On Mon, Feb 14, 2022 at 7:59 PM Nathan Bossart <nathandboss...@gmail.com> wrote: > I think it's possible to avoid overflow in justify_interval() in some cases > by pre-justifying the days. I've attached a patch to demonstrate. > > -- > Nathan Bossart > Amazon Web Services: https://aws.amazon.com
Good catch, I didn't think about that. Though if you are pre-justifying the days, then I don't think it's possible for the second addition to days to overflow. The maximum amount the days field could be after the first justification is 29. I think we can simplify it further to the attached patch. - Joe
From 8ff8302b90c790d967f770286dfa54432f63662c Mon Sep 17 00:00:00 2001 From: Joseph Koshakow <kosh...@gmail.com> Date: Sun, 13 Feb 2022 13:26:16 -0500 Subject: [PATCH] Check for overflow in justify_interval functions justify_interval, justify_hours, and justify_days didn't check for overflow when moving hours to days or days to hours. This commit adds check for overflow and returns an appropriate error. Signed-off-by: Joseph Koshakow <kosh...@gmail.com> --- src/backend/utils/adt/timestamp.c | 29 ++++++++++++++++++--- src/test/regress/expected/interval.out | 36 ++++++++++++++++++++++++++ src/test/regress/sql/interval.sql | 12 +++++++++ 3 files changed, 73 insertions(+), 4 deletions(-) diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c index 36f8a84bcc..ce11fcbeef 100644 --- a/src/backend/utils/adt/timestamp.c +++ b/src/backend/utils/adt/timestamp.c @@ -2717,12 +2717,27 @@ interval_justify_interval(PG_FUNCTION_ARGS) result->day = span->day; result->time = span->time; + /* pre-justify days if it might prevent overflow */ + if ((result->day > 0 && result->time > 0) || + (result->day < 0 && result->time < 0)) + { + wholemonth = result->day / DAYS_PER_MONTH; + result->day -= wholemonth * DAYS_PER_MONTH; + if (pg_add_s32_overflow(result->month, wholemonth, &result->month)) + ereport(ERROR, + (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), + errmsg("interval out of range"))); + } + TMODULO(result->time, wholeday, USECS_PER_DAY); - result->day += wholeday; /* could overflow... */ + result->day += wholeday; wholemonth = result->day / DAYS_PER_MONTH; result->day -= wholemonth * DAYS_PER_MONTH; - result->month += wholemonth; + if (pg_add_s32_overflow(result->month, wholemonth, &result->month)) + ereport(ERROR, + (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), + errmsg("interval out of range"))); if (result->month > 0 && (result->day < 0 || (result->day == 0 && result->time < 0))) @@ -2772,7 +2787,10 @@ interval_justify_hours(PG_FUNCTION_ARGS) result->time = span->time; TMODULO(result->time, wholeday, USECS_PER_DAY); - result->day += wholeday; /* could overflow... */ + if (pg_add_s32_overflow(result->day, wholeday, &result->day)) + ereport(ERROR, + (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), + errmsg("interval out of range"))); if (result->day > 0 && result->time < 0) { @@ -2808,7 +2826,10 @@ interval_justify_days(PG_FUNCTION_ARGS) wholemonth = result->day / DAYS_PER_MONTH; result->day -= wholemonth * DAYS_PER_MONTH; - result->month += wholemonth; + if (pg_add_s32_overflow(result->month, wholemonth, &result->month)) + ereport(ERROR, + (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), + errmsg("interval out of range"))); if (result->month > 0 && result->day < 0) { diff --git a/src/test/regress/expected/interval.out b/src/test/regress/expected/interval.out index accd4a7d90..146f7c55d0 100644 --- a/src/test/regress/expected/interval.out +++ b/src/test/regress/expected/interval.out @@ -396,6 +396,10 @@ SELECT justify_days(interval '6 months 36 days 5 hours 4 minutes 3 seconds') as @ 7 mons 6 days 5 hours 4 mins 3 secs (1 row) +SELECT justify_hours(interval '2147483647 days 24 hrs'); +ERROR: interval out of range +SELECT justify_days(interval '2147483647 months 30 days'); +ERROR: interval out of range -- test justify_interval() SELECT justify_interval(interval '1 month -1 hour') as "1 month -1 hour"; 1 month -1 hour @@ -403,6 +407,38 @@ SELECT justify_interval(interval '1 month -1 hour') as "1 month -1 hour"; @ 29 days 23 hours (1 row) +SELECT justify_interval(interval '2147483647 days 24 hrs'); + justify_interval +------------------------------- + @ 5965232 years 4 mons 8 days +(1 row) + +SELECT justify_interval(interval '-2147483648 days -24 hrs'); + justify_interval +----------------------------------- + @ 5965232 years 4 mons 9 days ago +(1 row) + +SELECT justify_interval(interval '2147483647 months 30 days'); +ERROR: interval out of range +SELECT justify_interval(interval '-2147483648 months -30 days'); +ERROR: interval out of range +SELECT justify_interval(interval '2147483647 months 30 days -24 hrs'); + justify_interval +---------------------------------- + @ 178956970 years 7 mons 29 days +(1 row) + +SELECT justify_interval(interval '-2147483648 months -30 days 24 hrs'); + justify_interval +-------------------------------------- + @ 178956970 years 8 mons 29 days ago +(1 row) + +SELECT justify_interval(interval '2147483647 months -30 days 1440 hrs'); +ERROR: interval out of range +SELECT justify_interval(interval '-2147483648 months 30 days -1440 hrs'); +ERROR: interval out of range -- test fractional second input, and detection of duplicate units SET DATESTYLE = 'ISO'; SET IntervalStyle TO postgres; diff --git a/src/test/regress/sql/interval.sql b/src/test/regress/sql/interval.sql index 6d532398bd..c31f0eec05 100644 --- a/src/test/regress/sql/interval.sql +++ b/src/test/regress/sql/interval.sql @@ -149,10 +149,22 @@ select '100000000y 10mon -1000000000d -100000h -10min -10.000001s ago'::interval SELECT justify_hours(interval '6 months 3 days 52 hours 3 minutes 2 seconds') as "6 mons 5 days 4 hours 3 mins 2 seconds"; SELECT justify_days(interval '6 months 36 days 5 hours 4 minutes 3 seconds') as "7 mons 6 days 5 hours 4 mins 3 seconds"; +SELECT justify_hours(interval '2147483647 days 24 hrs'); +SELECT justify_days(interval '2147483647 months 30 days'); + -- test justify_interval() SELECT justify_interval(interval '1 month -1 hour') as "1 month -1 hour"; +SELECT justify_interval(interval '2147483647 days 24 hrs'); +SELECT justify_interval(interval '-2147483648 days -24 hrs'); +SELECT justify_interval(interval '2147483647 months 30 days'); +SELECT justify_interval(interval '-2147483648 months -30 days'); +SELECT justify_interval(interval '2147483647 months 30 days -24 hrs'); +SELECT justify_interval(interval '-2147483648 months -30 days 24 hrs'); +SELECT justify_interval(interval '2147483647 months -30 days 1440 hrs'); +SELECT justify_interval(interval '-2147483648 months 30 days -1440 hrs'); + -- test fractional second input, and detection of duplicate units SET DATESTYLE = 'ISO'; SET IntervalStyle TO postgres; -- 2.25.1