commit dea9343d617632c17a9db459f2b7dcb4df0d10ed
author Olof Winge <olof@skyshaper.net> Fri May 27 10:13:13 2022 +0200
committer Marti Bolivar <marti.bolivar@nordicsemi.no> Fri May 27 15:46:44 2022 -0700
tree 77ec5fb50c46a43908c28bde412b9530c88598c6
parent 67598965fbf09ae449e8d52a2056da3fe24a17a2

net: ipv4: Accept unspecified src address if dst is broadcast

To be able to accept DHCP discover/request incoming packets the ip stack
neeeds to accept unspecified src addr if the destination is broadcast
address.

Signed-off-by: Olof Winge <olof@skyshaper.net>

subsys/net/ip/ipv4.c

diff --git a/subsys/net/ip/ipv4.c b/subsys/net/ip/ipv4.c
index 32dd639..a04fbbc 100644
--- a/subsys/net/ip/ipv4.c
+++ b/subsys/net/ip/ipv4.c
@@ -278,7 +278,8 @@
 		goto drop;
 	}
 
-	if (net_ipv4_is_addr_unspecified((struct in_addr *)hdr->src)) {
+	if (net_ipv4_is_addr_unspecified((struct in_addr *)hdr->src) &&
+	    !net_ipv4_is_addr_bcast(net_pkt_iface(pkt), (struct in_addr *)hdr->dst)) {
 		NET_DBG("DROP: src addr is %s", "unspecified");
 		goto drop;
 	}