Fix concurrent map read/write, maybe

network/clean.go

@@ -41,8 +41,14 @@ func cleanConnections() (activePIDs map[int]struct{}) {
 		now := time.Now().Unix()
 		deleteOlderThan := time.Now().Add(-deleteConnsAfterEndedThreshold).Unix()
 
-		// network connections
+		// lock both together because we cannot fully guarantee in which map a connection lands
+		// of course every connection should land in the correct map, but this increases resilience
 		connsLock.Lock()
+		defer connsLock.Unlock()
+		dnsConnsLock.Lock()
+		defer dnsConnsLock.Unlock()
+
+		// network connections
 		for key, conn := range conns {
 			conn.Lock()
 
@@ -67,10 +73,8 @@ func cleanConnections() (activePIDs map[int]struct{}) {
 
 			conn.Unlock()
 		}
-		connsLock.Unlock()
 
 		// dns requests
-		dnsConnsLock.Lock()
 		for _, conn := range dnsConns {
 			conn.Lock()
 
@@ -82,7 +86,6 @@ func cleanConnections() (activePIDs map[int]struct{}) {
 
 			conn.Unlock()
 		}
-		dnsConnsLock.Unlock()
 
 		return nil
 	})

network/database.go

@@ -77,9 +77,11 @@ func (s *StorageInterface) processQuery(q *query.Query, it *iterator.Iterator) {
 	if slashes <= 1 {
 		// processes
 		for _, proc := range process.All() {
+			proc.Lock()
 			if q.Matches(proc) {
 				it.Next <- proc
 			}
+			proc.Unlock()
 		}
 	}
 
@@ -87,9 +89,11 @@ func (s *StorageInterface) processQuery(q *query.Query, it *iterator.Iterator) {
 		// dns scopes only
 		dnsConnsLock.RLock()
 		for _, dnsConn := range dnsConns {
+			dnsConn.Lock()
 			if q.Matches(dnsConn) {
 				it.Next <- dnsConn
 			}
+			dnsConn.Unlock()
 		}
 		dnsConnsLock.RUnlock()
 	}
@@ -98,9 +102,11 @@ func (s *StorageInterface) processQuery(q *query.Query, it *iterator.Iterator) {
 		// connections
 		connsLock.RLock()
 		for _, conn := range conns {
+			conn.Lock()
 			if q.Matches(conn) {
 				it.Next <- conn
 			}
+			conn.Unlock()
 		}
 		connsLock.RUnlock()
 	}