filestar-project/lotus: extern/storage-sealing/fsm.go; 36 LoC

Found a possible issue in [filestar-project/lotus](https://www.github.com/filestar-project/lotus) at [extern/storage-sealing/fsm.go](https://github.com/filestar-project/lotus/blob/b3223e189d08b89aea15297e3dc582b65a1a190d/extern/storage-sealing/fsm.go#L387-L422)

Below is the message reported by the analyzer for this snippet of code. Beware that the analyzer only reports the first
issue it finds, so please do not limit your consideration to the contents of the below message.

> range-loop variable sector used in defer or goroutine at line 416

[Click here to see the code in its original context.](https://github.com/filestar-project/lotus/blob/b3223e189d08b89aea15297e3dc582b65a1a190d/extern/storage-sealing/fsm.go#L387-L422)

Click here to show the 36 line(s) of Go which triggered the analyzer.

```go
for _, sector := range trackedSectors {
if err := m.sectors.Send(uint64(sector.SectorNumber), SectorRestart{}); err != nil {
log.Errorf("restarting sector %d: %+v", sector.SectorNumber, err)
}

if sector.State == WaitDeals {

// put the sector in the unsealedInfoMap
if _, ok := m.unsealedInfoMap.infos[sector.SectorNumber]; ok {
// something's funky here, but probably safe to move on
log.Warnf("sector %v was already in the unsealedInfoMap when restarting", sector.SectorNumber)
} else {
ui := UnsealedSectorInfo{}
for _, p := range sector.Pieces {
if p.DealInfo != nil {
ui.numDeals++
}
ui.stored += p.Piece.Size
ui.pieceSizes = append(ui.pieceSizes, p.Piece.Size.Unpadded())
}

m.unsealedInfoMap.infos[sector.SectorNumber] = ui
}

// start a fresh timer for the sector
if cfg.WaitDealsDelay > 0 {
timer := time.NewTimer(cfg.WaitDealsDelay)
go func() {
<-timer.C
if err := m.StartPacking(sector.SectorNumber); err != nil {
log.Errorf("starting sector %d: %+v", sector.SectorNumber, err)
}
}()
}
}
}

```

Leave a reaction on this issue to contribute to the project by classifying this instance as a **Bug** :-1:, **Mitigated** :+1:, or **Desirable Behavior** :rocket:
See the descriptions of the classifications [here](https://github.com/github-vet/rangeclosure-findings#how-can-i-help) for more information.

commit ID: b3223e189d08b89aea15297e3dc582b65a1a190d