Stowage/go
2
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-12-08 06:10:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

time: check int64 overflow in Time.addSec

Browse source 
Change-Id: Ibbed54239228e7ea31ef5978d427425899c3b943
Reviewed-on: https://go-review.googlesource.com/c/go/+/300890
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Baokun Lee <bk@golangcn.org>
This commit is contained in:
Andy Pan 2021-03-12 19:40:46 +08:00 • committed by Ian Lance Taylor
parent 5423f6023c
commit a5df88355c
4 changed files with 38 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

1
src/time/export_test.go
View file

@ -51,6 +51,7 @@ const (
RuleJulian = RuleKind(ruleJulian) RuleJulian = RuleKind(ruleJulian)
RuleDOY = RuleKind(ruleDOY) RuleDOY = RuleKind(ruleDOY)
RuleMonthWeekDay = RuleKind(ruleMonthWeekDay) RuleMonthWeekDay = RuleKind(ruleMonthWeekDay)
UnixToInternal = unixToInternal
) )
type Rule struct { type Rule struct {

2
src/time/internal_test.go
View file

@ -62,4 +62,6 @@ func CheckRuntimeTimerPeriodOverflow() {
var ( var (
MinMonoTime = Time{wall: 1 << 63, ext: -1 << 63, loc: UTC} MinMonoTime = Time{wall: 1 << 63, ext: -1 << 63, loc: UTC}
MaxMonoTime = Time{wall: 1 << 63, ext: 1<<63 - 1, loc: UTC} MaxMonoTime = Time{wall: 1 << 63, ext: 1<<63 - 1, loc: UTC}
NotMonoNegativeTime = Time{wall: 0, ext: -1<<63 + 50}
) )

11
src/time/time.go
View file

@ -189,8 +189,15 @@ func (t *Time) addSec(d int64) {
t.stripMono() t.stripMono()
} }
// TODO: Check for overflow. // Check if the sum of t.ext and d overflows and handle it properly.
t.ext += d sum := t.ext + d
if (sum > t.ext) == (d > 0) {
t.ext = sum
} else if d > 0 {
t.ext = 1<<63 - 1
} else {
t.ext = -(1<<63 - 1)
}
} }
// setLoc sets the location associated with the time. // setLoc sets the location associated with the time.

27
src/time/time_test.go
View file

@ -1481,7 +1481,7 @@ func TestTimeIsDST(t *testing.T) {
tzFixed := FixedZone("FIXED_TIME", 12345) tzFixed := FixedZone("FIXED_TIME", 12345)
tests := [...]struct { tests := [...]struct {
time Time time Time
want bool want bool
}{ }{
0: {Date(2009, 1, 1, 12, 0, 0, 0, UTC), false}, 0: {Date(2009, 1, 1, 12, 0, 0, 0, UTC), false},
@ -1501,3 +1501,28 @@ func TestTimeIsDST(t *testing.T) {
} }
} }
} }
func TestTimeAddSecOverflow(t *testing.T) {
// Test it with positive delta.
var maxInt64 int64 = 1<<63 - 1
timeExt := maxInt64 - UnixToInternal - 50
notMonoTime := Unix(timeExt, 0)
for i := int64(0); i < 100; i++ {
sec := notMonoTime.Unix()
notMonoTime = notMonoTime.Add(Duration(i * 1e9))
if newSec := notMonoTime.Unix(); newSec != sec+i && newSec+UnixToInternal != maxInt64 {
t.Fatalf("time ext: %d overflows with positive delta, overflow threshold: %d", newSec, maxInt64)
}
}
// Test it with negative delta.
maxInt64 = -maxInt64
notMonoTime = NotMonoNegativeTime
for i := int64(0); i > -100; i-- {
sec := notMonoTime.Unix()
notMonoTime = notMonoTime.Add(Duration(i * 1e9))
if newSec := notMonoTime.Unix(); newSec != sec+i && newSec+UnixToInternal != maxInt64 {
t.Fatalf("time ext: %d overflows with positive delta, overflow threshold: %d", newSec, maxInt64)
}
}
}