From a7b58b8eb3f07b8d0a0612a53839fbc3b3a0a82a Mon Sep 17 00:00:00 2001
From: Lei Xue <vfs@live.com>
Date: Tue, 17 Mar 2026 15:01:22 +0800
Subject: [PATCH] fix: handle discovery sessions in UnBindISCSISession

Discovery sessions have nil Target and nil ITNexus. The cleanup
path crashed with nil pointer dereference when trying to remove
ITNexus or access Target.Sessions for discovery sessions.

Guard against nil Target (just release TSIH) and nil ITNexus.
Also add nil safety to clearHostIP helper.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 pkg/port/iscsit/iscsid.go  | 11 +++++++++--
 pkg/port/iscsit/session.go |  9 ++++++++-
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/pkg/port/iscsit/iscsid.go b/pkg/port/iscsit/iscsid.go
index c65e444..2022674 100644
--- a/pkg/port/iscsit/iscsid.go
+++ b/pkg/port/iscsit/iscsid.go
@@ -376,12 +376,19 @@ func (s *ISCSITargetDriver) handler(events byte, conn *iscsiConnection) {
 }
 
 func (s *ISCSITargetDriver) clearHostIP(conn *iscsiConnection) {
+	if conn.conn == nil {
+		return
+	}
 	IPMutex.Lock()
-	remoteIP := strings.Split(conn.conn.RemoteAddr().String(), ":")[0]
+	defer IPMutex.Unlock()
+	addr := conn.conn.RemoteAddr()
+	if addr == nil {
+		return
+	}
+	remoteIP := strings.Split(addr.String(), ":")[0]
 	if CurrentHostIP == remoteIP {
 		CurrentHostIP = ""
 	}
-	IPMutex.Unlock()
 }
 
 func (s *ISCSITargetDriver) rxHandler(conn *iscsiConnection) {
diff --git a/pkg/port/iscsit/session.go b/pkg/port/iscsit/session.go
index d3bb8ea..b6c8aa3 100644
--- a/pkg/port/iscsit/session.go
+++ b/pkg/port/iscsit/session.go
@@ -330,10 +330,17 @@ func (s *ISCSITargetDriver) LookupISCSISession(tgtName string, iniName string, i
 
 func (s *ISCSITargetDriver) UnBindISCSISession(sess *ISCSISession) {
 	target := sess.Target
+	if target == nil {
+		// Discovery sessions have no target; just release the TSIH.
+		s.ReleaseTSIH(sess.TSIH)
+		return
+	}
 	target.SessionsRWMutex.Lock()
 	defer target.SessionsRWMutex.Unlock()
 	delete(target.Sessions, sess.TSIH)
-	scsi.RemoveITNexus(sess.Target.SCSITarget, sess.ITNexus)
+	if sess.ITNexus != nil {
+		scsi.RemoveITNexus(target.SCSITarget, sess.ITNexus)
+	}
 	s.ReleaseTSIH(sess.TSIH)
 	log.Infof("session %x unbound from target %s", sess.TSIH, target.SCSITarget.Name)
 }