diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index c532884f4fec..2dc7a1d97686 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -852,9 +852,18 @@ arp_notify - BOOLEAN or hardware address changes. arp_accept - BOOLEAN - Define behavior when gratuitous arp replies are received: - 0 - drop gratuitous arp frames - 1 - accept gratuitous arp frames + Define behavior for gratuitous ARP frames who's IP is not + already present in the ARP table: + 0 - don't create new entries in the ARP table + 1 - create new entries in the ARP table + + Both replies and requests type gratuitous arp will trigger the + ARP table to be updated, if this setting is on. + + If the ARP table already contains the IP address of the + gratuitous arp frame, the arp table will be updated regardless + if this setting is on or off. + app_solicit - INTEGER The maximum number of probes to send to the user space ARP daemon diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index 078709233bc4..1940b4df7699 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -907,7 +907,8 @@ static int arp_process(struct sk_buff *skb) devices (strip is candidate) */ if (n == NULL && - arp->ar_op == htons(ARPOP_REPLY) && + (arp->ar_op == htons(ARPOP_REPLY) || + (arp->ar_op == htons(ARPOP_REQUEST) && tip == sip)) && inet_addr_type(net, sip) == RTN_UNICAST) n = __neigh_lookup(&arp_tbl, &sip, dev, 1); }