From 72d0c135bd7a9ab4602ea1bece0054bb1e8d372d Mon Sep 17 00:00:00 2001 From: Dean Rasheed Date: Sat, 18 Nov 2023 14:46:02 +0000 Subject: [PATCH] Guard against overflow in interval_mul() and interval_div(). Commits 146604ec43 and a898b409f6 added overflow checks to interval_mul(), but not to interval_div(), which contains almost identical code, and so is susceptible to the same kinds of overflows. In addition, those checks did not catch all possible overflow conditions. Add additional checks to the "cascade down" code in interval_mul(), and copy all the overflow checks over to the corresponding code in interval_div(), so that they both generate "interval out of range" errors, rather than returning bogus results. Given that these errors are relatively easy to hit, back-patch to all supported branches. Per bug #18200 from Alexander Lakhin, and subsequent investigation. Discussion: https://postgr.es/m/18200-5ea288c7b2d504b1%40postgresql.org --- src/backend/utils/adt/timestamp.c | 69 ++++++++++++++++++-------- src/test/regress/expected/interval.out | 13 +++++ src/test/regress/sql/interval.sql | 8 +++ 3 files changed, 69 insertions(+), 21 deletions(-) diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c index 0e50aaec5a5..6d455cdc9de 100644 --- a/src/backend/utils/adt/timestamp.c +++ b/src/backend/utils/adt/timestamp.c @@ -3315,19 +3315,13 @@ interval_mul(PG_FUNCTION_ARGS) result = (Interval *) palloc(sizeof(Interval)); result_double = span->month * factor; - if (isnan(result_double) || - result_double > INT_MAX || result_double < INT_MIN) - ereport(ERROR, - (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), - errmsg("interval out of range"))); + if (isnan(result_double) || !FLOAT8_FITS_IN_INT32(result_double)) + goto out_of_range; result->month = (int32) result_double; result_double = span->day * factor; - if (isnan(result_double) || - result_double > INT_MAX || result_double < INT_MIN) - ereport(ERROR, - (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), - errmsg("interval out of range"))); + if (isnan(result_double) || !FLOAT8_FITS_IN_INT32(result_double)) + goto out_of_range; result->day = (int32) result_double; /* @@ -3361,20 +3355,30 @@ interval_mul(PG_FUNCTION_ARGS) */ if (fabs(sec_remainder) >= SECS_PER_DAY) { - result->day += (int) (sec_remainder / SECS_PER_DAY); + if (pg_add_s32_overflow(result->day, + (int) (sec_remainder / SECS_PER_DAY), + &result->day)) + goto out_of_range; sec_remainder -= (int) (sec_remainder / SECS_PER_DAY) * SECS_PER_DAY; } /* cascade units down */ - result->day += (int32) month_remainder_days; + if (pg_add_s32_overflow(result->day, (int32) month_remainder_days, + &result->day)) + goto out_of_range; result_double = rint(span->time * factor + sec_remainder * USECS_PER_SEC); if (isnan(result_double) || !FLOAT8_FITS_IN_INT64(result_double)) - ereport(ERROR, - (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), - errmsg("interval out of range"))); + goto out_of_range; result->time = (int64) result_double; PG_RETURN_INTERVAL_P(result); + +out_of_range: + ereport(ERROR, + errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), + errmsg("interval out of range")); + + PG_RETURN_NULL(); /* keep compiler quiet */ } Datum @@ -3393,7 +3397,8 @@ interval_div(PG_FUNCTION_ARGS) Interval *span = PG_GETARG_INTERVAL_P(0); float8 factor = PG_GETARG_FLOAT8(1); double month_remainder_days, - sec_remainder; + sec_remainder, + result_double; int32 orig_month = span->month, orig_day = span->day; Interval *result; @@ -3405,8 +3410,15 @@ interval_div(PG_FUNCTION_ARGS) (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); - result->month = (int32) (span->month / factor); - result->day = (int32) (span->day / factor); + result_double = span->month / factor; + if (isnan(result_double) || !FLOAT8_FITS_IN_INT32(result_double)) + goto out_of_range; + result->month = (int32) result_double; + + result_double = span->day / factor; + if (isnan(result_double) || !FLOAT8_FITS_IN_INT32(result_double)) + goto out_of_range; + result->day = (int32) result_double; /* * Fractional months full days into days. See comment in interval_mul(). @@ -3418,15 +3430,30 @@ interval_div(PG_FUNCTION_ARGS) sec_remainder = TSROUND(sec_remainder); if (fabs(sec_remainder) >= SECS_PER_DAY) { - result->day += (int) (sec_remainder / SECS_PER_DAY); + if (pg_add_s32_overflow(result->day, + (int) (sec_remainder / SECS_PER_DAY), + &result->day)) + goto out_of_range; sec_remainder -= (int) (sec_remainder / SECS_PER_DAY) * SECS_PER_DAY; } /* cascade units down */ - result->day += (int32) month_remainder_days; - result->time = rint(span->time / factor + sec_remainder * USECS_PER_SEC); + if (pg_add_s32_overflow(result->day, (int32) month_remainder_days, + &result->day)) + goto out_of_range; + result_double = rint(span->time / factor + sec_remainder * USECS_PER_SEC); + if (isnan(result_double) || !FLOAT8_FITS_IN_INT64(result_double)) + goto out_of_range; + result->time = (int64) result_double; PG_RETURN_INTERVAL_P(result); + +out_of_range: + ereport(ERROR, + errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE), + errmsg("interval out of range")); + + PG_RETURN_NULL(); /* keep compiler quiet */ } diff --git a/src/test/regress/expected/interval.out b/src/test/regress/expected/interval.out index 28b71d96817..9fc9b0f087f 100644 --- a/src/test/regress/expected/interval.out +++ b/src/test/regress/expected/interval.out @@ -388,6 +388,19 @@ SELECT * FROM INTERVAL_TBL; @ 5 mons 12 hours (10 rows) +-- multiplication and division overflow test cases +SELECT '3000000 months'::interval * 1000; +ERROR: interval out of range +SELECT '3000000 months'::interval / 0.001; +ERROR: interval out of range +SELECT '3000000 days'::interval * 1000; +ERROR: interval out of range +SELECT '3000000 days'::interval / 0.001; +ERROR: interval out of range +SELECT '1 month 2146410 days'::interval * 1000.5002; +ERROR: interval out of range +SELECT '4611686018427387904 usec'::interval / 0.1; +ERROR: interval out of range -- test avg(interval), which is somewhat fragile since people have been -- known to change the allowed input syntax for type interval without -- updating pg_aggregate.agginitval diff --git a/src/test/regress/sql/interval.sql b/src/test/regress/sql/interval.sql index 56feda1a3d8..040268db024 100644 --- a/src/test/regress/sql/interval.sql +++ b/src/test/regress/sql/interval.sql @@ -136,6 +136,14 @@ SET IntervalStyle to postgres_verbose; SELECT * FROM INTERVAL_TBL; +-- multiplication and division overflow test cases +SELECT '3000000 months'::interval * 1000; +SELECT '3000000 months'::interval / 0.001; +SELECT '3000000 days'::interval * 1000; +SELECT '3000000 days'::interval / 0.001; +SELECT '1 month 2146410 days'::interval * 1000.5002; +SELECT '4611686018427387904 usec'::interval / 0.1; + -- test avg(interval), which is somewhat fragile since people have been -- known to change the allowed input syntax for type interval without -- updating pg_aggregate.agginitval