fix deadlocks

internal/timesync/ntp.go

@@ -3,6 +3,7 @@ package timesync
 import (
 	"context"
 	"math/rand/v2"
+	"net"
 	"strconv"
 	"time"
 
@@ -37,7 +38,47 @@ var DefaultNTPServerHostnames = []string{
 	"pool.ntp.org",
 }
 
+func (t *TimeSync) filterNTPServers(ntpServers []string) ([]string, error) {
+	if len(ntpServers) == 0 {
+		return nil, nil
+	}
+
+	hasIPv4, err := t.preCheckIPv4()
+	if err != nil {
+		t.l.Error().Err(err).Msg("failed to check IPv4")
+		return nil, err
+	}
+
+	hasIPv6, err := t.preCheckIPv6()
+	if err != nil {
+		t.l.Error().Err(err).Msg("failed to check IPv6")
+		return nil, err
+	}
+
+	filteredServers := []string{}
+	for _, server := range ntpServers {
+		ip := net.ParseIP(server)
+		t.l.Trace().Str("server", server).Interface("ip", ip).Msg("checking NTP server")
+		if ip == nil {
+			continue
+		}
+		if hasIPv4 && ip.To4() != nil {
+			filteredServers = append(filteredServers, server)
+		}
+		if hasIPv6 && ip.To16() != nil {
+			filteredServers = append(filteredServers, server)
+		}
+	}
+	return filteredServers, nil
+}
+
 func (t *TimeSync) queryNetworkTime(ntpServers []string) (now *time.Time, offset *time.Duration) {
+	ntpServers, err := t.filterNTPServers(ntpServers)
+	if err != nil {
+		t.l.Error().Err(err).Msg("failed to filter NTP servers")
+		return nil, nil
+	}
+
 	chunkSize := int(t.networkConfig.TimeSyncParallel.ValueOr(4))
 	t.l.Info().Strs("servers", ntpServers).Int("chunkSize", chunkSize).Msg("querying NTP servers")
 

internal/timesync/timesync.go

@@ -24,6 +24,8 @@ var (
 	timeSyncRetryInterval = 0 * time.Second
 )
 
+type PreCheckFunc func() (bool, error)
+
 type TimeSync struct {
 	syncLock *sync.Mutex
 	l        *zerolog.Logger
@@ -37,11 +39,15 @@ type TimeSync struct {
 
 	syncSuccess bool
 
-	preCheckFunc func() (bool, error)
+	preCheckFunc PreCheckFunc
+	preCheckIPv4 PreCheckFunc
+	preCheckIPv6 PreCheckFunc
 }
 
 type TimeSyncOptions struct {
-	PreCheckFunc  func() (bool, error)
+	PreCheckFunc  PreCheckFunc
+	PreCheckIPv4  PreCheckFunc
+	PreCheckIPv6  PreCheckFunc
 	Logger        *zerolog.Logger
 	NetworkConfig *types.NetworkConfig
 }
@@ -69,6 +75,8 @@ func NewTimeSync(opts *TimeSyncOptions) *TimeSync {
 		rtcDevicePath:    rtcDevice,
 		rtcLock:          &sync.Mutex{},
 		preCheckFunc:     opts.PreCheckFunc,
+		preCheckIPv4:     opts.PreCheckIPv4,
+		preCheckIPv6:     opts.PreCheckIPv6,
 		networkConfig:    opts.NetworkConfig,
 	}
 
@@ -112,7 +120,13 @@ func (t *TimeSync) getSyncMode() SyncMode {
 		}
 	}
 
-	t.l.Debug().Strs("Ordering", syncMode.Ordering).Bool("Ntp", syncMode.Ntp).Bool("Http", syncMode.Http).Bool("NtpUseFallback", syncMode.NtpUseFallback).Bool("HttpUseFallback", syncMode.HttpUseFallback).Msg("sync mode")
+	t.l.Debug().
+		Strs("Ordering", syncMode.Ordering).
+		Bool("Ntp", syncMode.Ntp).
+		Bool("Http", syncMode.Http).
+		Bool("NtpUseFallback", syncMode.NtpUseFallback).
+		Bool("HttpUseFallback", syncMode.HttpUseFallback).
+		Msg("sync mode")
 
 	return syncMode
 }

pkg/nmlite/interface.go

@@ -152,30 +152,63 @@ func (im *InterfaceManager) link() (*link.Link, error) {
 
 // IsUp returns true if the interface is up
 func (im *InterfaceManager) IsUp() bool {
+	im.stateMu.RLock()
+	defer im.stateMu.RUnlock()
+
 	return im.state.Up
 }
 
 func (im *InterfaceManager) IsOnline() bool {
-	return im.IsUp()
+	im.stateMu.RLock()
+	defer im.stateMu.RUnlock()
+
+	return im.state.Online
+}
+
+func (im *InterfaceManager) IPv4Ready() bool {
+	im.stateMu.RLock()
+	defer im.stateMu.RUnlock()
+
+	return im.state.IPv4Ready
+}
+
+func (im *InterfaceManager) IPv6Ready() bool {
+	im.stateMu.RLock()
+	defer im.stateMu.RUnlock()
+
+	return im.state.IPv6Ready
 }
 
 func (im *InterfaceManager) GetIPv4Addresses() []string {
+	im.stateMu.RLock()
+	defer im.stateMu.RUnlock()
+
 	return im.state.IPv4Addresses
 }
 
 func (im *InterfaceManager) GetIPv4Address() string {
+	im.stateMu.RLock()
+	defer im.stateMu.RUnlock()
+
 	return im.state.IPv4Address
 }
 
 func (im *InterfaceManager) GetIPv6Address() string {
+	im.stateMu.RLock()
+	defer im.stateMu.RUnlock()
+
 	return im.state.IPv6Address
 }
 
 func (im *InterfaceManager) GetIPv6Addresses() []string {
+	im.stateMu.RLock()
+	defer im.stateMu.RUnlock()
+
 	addresses := []string{}
 	for _, addr := range im.state.IPv6Addresses {
 		addresses = append(addresses, addr.Address.String())
 	}
+
 	return []string{}
 }
 
@@ -569,11 +602,11 @@ func (im *InterfaceManager) updateInterfaceState() error {
 		hasAddrs = true
 	}
 
-	im.stateMu.Lock()
-	defer im.stateMu.Unlock()
-
 	// Check if state changed
 	stateChanged := false
+	// We should release the lock before calling the callbacks
+	// to avoid deadlocks
+	im.stateMu.Lock()
 	if im.state.Up != isUp {
 		im.state.Up = isUp
 		stateChanged = true
@@ -594,6 +627,7 @@ func (im *InterfaceManager) updateInterfaceState() error {
 	}
 
 	im.state.LastUpdated = time.Now()
+	im.stateMu.Unlock()
 
 	// Notify callback if state changed
 	if stateChanged && im.onStateChange != nil {
@@ -661,9 +695,8 @@ func (im *InterfaceManager) updateIPAddresses(nl *link.Link) error {
 // updateStateFromDHCPLease updates the state from a DHCP lease
 func (im *InterfaceManager) updateStateFromDHCPLease(lease *types.DHCPLease) {
 	im.stateMu.Lock()
-	defer im.stateMu.Unlock()
-
 	im.state.DHCPLease4 = lease
+	im.stateMu.Unlock()
 
 	// Update resolv.conf with DNS information
 	if im.resolvConf != nil {

pkg/nmlite/state.go

@@ -12,7 +12,12 @@ func (nm *NetworkManager) IsOnline() bool {
 }
 
 func (nm *NetworkManager) IsUp() bool {
-	return nm.IsOnline()
+	for _, iface := range nm.interfaces {
+		if iface.IsUp() {
+			return true
+		}
+	}
+	return false
 }
 
 func (nm *NetworkManager) GetHostname() string {
@@ -74,6 +79,20 @@ func (nm *NetworkManager) GetMACAddress() string {
 	return ""
 }
 
+func (nm *NetworkManager) IPv4Ready() bool {
+	for _, iface := range nm.interfaces {
+		return iface.IPv4Ready()
+	}
+	return false
+}
+
+func (nm *NetworkManager) IPv6Ready() bool {
+	for _, iface := range nm.interfaces {
+		return iface.IPv6Ready()
+	}
+	return false
+}
+
 func (nm *NetworkManager) IPv4String() string {
 	return nm.GetIPv4Address()
 }

timesync.go

@@ -43,6 +43,18 @@ func initTimeSync() {
 	timeSync = timesync.NewTimeSync(&timesync.TimeSyncOptions{
 		Logger:        timesyncLogger,
 		NetworkConfig: config.NetworkConfig,
+		PreCheckIPv4: func() (bool, error) {
+			if !networkManager.IPv4Ready() {
+				return false, nil
+			}
+			return true, nil
+		},
+		PreCheckIPv6: func() (bool, error) {
+			if !networkManager.IPv6Ready() {
+				return false, nil
+			}
+			return true, nil
+		},
 		PreCheckFunc: func() (bool, error) {
 			if !networkManager.IsOnline() {
 				return false, nil