[B.A.T.M.A.N.] [PATCH v2 1/3] batman-adv: Disallow zero and mcast src address for data frames
The routing checks are validating the source mac address of the outer ethernet header. They reject every source mac address which is a broadcast address. But they also have to reject and multicast mac addresses.
Signed-off-by: Sven Eckelmann sven@narfation.org --- v2: - clarify in commit message that only the outer ethernet header is affected (thanks Linus) - split in patch 1/2 - Allow zero mac address as source address in outer header as requested by Linus --- net/batman-adv/routing.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 610f2c4..913ab51 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -357,8 +357,8 @@ int batadv_recv_icmp_packet(struct sk_buff *skb, if (is_broadcast_ether_addr(ethhdr->h_dest)) goto out;
- /* packet with broadcast sender address */ - if (is_broadcast_ether_addr(ethhdr->h_source)) + /* packet with broadcast/multicast sender address */ + if (is_multicast_ether_addr(ethhdr->h_source)) goto out;
/* not for me */ @@ -449,8 +449,8 @@ static int batadv_check_unicast_packet(struct batadv_priv *bat_priv, if (is_broadcast_ether_addr(ethhdr->h_dest)) return -EBADR;
- /* packet with broadcast sender address */ - if (is_broadcast_ether_addr(ethhdr->h_source)) + /* packet with broadcast/multicast sender address */ + if (is_multicast_ether_addr(ethhdr->h_source)) return -EBADR;
/* not for me */ @@ -1091,8 +1091,8 @@ int batadv_recv_bcast_packet(struct sk_buff *skb, if (!is_broadcast_ether_addr(ethhdr->h_dest)) goto out;
- /* packet with broadcast sender address */ - if (is_broadcast_ether_addr(ethhdr->h_source)) + /* packet with broadcast/multicast sender address */ + if (is_multicast_ether_addr(ethhdr->h_source)) goto out;
/* ignore broadcasts sent by myself */
The routing check for management frames is validating the source mac address in the outer ethernet header. It rejects every source mac address which is a broadcast address. But it also has to reject the zero-mac address and multicast mac addresses.
Signed-off-by: Sven Eckelmann sven@narfation.org --- v2: - clarify in commit message that only the outer ethernet header is affected (thanks Linus) - split in patch 1/2 --- net/batman-adv/routing.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 913ab51..e2b91e6 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -196,8 +196,8 @@ bool batadv_check_management_packet(struct sk_buff *skb, if (!is_broadcast_ether_addr(ethhdr->h_dest)) return false;
- /* packet with broadcast sender address */ - if (is_broadcast_ether_addr(ethhdr->h_source)) + /* packet with invalid sender address */ + if (!is_valid_ether_addr(ethhdr->h_source)) return false;
/* create a copy of the skb, if needed, to modify it. */
An unicast batman-adv packet cannot be transmitted to a multicast or zero mac address. So reject incoming packets which still have these classes of addresses as destination mac address in the outer ethernet header.
Signed-off-by: Sven Eckelmann sven@narfation.org --- v2: - clarify in commit message that only the outer ethernet header is affected (thanks Linus) --- net/batman-adv/routing.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index e2b91e6..65f405b 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -353,8 +353,8 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
ethhdr = eth_hdr(skb);
- /* packet with unicast indication but broadcast recipient */ - if (is_broadcast_ether_addr(ethhdr->h_dest)) + /* packet with unicast indication but non-unicast recipient */ + if (!is_valid_ether_addr(ethhdr->h_dest)) goto out;
/* packet with broadcast/multicast sender address */ @@ -445,8 +445,8 @@ static int batadv_check_unicast_packet(struct batadv_priv *bat_priv,
ethhdr = eth_hdr(skb);
- /* packet with unicast indication but broadcast recipient */ - if (is_broadcast_ether_addr(ethhdr->h_dest)) + /* packet with unicast indication but non-unicast recipient */ + if (!is_valid_ether_addr(ethhdr->h_dest)) return -EBADR;
/* packet with broadcast/multicast sender address */
b.a.t.m.a.n@lists.open-mesh.org
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Sven Eckelmann