From 0a9a570d9b84f5974b7fbb45e63cdecc131cfdd4 Mon Sep 17 00:00:00 2001
From: JHB11Hinson <lemonoutput@foxmail.com>
Date: Thu, 24 Sep 2026 21:24:52 +0800
Subject: [PATCH] [net][lwip-dhcpd] Add missing <string.h> include in
 dhcp_server_raw.c

dhcp_server_raw.c calls memcmp(), memset(), strlen(), strncmp() and
strchr() without including <string.h>. They are then implicitly declared
as returning int, which is undefined behaviour and, on 64-bit targets,
truncates the pointer returned by strchr() when assigned to a char *.
Include the missing standard header.
---
 components/net/lwip-dhcpd/dhcp_server_raw.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/components/net/lwip-dhcpd/dhcp_server_raw.c b/components/net/lwip-dhcpd/dhcp_server_raw.c
index b271ce36b95..6d4ce093f7d 100644
--- a/components/net/lwip-dhcpd/dhcp_server_raw.c
+++ b/components/net/lwip-dhcpd/dhcp_server_raw.c
@@ -35,6 +35,7 @@
 
 #include <stdio.h>
 #include <stdint.h>
+#include <string.h>
 
 #include <rtthread.h>