Widen the postgres interval month arithmetic - #5204
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| Ok(Duration::days(days as i64) + Duration::microseconds(interval.microseconds)) | ||
| // widened, since any `i32` month and day pair fits `i64` days and chrono | ||
| let days = | ||
| i64::from(interval.months) * i64::from(DAYS_PER_MONTH) + i64::from(interval.days); |
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Just change the DAYS_PER_MONTH to be i64.
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FromSql<Interval, Pg> for chrono::Durationcomputesinterval.months * DAYS_PER_MONTH + interval.daysini32, and all three fields arrive off the wire, so a well formed 16 byte interval is enough to overflow it. With debug assertions the conversion panics, and without them it wraps and the caller gets a plausible looking duration that is wrong, often with the opposite sign, where one month together withi32::MAXdays reads as-185542584681600seconds where the true value is185542589692800.It does not take an absurd month count either, one month is already enough once the day count is large. This is the arithmetic one line past the length check fixed in #5194, which does not touch it.
Counting the days in
i64removes the overflow without narrowing what is accepted, as the widest interval is about 66678745079 days, whilechrono::Durationreaches 106751991167.This came out of a fuzzer I am writing for diesel's deserialization code.