net/dns: update to illarion/gonotify/v3 to fix a panic

Fixes tailscale#14699

Signed-off-by: Anton <anton@tailscale.com>

Author: knyar

cmd/k8s-operator/depaware.txt

@@ -142,7 +142,8 @@ tailscale.com/cmd/k8s-operator dependencies: (generated by github.com/tailscale/
         github.com/gorilla/csrf                                      from tailscale.com/client/web
         github.com/gorilla/securecookie                              from github.com/gorilla/csrf
         github.com/hdevalence/ed25519consensus                       from tailscale.com/clientupdate/distsign+
-   L 💣 github.com/illarion/gonotify/v2                              from tailscale.com/net/dns
+   L 💣 github.com/illarion/gonotify/v3                              from tailscale.com/net/dns
+   L    github.com/illarion/gonotify/v3/syscallf                     from github.com/illarion/gonotify/v3
    L    github.com/insomniacslk/dhcp/dhcpv4                          from tailscale.com/feature/tap
    L    github.com/insomniacslk/dhcp/iana                            from github.com/insomniacslk/dhcp/dhcpv4
    L    github.com/insomniacslk/dhcp/interfaces                      from github.com/insomniacslk/dhcp/dhcpv4

cmd/tailscaled/depaware.txt

@@ -114,7 +114,8 @@ tailscale.com/cmd/tailscaled dependencies: (generated by github.com/tailscale/de
         github.com/gorilla/csrf                                      from tailscale.com/client/web
         github.com/gorilla/securecookie                              from github.com/gorilla/csrf
         github.com/hdevalence/ed25519consensus                       from tailscale.com/clientupdate/distsign+
-   L 💣 github.com/illarion/gonotify/v2                              from tailscale.com/net/dns
+   L 💣 github.com/illarion/gonotify/v3                              from tailscale.com/net/dns
+   L    github.com/illarion/gonotify/v3/syscallf                     from github.com/illarion/gonotify/v3
    L    github.com/insomniacslk/dhcp/dhcpv4                          from tailscale.com/feature/tap
    L    github.com/insomniacslk/dhcp/iana                            from github.com/insomniacslk/dhcp/dhcpv4
    L    github.com/insomniacslk/dhcp/interfaces                      from github.com/insomniacslk/dhcp/dhcpv4

go.mod

@@ -48,7 +48,7 @@ require (
 	github.com/google/uuid v1.6.0
 	github.com/goreleaser/nfpm/v2 v2.33.1
 	github.com/hdevalence/ed25519consensus v0.2.0
-	github.com/illarion/gonotify/v2 v2.0.3
+	github.com/illarion/gonotify/v3 v3.0.2
 	github.com/inetaf/tcpproxy v0.0.0-20250203165043-ded522cbd03f
 	github.com/insomniacslk/dhcp v0.0.0-20231206064809-8c70d406f6d2
 	github.com/jellydator/ttlcache/v3 v3.1.0

go.sum

@@ -554,8 +554,8 @@ github.com/huandu/xstrings v1.5.0/go.mod h1:y5/lhBue+AyNmUVz9RLU9xbLR0o4KIIExikq
 github.com/hugelgupf/vmtest v0.0.0-20240102225328-693afabdd27f h1:ov45/OzrJG8EKbGjn7jJZQJTN7Z1t73sFYNIRd64YlI=
 github.com/hugelgupf/vmtest v0.0.0-20240102225328-693afabdd27f/go.mod h1:JoDrYMZpDPYo6uH9/f6Peqms3zNNWT2XiGgioMOIGuI=
 github.com/ianlancetaylor/demangle v0.0.0-20181102032728-5e5cf60278f6/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
-github.com/illarion/gonotify/v2 v2.0.3 h1:B6+SKPo/0Sw8cRJh1aLzNEeNVFfzE3c6N+o+vyxM+9A=
-github.com/illarion/gonotify/v2 v2.0.3/go.mod h1:38oIJTgFqupkEydkkClkbL6i5lXV/bxdH9do5TALPEE=
+github.com/illarion/gonotify/v3 v3.0.2 h1:O7S6vcopHexutmpObkeWsnzMJt/r1hONIEogeVNmJMk=
+github.com/illarion/gonotify/v3 v3.0.2/go.mod h1:HWGPdPe817GfvY3w7cx6zkbzNZfi3QjcBm/wgVvEL1U=
 github.com/imdario/mergo v0.3.11/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
 github.com/imdario/mergo v0.3.16 h1:wwQJbIsHYGMUyLSPrEq1CT16AhnhNJQ51+4fdHUnCl4=
 github.com/imdario/mergo v0.3.16/go.mod h1:WBLT9ZmE3lPoWsEzCh9LPo3TiwVN+ZKEjmz+hD27ysY=

net/dns/direct_linux.go

@@ -8,7 +8,7 @@ import (
 	"context"
 	"fmt"
 
-	"github.com/illarion/gonotify/v2"
+	"github.com/illarion/gonotify/v3"
 	"tailscale.com/health"
 )
 
@@ -25,10 +25,6 @@ func (m *directManager) runFileWatcher() {
 func watchFile(ctx context.Context, dir, filename string, cb func()) error {
 	ctx, cancel := context.WithCancel(ctx)
 	defer cancel()
-	in, err := gonotify.NewInotify(ctx)
-	if err != nil {
-		return fmt.Errorf("NewInotify: %w", err)
-	}
 
 	const events = gonotify.IN_ATTRIB |
 		gonotify.IN_CLOSE_WRITE |
@@ -37,28 +33,20 @@ func watchFile(ctx context.Context, dir, filename string, cb func()) error {
 		gonotify.IN_MODIFY |
 		gonotify.IN_MOVE
 
-	if err := in.AddWatch(dir, events); err != nil {
-		return fmt.Errorf("AddWatch: %w", err)
+	watcher, err := gonotify.NewDirWatcher(ctx, events, dir)
+	if err != nil {
+		return fmt.Errorf("NewDirWatcher: %w", err)
 	}
+
 	for {
-		events, err := in.Read()
-		if ctx.Err() != nil {
-			return ctx.Err()
-		}
-		if err != nil {
-			return fmt.Errorf("Read: %w", err)
-		}
-		var match bool
-		for _, ev := range events {
-			if ev.Name == filename {
-				match = true
-				break
+		select {
+		case event := <-watcher.C:
+			if event.Name == filename {
+				cb()
 			}
+		case <-ctx.Done():
+			return ctx.Err()
 		}
-		if !match {
-			continue
-		}
-		cb()
 	}
 }