We never want multicast MAC addresses in the Distributed ARP Table, so it's best to completely ignore ARP packets containing them where we expect unicast addresses.
Signed-off-by: Matthias Schiffer <[email protected]> --- distributed-arp-table.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/distributed-arp-table.c b/distributed-arp-table.c index a35466a..c89a01e 100644 --- a/distributed-arp-table.c +++ b/distributed-arp-table.c @@ -738,6 +738,7 @@ static uint16_t batadv_arp_get_type(struct batadv_priv *bat_priv, struct arphdr *arphdr; struct ethhdr *ethhdr; __be32 ip_src, ip_dst; + uint8_t *hw_src, *hw_dst; uint16_t type = 0; /* pull the ethernet header */ @@ -782,6 +783,18 @@ static uint16_t batadv_arp_get_type(struct batadv_priv *bat_priv, ipv4_is_zeronet(ip_dst) || ipv4_is_lbcast(ip_dst)) goto out; + hw_src = batadv_arp_hw_src(skb, hdr_size); + if (is_zero_ether_addr(hw_src) || is_multicast_ether_addr(hw_src)) + goto out; + + /* we don't care for the destination MAC address in ARP requests */ + if (arphdr->ar_op != htons(ARPOP_REQUEST)) { + hw_dst = batadv_arp_hw_dst(skb, hdr_size); + if (is_zero_ether_addr(hw_dst) || + is_multicast_ether_addr(hw_dst)) + goto out; + } + type = ntohs(arphdr->ar_op); out: return type; -- 1.8.1.1
