light: correctly handle contexts (backport -> v0.34.x) (#6685)

statesync/reactor.go

@@ -154,6 +154,7 @@ func (r *Reactor) Receive(chID byte, src p2p.Peer, msgBytes []byte) {
 				Hash:     msg.Hash,
 				Metadata: msg.Metadata,
 			})
+			// TODO: We may want to consider punishing the peer for certain errors
 			if err != nil {
 				r.Logger.Error("Failed to add snapshot", "height", msg.Height, "format", msg.Format,
 					"peer", src.ID(), "err", err)

statesync/syncer.go

@@ -213,6 +213,10 @@ func (s *syncer) SyncAny(discoveryTime time.Duration, retryHook func()) (sm.Stat
 				s.logger.Info("Snapshot sender rejected", "peer", peer.ID())
 			}
 
+		case errors.Is(err, context.DeadlineExceeded):
+			s.logger.Info("Timed out validating snapshot, rejecting", "height", snapshot.Height, "err", err)
+			s.snapshots.Reject(snapshot)
+
 		default:
 			return sm.State{}, nil, fmt.Errorf("snapshot restoration failed: %w", err)
 		}
@@ -256,7 +260,7 @@ func (s *syncer) Sync(snapshot *snapshot, chunks *chunkQueue) (sm.State, *types.
 		go s.fetchChunks(ctx, snapshot, chunks)
 	}
 
-	pctx, pcancel := context.WithTimeout(context.Background(), 10*time.Second)
+	pctx, pcancel := context.WithTimeout(context.Background(), 15*time.Second)
 	defer pcancel()
 
 	// Optimistically build new state, so we don't discover any light client failures at the end.