Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2c38de4c authored Jun 16, 2011 by Nicolas Cavallari Committed by Patrick McHardy Jun 16, 2011

netfilter: fix looped (broad|multi)cast's MAC handling



By default, when broadcast or multicast packet are sent from a local
application, they are sent to the interface then looped by the kernel
to other local applications, going throught netfilter hooks in the
process.

These looped packet have their MAC header removed from the skb by the
kernel looping code. This confuse various netfilter's netlink queue,
netlink log and the legacy ip_queue, because they try to extract a
hardware address from these packets, but extracts a part of the IP
header instead.

This patch prevent NFQUEUE, NFLOG and ip_QUEUE to include a MAC header
if there is none in the packet.

Signed-off-by: Nicolas Cavallari <cavallar@lri.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>

parent db898aa2

net/ipv4/netfilter/ip_queue.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -203,7 +203,8 @@ ipq_build_packet_message(struct nf_queue_entry entry, int errp)
		else
		pmsg->outdev_name[0] = '\0';

		if (entry->indev && entry->skb->dev) {
		if (entry->indev && entry->skb->dev &&
		entry->skb->mac_header != entry->skb->network_header) {
		pmsg->hw_type = entry->skb->dev->type;
		pmsg->hw_addrlen = dev_parse_header(entry->skb,
		pmsg->hw_addr);

net/ipv6/netfilter/ip6_queue.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -204,7 +204,8 @@ ipq_build_packet_message(struct nf_queue_entry entry, int errp)
		else
		pmsg->outdev_name[0] = '\0';

		if (entry->indev && entry->skb->dev) {
		if (entry->indev && entry->skb->dev &&
		entry->skb->mac_header != entry->skb->network_header) {
		pmsg->hw_type = entry->skb->dev->type;
		pmsg->hw_addrlen = dev_parse_header(entry->skb, pmsg->hw_addr);
		}

net/netfilter/nfnetlink_log.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -456,7 +456,8 @@ __build_packet_message(struct nfulnl_instance *inst,
		if (skb->mark)
		NLA_PUT_BE32(inst->skb, NFULA_MARK, htonl(skb->mark));

		if (indev && skb->dev) {
		if (indev && skb->dev &&
		skb->mac_header != skb->network_header) {
		struct nfulnl_msg_packet_hw phw;
		int len = dev_parse_header(skb, phw.hw_addr);
		if (len > 0) {

net/netfilter/nfnetlink_queue.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -335,7 +335,8 @@ nfqnl_build_packet_message(struct nfqnl_instance *queue,
		if (entskb->mark)
		NLA_PUT_BE32(skb, NFQA_MARK, htonl(entskb->mark));

		if (indev && entskb->dev) {
		if (indev && entskb->dev &&
		entskb->mac_header != entskb->network_header) {
		struct nfqnl_msg_packet_hw phw;
		int len = dev_parse_header(entskb, phw.hw_addr);
		if (len) {