From 6f92672308e9ff2ff72f1d929b6887ab24787e42 Mon Sep 17 00:00:00 2001
From: Harlen Stenn <stenn@ntp.org>
Date: Tue, 20 Jun 2023 18:41:55 +0000
Subject: [PATCH] add NULL pointer check when ntpd deletes the last interface

Conflict:NA
Reference:https://bugs.ntp.org/attachment.cgi?id=1854&action=diff

---
 include/ntp_lists.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/ntp_lists.h b/include/ntp_lists.h
index d741974..37befc0 100644
--- a/include/ntp_lists.h
+++ b/include/ntp_lists.h
@@ -181,7 +181,7 @@ do {								\
 
 #define UNLINK_EXPR_SLIST(punlinked, listhead, expr, nextlink,	\
 			  entrytype)				\
-do {								\
+if (NULL != (listhead)) {						\
 	entrytype **ppentry;					\
 								\
 	ppentry = &(listhead);					\
@@ -202,6 +202,8 @@ do {								\
 	} else {						\
 		(punlinked) = NULL;				\
 	}							\
+} else do {                     \
+    (punlinked) = NULL;                 \
 } while (FALSE)
 
 #define UNLINK_SLIST(punlinked, listhead, ptounlink, nextlink,	\
-- 
2.27.0