diff options
| -rw-r--r-- | src/pkg/runtime/time.goc | 5 | ||||
| -rw-r--r-- | src/pkg/time/sleep_test.go | 20 |
2 files changed, 25 insertions, 0 deletions
diff --git a/src/pkg/runtime/time.goc b/src/pkg/runtime/time.goc index 6de989f515..be0c1f83d4 100644 --- a/src/pkg/runtime/time.goc +++ b/src/pkg/runtime/time.goc @@ -131,6 +131,11 @@ runtime·deltimer(Timer *t) { int32 i; + // Dereference t so that any panic happens before the lock is held. + // Discard result, because t might be moving in the heap. + i = t->i; + USED(i); + runtime·lock(&timers); // t may not be registered anymore and may have diff --git a/src/pkg/time/sleep_test.go b/src/pkg/time/sleep_test.go index 1322f06114..603adc9b89 100644 --- a/src/pkg/time/sleep_test.go +++ b/src/pkg/time/sleep_test.go @@ -314,3 +314,23 @@ func TestOverflowSleep(t *testing.T) { t.Fatalf("negative timeout didn't fire") } } + +// Test that a panic while deleting a timer does not leave +// the timers mutex held, deadlocking a ticker.Stop in a defer. +func TestIssue5745(t *testing.T) { + ticker := NewTicker(Hour) + defer func() { + // would deadlock here before the fix due to + // lock taken before the segfault. + ticker.Stop() + + if r := recover(); r == nil { + t.Error("Expected panic, but none happened.") + } + }() + + // cause a panic due to a segfault + var timer *Timer + timer.Stop() + t.Error("Should be unreachable.") +} |