immediately obvious that the Datum can't be compressed or out-of-line,
so I added pg_detoast_datum_packed() to cope if it is.  Also, remove
some other usages of VARDATA/VARSIZE on Datums we just extracted from
a text array.  Those aren't actively broken, but they will become so
if we ever start allowing short-header array elements, which does not
seem like a terribly unreasonable thing to do.  In any case they are
not great coding examples, and they could also do with comments
pointing out that we're assuming we don't need pg_detoast_datum_packed.

Per report from exe-dealer@yandex.ru.  Patch by me, but thanks to
David Johnston for initial investigation.  Back-patch to v14 where
jsonb subscripting was introduced.

Discussion: https://postgr.es/m/205321670615953@mail.yandex.ru
2022-12-12 16:17:49 -05:00
..
backend Fix jsonb subscripting to cope with toasted subscript values. 2022-12-12 16:17:49 -05:00
bin Fix psql's \sf and \ef for new-style SQL functions. 2022-12-02 14:24:44 -05:00
common Change some errdetail() to errdetail_internal() 2022-09-28 17:14:53 +02:00
fe_utils Use correct connection for cancellation in frontend's parallel slots 2022-08-27 15:22:11 +09:00
include Remove new structure member from ResultRelInfo. 2022-12-08 16:15:03 +09:00
interfaces Fix comment in fe-auth-scram.c 2022-11-30 08:38:30 +09:00
makefiles Add NO_INSTALL option to pgxs 2021-05-27 13:58:29 +02:00
pl Allow building with MSVC and Strawberry perl 2022-11-25 15:37:33 -05:00
port Re-allow building on Microsoft Visual Studio 2013. 2022-11-10 10:23:49 -05:00
template On NetBSD, force dynamic symbol resolution at postmaster start. 2022-08-30 17:29:03 -04:00
test Fix jsonb subscripting to cope with toasted subscript values. 2022-12-12 16:17:49 -05:00
timezone Update time zone data files to tzdata release 2022f. 2022-11-01 17:08:58 -04:00
tools Fix binary mismatch for MSVC plperl vs gcc built perl libs 2022-11-27 09:18:20 -05:00
tutorial Doc: sync src/tutorial/basics.source with SGML documentation. 2022-11-19 13:09:14 -05:00
.gitignore
DEVELOPERS
Makefile Remove the option to build thread_test.c outside configure. 2020-10-21 12:08:48 -04:00
Makefile.global.in Prevent port collisions between concurrent TAP tests 2022-11-22 10:51:55 -05:00
Makefile.shlib AIX: Fix missing libpq symbols by respecting SHLIB_EXPORTS. 2021-09-06 11:28:02 -07:00
nls-global.mk Add errhint_plural() function and make use of it 2021-03-31 09:16:25 +02:00