From 4537a1ac0023a5fc7816dc64915c67ad5253b6c1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E4=B8=96=E7=95=8C?= <i@sekai.icu>
Date: Fri, 25 Sep 2026 19:28:45 +0800
Subject: [PATCH] Fix system TUN read loop stopping on write errors

---
 transport/openconnect/device_system.go | 9 +++------
 transport/openvpn/device_system.go     | 9 +++------
 2 files changed, 6 insertions(+), 12 deletions(-)

diff --git a/transport/openconnect/device_system.go b/transport/openconnect/device_system.go
index 0750dc73..ac96666c 100644
--- a/transport/openconnect/device_system.go
+++ b/transport/openconnect/device_system.go
@@ -152,8 +152,7 @@ func (d *systemDevice) readLoop(tunInterface tun.Tun, mtu int) {
 		err = d.writeOutbound([]*buf.Buffer{packetBuffer})
 		packetBuffer.DecRef()
 		if err != nil {
-			d.options.Logger.Error(E.Cause(err, "write packet"))
-			return
+			d.options.Logger.Debug(E.Cause(err, "write packet"))
 		}
 	}
 }
@@ -183,8 +182,7 @@ func (d *systemDevice) readLoopLinux(tunInterface tun.LinuxTUN, batchSize int, m
 				packetBuffers[i].DecRef()
 			}
 			if writeErr != nil {
-				d.options.Logger.Error(E.Cause(writeErr, "write packet batch"))
-				return
+				d.options.Logger.Debug(E.Cause(writeErr, "write packet batch"))
 			}
 		}
 		if readErr != nil {
@@ -211,8 +209,7 @@ func (d *systemDevice) readLoopDarwin(tunInterface tun.DarwinTUN) {
 		if len(outboundBuffers) > 0 {
 			writeErr := d.writeOutbound(outboundBuffers)
 			if writeErr != nil {
-				d.options.Logger.Error(E.Cause(writeErr, "write packet batch"))
-				return
+				d.options.Logger.Debug(E.Cause(writeErr, "write packet batch"))
 			}
 		}
 		if readErr != nil {
diff --git a/transport/openvpn/device_system.go b/transport/openvpn/device_system.go
index 728626a9..ed393e30 100644
--- a/transport/openvpn/device_system.go
+++ b/transport/openvpn/device_system.go
@@ -155,8 +155,7 @@ func (d *systemDevice) readLoop(tunInterface tun.Tun, mtu int) {
 		err = d.writeOutbound([]*buf.Buffer{packetBuffer})
 		packetBuffer.DecRef()
 		if err != nil {
-			d.options.Logger.Error(E.Cause(err, "write packet"))
-			return
+			d.options.Logger.Debug(E.Cause(err, "write packet"))
 		}
 	}
 }
@@ -193,8 +192,7 @@ func (d *systemDevice) readLoopLinux(tunInterface tun.LinuxTUN, batchSize int, m
 				packetBuffer.DecRef()
 			}
 			if writeErr != nil {
-				d.options.Logger.Error(E.Cause(writeErr, "write packet batch"))
-				return
+				d.options.Logger.Debug(E.Cause(writeErr, "write packet batch"))
 			}
 		}
 		if readErr != nil {
@@ -226,8 +224,7 @@ func (d *systemDevice) readLoopDarwin(tunInterface tun.DarwinTUN) {
 		if len(outboundBuffers) > 0 {
 			writeErr := d.writeOutbound(outboundBuffers)
 			if writeErr != nil {
-				d.options.Logger.Error(E.Cause(writeErr, "write packet batch"))
-				return
+				d.options.Logger.Debug(E.Cause(writeErr, "write packet batch"))
 			}
 		}
 		if readErr != nil {