Subject: pgsql: ecpg: Fix zero-termination of string generated by intoasc()

From: Michael Paquier <[email-masked]>
Date: Mon, 19 Feb 2024 02:39:20 +0000

ecpg: Fix zero-termination of string generated by intoasc()

intoasc(), a wrapper for PGTYPESinterval_to_asc that converts an
interval to its textual representation, used a plain memcpy() when
copying its result.  This could miss a zero-termination in the result
string, leading to an incorrect result.

The routines in informix.c do not provide the length of their result
buffer, which would allow a replacement of strcpy() to safer strlcpy()
calls, but this requires an ABI breakage and that cannot happen in
back-branches.

Author: Oleg Tselebrovskiy
Reviewed-by: Ashutosh Bapat
Discussion: https://postgr.es/m/[email-masked]
Backpatch-through: 12

Branch
------
REL_13_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/c031ce97b561e79d3d91de9334ced561cc6c2571

Modified Files
--------------
src/interfaces/ecpg/compatlib/informix.c           |  2 +-
.../ecpg/test/compat_informix/.gitignore           |  2 ++
src/interfaces/ecpg/test/compat_informix/Makefile  |  3 +-
.../ecpg/test/compat_informix/intoasc.pgc          | 21 ++++++++++++
src/interfaces/ecpg/test/ecpg_schedule             |  1 +
.../ecpg/test/expected/compat_informix-intoasc.c   | 40 ++++++++++++++++++++++
.../test/expected/compat_informix-intoasc.stderr   |  0
.../test/expected/compat_informix-intoasc.stdout   |  2 ++
8 files changed, 69 insertions(+), 2 deletions(-)