diff mbox series

batman-adv: Fix own OGM check in aggregated OGMs

Message ID 20200730222255.5109-1-linus.luessing@c0d3.blue (mailing list archive)
State Accepted, archived
Delegated to: Simon Wunderlich
Headers
Series batman-adv: Fix own OGM check in aggregated OGMs |

Commit Message

Linus Lüssing July 30, 2020, 10:22 p.m. UTC 
  The own OGM check is currently misplaced and can lead to the following
issues:

For one thing we might receive an aggregated OGM from a neighbor node
which has our own OGM in the first place. We would then not only skip
our own OGM but erroneously also any other, following OGM in the
aggregate.

For another, we might receive an OGM aggregate which has our own OGM in
a place other then the first one. Then we would wrongly not skip this
OGM, leading to populating the orginator and gateway table with ourself.

The latter seems to not only be a cosmetic issue, but there were reports
that this causes issues with various subsystems of batman-adv, too. For
instance there were reports about issues with DAT and either disabling
DAT or aggregation seemed to solve it.

Fixing these issues by applying the own OGM check not on the first OGM
in an aggregate but for each OGM in an aggregate instead.

Fixes: 667996ebeab ("batman-adv: OGMv2 - implement originators logic")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
 net/batman-adv/bat_v_ogm.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c
index 0f8495b9..717fe657 100644
--- a/net/batman-adv/bat_v_ogm.c
+++ b/net/batman-adv/bat_v_ogm.c
@@ -881,6 +881,12 @@  static void batadv_v_ogm_process(const struct sk_buff *skb, int ogm_offset,
 		   ntohl(ogm_packet->seqno), ogm_throughput, ogm_packet->ttl,
 		   ogm_packet->version, ntohs(ogm_packet->tvlv_len));
 
+	if (batadv_is_my_mac(bat_priv, ogm_packet->orig)) {
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "Drop packet: originator packet from ourself\n");
+		return;
+	}
+
 	/* If the throughput metric is 0, immediately drop the packet. No need
 	 * to create orig_node / neigh_node for an unusable route.
 	 */
@@ -1008,11 +1014,6 @@  int batadv_v_ogm_packet_recv(struct sk_buff *skb,
 	if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
 		goto free_skb;
 
-	ogm_packet = (struct batadv_ogm2_packet *)skb->data;
-
-	if (batadv_is_my_mac(bat_priv, ogm_packet->orig))
-		goto free_skb;
-
 	batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
 	batadv_add_counter(bat_priv, BATADV_CNT_MGMT_RX_BYTES,
 			   skb->len + ETH_HLEN);