net: ethernet: Send sender IP address in ARP announce packets

In addition to checking that the ARP entry does not exist as the
implementation is done currently, also check if the ARP packet
is due to IPv4 link local address configuration. In both cases
use the provided IPv4 address instead of the one set for the
interface.

Signed-off-by: Patrik Flykt <[email protected]>

Author: pfl

subsys/net/l2/ethernet/arp.c

@@ -297,10 +297,10 @@ static inline struct net_pkt *arp_prepare(struct net_if *iface,
 	memcpy(hdr->src_hwaddr.addr, net_pkt_lladdr_src(pkt)->addr,
 	       sizeof(struct net_eth_addr));
 
-	if (entry) {
-		my_addr = if_get_addr(entry->iface, current_ip);
-	} else {
+	if (!entry || (pkt != NULL && net_pkt_ipv4_auto(pkt))) {
 		my_addr = current_ip;
+	} else {
+		my_addr = if_get_addr(entry->iface, current_ip);
 	}
 
 	if (my_addr) {