busybox: the DHCP client would sometimes send a superflous port unreachable frame

Fixes: WIFI-14149
Signed-off-by: John Crispin <john@phrozen.org>

patches/0087-busybox-the-DHCP-client-would-sometimes-send-a-super.patch

@@ -0,0 +1,70 @@
+From 42252a58e7396370a32444339f409a8c4635d232 Mon Sep 17 00:00:00 2001
+From: John Crispin <john@phrozen.org>
+Date: Mon, 24 Mar 2025 10:57:41 +0100
+Subject: [PATCH] busybox: the DHCP client would sometimes send a superflous
+ port unreachable frame
+
+Signed-off-by: John Crispin <john@phrozen.org>
+---
+ .../patches/600-dhcp-port-unreachable.patch   | 49 +++++++++++++++++++
+ 1 file changed, 49 insertions(+)
+ create mode 100644 package/utils/busybox/patches/600-dhcp-port-unreachable.patch
+
+diff --git a/package/utils/busybox/patches/600-dhcp-port-unreachable.patch b/package/utils/busybox/patches/600-dhcp-port-unreachable.patch
+new file mode 100644
+index 0000000000..2055f9750a
+--- /dev/null
++++ b/package/utils/busybox/patches/600-dhcp-port-unreachable.patch
+@@ -0,0 +1,49 @@
++diff --git a/package/utils/busybox/patches/202-udhcpc_reuseport.patch b/package/utils/busybox/patches/202-udhcpc_reuseport.patch
++new file mode 100644
++index 000000000000..d91d58397ee9
++--- /dev/null
+++++ b/package/utils/busybox/patches/202-udhcpc_reuseport.patch
++@@ -0,0 +1,43 @@
+++--- a/libbb/xconnect.c
++++++ b/libbb/xconnect.c
+++@@ -37,6 +37,10 @@ void FAST_FUNC setsockopt_reuseaddr(int
+++ {
+++ 	setsockopt_SOL_SOCKET_1(fd, SO_REUSEADDR);
+++ }
++++int FAST_FUNC setsockopt_reuseport(int fd)
++++{
++++	return setsockopt_SOL_SOCKET_1(fd, SO_REUSEPORT);
++++}
+++ int FAST_FUNC setsockopt_broadcast(int fd)
+++ {
+++ 	return setsockopt_SOL_SOCKET_1(fd, SO_BROADCAST);
+++--- a/include/libbb.h
++++++ b/include/libbb.h
+++@@ -734,6 +734,7 @@ int setsockopt_SOL_SOCKET_1(int fd, int
+++  * regardless of SO_REUSEADDR (unlike some other flavors of Unix).
+++  * Turn it on before you call bind(). */
+++ void setsockopt_reuseaddr(int fd) FAST_FUNC; /* On Linux this never fails. */
++++int setsockopt_reuseport(int fd) FAST_FUNC;
+++ int setsockopt_keepalive(int fd) FAST_FUNC;
+++ int setsockopt_broadcast(int fd) FAST_FUNC;
+++ int setsockopt_bindtodevice(int fd, const char *iface) FAST_FUNC;
+++--- a/networking/udhcp/packet.c
++++++ b/networking/udhcp/packet.c
+++@@ -206,6 +206,7 @@ int FAST_FUNC udhcp_send_kernel_packet(s
+++ 		goto ret_msg;
+++ 	}
+++ 	setsockopt_reuseaddr(fd);
++++	setsockopt_reuseport(fd);
+++ 
+++ 	/* If interface carrier goes down, unless we
+++ 	 * bind socket to a particular netdev, the packet
+++--- a/networking/udhcp/socket.c
++++++ b/networking/udhcp/socket.c
+++@@ -86,6 +86,7 @@ int FAST_FUNC udhcp_listen_socket(/*uint
+++ 	fd = xsocket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+++ 
+++ 	setsockopt_reuseaddr(fd);
++++	setsockopt_reuseport(fd);
+++ 	if (setsockopt_broadcast(fd) == -1)
+++ 		bb_simple_perror_msg_and_die("SO_BROADCAST");
+++ 
+-- 
+2.34.1
+