pgsql: Reject "23:59:60.nnn" in datetime input. - Mailing list pgsql-committers

From Tom Lane
Subject pgsql: Reject "23:59:60.nnn" in datetime input.
Date
Msg-id E1jgwhG-0002Cy-DE@gemulon.postgresql.org
Whole thread Raw
List pgsql-committers
Reject "23:59:60.nnn" in datetime input.

It's intentional that we don't allow values greater than 24 hours,
while we do allow "24:00:00" as well as "23:59:60" as inputs.
However, the range check was miscoded in such a way that it would
accept "23:59:60.nnn" with a nonzero fraction.  For time or timetz,
the stored result would then be greater than "24:00:00" which would
fail dump/reload, not to mention possibly confusing other operations.

Fix by explicitly calculating the result and making sure it does not
exceed 24 hours.  (This calculation is redundant with what will happen
later in tm2time or tm2timetz.  Maybe someday somebody will find that
annoying enough to justify refactoring to avoid the duplication; but
that seems too invasive for a back-patched bug fix, and the cost is
probably unmeasurable anyway.)

Note that this change also rejects such input as the time portion
of a timestamp(tz) value.

Back-patch to v10.  The bug is far older, but to change this pre-v10
we'd need to ensure that the logic behaves sanely with float timestamps,
which is possibly nontrivial due to roundoff considerations.
Doesn't really seem worth troubling with.

Per report from Christoph Berg.

Discussion: https://postgr.es/m/20200520125807.GB296739@msg.df7cb.de

Branch
------
REL_10_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/b2c64f571db474a4094232eba604f7a6b4db124e

Modified Files
--------------
src/backend/utils/adt/date.c         | 70 ++++++++++++++++++++++++++++++++----
src/backend/utils/adt/datetime.c     | 23 +++---------
src/backend/utils/adt/timestamp.c    | 17 +++------
src/include/utils/date.h             |  2 ++
src/test/regress/expected/time.out   | 41 +++++++++++++++++++++
src/test/regress/expected/timetz.out | 41 +++++++++++++++++++++
src/test/regress/sql/time.sql        | 10 ++++++
src/test/regress/sql/timetz.sql      | 10 ++++++
8 files changed, 176 insertions(+), 38 deletions(-)


pgsql-committers by date:

Previous
From: Peter Eisentraut
Date:
Subject: pgsql: psql: Clean up terminology in \dAp command
Next
From: Tom Lane
Date:
Subject: pgsql: Add missing #include.