Merge pull request #7188 from guggero/go-func-vars

Don't access loop variables in goroutines directly

chainntnfs/bitcoindnotify/bitcoind.go

@@ -235,7 +235,9 @@ out:
 				//
 				// TODO(wilmer): add retry logic if rescan fails?
 				b.wg.Add(1)
-				go func() {
+
+				//nolint:lll
+				go func(msg *chainntnfs.HistoricalConfDispatch) {
 					defer b.wg.Done()
 
 					confDetails, _, err := b.historicalConfDetails(
@@ -269,7 +271,7 @@ out:
 							"details of %v: %v",
 							msg.ConfRequest, err)
 					}
-				}()
+				}(msg)
 
 			case *chainntnfs.HistoricalSpendDispatch:
 				// In order to ensure we don't block the caller
@@ -278,7 +280,9 @@ out:
 				//
 				// TODO(wilmer): add retry logic if rescan fails?
 				b.wg.Add(1)
-				go func() {
+
+				//nolint:lll
+				go func(msg *chainntnfs.HistoricalSpendDispatch) {
 					defer b.wg.Done()
 
 					spendDetails, err := b.historicalSpendDetails(
@@ -320,7 +324,7 @@ out:
 							"details of %v: %v",
 							msg.SpendRequest, err)
 					}
-				}()
+				}(msg)
 
 			case *blockEpochRegistration:
 				chainntnfs.Log.Infof("New block epoch subscription")

chainntnfs/btcdnotify/btcd.go

@@ -347,7 +347,9 @@ out:
 				//
 				// TODO(wilmer): add retry logic if rescan fails?
 				b.wg.Add(1)
-				go func() {
+
+				//nolint:lll
+				go func(msg *chainntnfs.HistoricalConfDispatch) {
 					defer b.wg.Done()
 
 					confDetails, _, err := b.historicalConfDetails(
@@ -372,7 +374,7 @@ out:
 					if err != nil {
 						chainntnfs.Log.Error(err)
 					}
-				}()
+				}(msg)
 
 			case *blockEpochRegistration:
 				chainntnfs.Log.Infof("New block epoch subscription")

chainntnfs/neutrinonotify/neutrino.go

@@ -432,7 +432,9 @@ func (n *NeutrinoNotifier) notificationDispatcher() {
 				// chain asynchronously to prevent blocking
 				// potentially long rescans.
 				n.wg.Add(1)
-				go func() {
+
+				//nolint:lll
+				go func(msg *chainntnfs.HistoricalConfDispatch) {
 					defer n.wg.Done()
 
 					confDetails, err := n.historicalConfDetails(
@@ -457,7 +459,7 @@ func (n *NeutrinoNotifier) notificationDispatcher() {
 					if err != nil {
 						chainntnfs.Log.Error(err)
 					}
-				}()
+				}(msg)
 
 			case *blockEpochRegistration:
 				chainntnfs.Log.Infof("New block epoch subscription")

discovery/gossiper.go

@@ -1325,6 +1325,7 @@ func (d *AuthenticatedGossiper) networkHandler() {
 			d.wg.Add(1)
 			go func() {
 				defer d.wg.Done()
+
 				log.Infof("Broadcasting %v new announcements in %d sub batches",
 					len(announcementBatch), len(splitAnnouncementBatch))
 
@@ -2947,6 +2948,7 @@ func (d *AuthenticatedGossiper) handleAnnSig(nMsg *networkMsg,
 			d.wg.Add(1)
 			go func() {
 				defer d.wg.Done()
+
 				log.Debugf("Received half proof for channel "+
 					"%v with existing full proof. Sending"+
 					" full proof to peer=%x",

docs/release-notes/release-notes-0.16.0.md

@@ -198,6 +198,9 @@ certain large transactions](https://github.com/lightningnetwork/lnd/pull/7100).
 
 * [test: fix loop variables being accessed in
   closures](https://github.com/lightningnetwork/lnd/pull/7032).
+
+* [Fix loop and other temporary variables being accessed in
+  goroutines](https://github.com/lightningnetwork/lnd/pull/7188).
  
 ## Watchtowers
 

funding/manager.go

@@ -1969,6 +1969,7 @@ func (f *Manager) handleFundingAccept(peer lnpeer.Peer,
 		f.wg.Add(1)
 		go func() {
 			defer f.wg.Done()
+
 			f.waitForPsbt(psbtIntent, resCtx, pendingChanID)
 		}()
 

healthcheck/healthcheck.go

@@ -71,10 +71,11 @@ func (m *Monitor) Start() error {
 		}
 
 		m.wg.Add(1)
-		go func() {
+		go func(check *Observation) {
 			defer m.wg.Done()
+
 			check.monitor(m.cfg.Shutdown, m.quit)
-		}()
+		}(check)
 	}
 
 	return nil

htlcswitch/switch.go

@@ -1742,6 +1742,7 @@ func (s *Switch) htlcForwarder() {
 			wg.Add(1)
 			go func(l ChannelLink) {
 				defer wg.Done()
+
 				l.Stop()
 			}(link)
 		}

lntest/itest/utils.go

@@ -78,13 +78,12 @@ func completePaymentRequests(client lnrpc.LightningClient,
 	// Launch all payments simultaneously.
 	results := make(chan error)
 	for _, payReq := range paymentRequests {
-		payReqCopy := payReq
+		go func(payReq string) {
-		go func() {
+			err := send(payReq)
-			err := send(payReqCopy)
 			if awaitResponse {
 				results <- err
 			}
-		}()
+		}(payReq)
 	}
 
 	// If awaiting a response, verify that all payments succeeded.
@@ -406,6 +405,7 @@ func subscribeChannelNotifications(ctxb context.Context, t *harnessTest,
 	chanUpdates := make(chan *lnrpc.ChannelEventUpdate, 20)
 	go func() {
 		defer cancelFunc()
+
 		for {
 			select {
 			case <-quit:

lnwallet/btcwallet/btcwallet.go

@@ -1483,9 +1483,13 @@ out:
 
 			// Launch a goroutine to re-package and send
 			// notifications for any newly confirmed transactions.
-			go func() {
+			//nolint:lll
+			go func(txNtfn *wallet.TransactionNotifications) {
 				for _, block := range txNtfn.AttachedBlocks {
-					details, err := minedTransactionsToDetails(currentHeight, block, t.w.ChainParams())
+					details, err := minedTransactionsToDetails(
+						currentHeight, block,
+						t.w.ChainParams(),
+					)
 					if err != nil {
 						continue
 					}
@@ -1499,11 +1503,11 @@ out:
 					}
 				}
 
-			}()
+			}(txNtfn)
 
 			// Launch a goroutine to re-package and send
 			// notifications for any newly unconfirmed transactions.
-			go func() {
+			go func(txNtfn *wallet.TransactionNotifications) {
 				for _, tx := range txNtfn.UnminedTransactions {
 					detail, err := unminedTransactionsToDetail(
 						tx, t.w.ChainParams(),
@@ -1518,7 +1522,7 @@ out:
 						return
 					}
 				}
-			}()
+			}(txNtfn)
 		case <-t.quit:
 			break out
 		}

rpcperms/middleware_handler.go

@@ -180,8 +180,9 @@ func (h *MiddlewareHandler) Run() error {
 	// request to the client).
 	h.wg.Add(1)
 	go func() {
+		defer h.wg.Done()
+
 		h.receiveResponses(errChan, responses)
-		h.wg.Done()
 	}()
 
 	return h.sendInterceptRequests(errChan, responses)

rpcserver.go

@@ -5214,7 +5214,7 @@ sendLoop:
 			// payment so we can continue to serve requests while
 			// this payment is being dispatched.
 			wg.Add(1)
-			go func() {
+			go func(payIntent *rpcPaymentIntent) {
 				defer wg.Done()
 
 				// Attempt to grab a free semaphore slot, using
@@ -5292,7 +5292,7 @@ sendLoop:
 					}
 					return
 				}
-			}()
+			}(payIntent)
 		}
 	}
 

sweep/sweeper.go

@@ -1415,6 +1415,7 @@ func (s *UtxoSweeper) waitForSpend(outpoint wire.OutPoint,
 	s.wg.Add(1)
 	go func() {
 		defer s.wg.Done()
+
 		select {
 		case spend, ok := <-spendEvent.Spend:
 			if !ok {

ticker/force.go

@@ -39,6 +39,7 @@ func NewForce(interval time.Duration) *Force {
 	m.wg.Add(1)
 	go func() {
 		defer m.wg.Done()
+
 		for {
 			select {
 			case t := <-m.ticker:

watchtower/wtclient/session_queue.go

@@ -689,6 +689,7 @@ func (s *sessionQueueSet) ApplyAndWait(getApply func(*sessionQueue) func()) {
 		wg.Add(1)
 		go func(sq *sessionQueue) {
 			defer wg.Done()
+
 			getApply(sq)()
 		}(sessionq)
 	}