[4/7] batman-adv: drop unicast packets from backbone gw

Message ID 1456381808-29760-1-git-send-email-apape@phoenixcontact.com (mailing list archive)
State Superseded, archived
Delegated to: Marek Lindner
Headers

Commit Message

Andreas Pape Feb. 25, 2016, 6:30 a.m. UTC
  This patch drops unicast packets received from another backbone gw of
the same backbone network before they are forwarded to the common
backbone again. It was observed in a test setup that in rare cases
these frames lead to looping unicast traffic backbone->mesh->backbone.

Signed-off-by: Andreas Pape <apape@phoenixcontact.com>
---
 net/batman-adv/routing.c |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)

--
1.7.0.4



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Patch

diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 4dd646a..992b6cc 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -854,9 +854,11 @@  int batadv_recv_unicast_packet(struct sk_buff *skb,
 	int check, hdr_size = sizeof(*unicast_packet);
 	enum batadv_subtype subtype;
 	bool is4addr;
+	struct ethhdr *ethhdr;

 	unicast_packet = (struct batadv_unicast_packet *)skb->data;
 	unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
+	ethhdr = eth_hdr(skb);

 	is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR;
 	/* the caller function should have already pulled 2 bytes */
@@ -896,6 +898,19 @@  int batadv_recv_unicast_packet(struct sk_buff *skb,
 			}
 		}

+		/* If this is a unicast packet from another backgone gw,
+		 * drop it.
+		 */
+		orig_addr = ethhdr->h_source;
+		orig_node = batadv_orig_hash_find(bat_priv, orig_addr);
+		if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size)) {
+			batadv_dbg(BATADV_DBG_BLA, bat_priv,
+				"Dropped unicast pkt received from another backbone gw %pM.\n",
+				orig_addr);
+
+			return NET_RX_DROP;
+		}
+
 		if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
 							  hdr_size))
 			goto rx_success;