netdev - [PATCH net-next 01/10] vxlan: only migrate dynamic FDB entries

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Tue,  4 Jun 2013 21:24:05 -0700
From:	Stephen Hemminger <stephen@...workplumber.org>
To:	davem@...emloft.net
Cc:	netdev@...r.kernel.org,
	Stephen Hemminger <stephen@...workplumber.org>
Subject: [PATCH net-next 01/10] vxlan: only migrate dynamic FDB entries

Only migrate dynamic forwarding table entries, don't modify
static entries. If packet received from incorrect source IP address
assume it is an imposter and drop it.

Signed-off-by: Stephen Hemminger <stephen@...workplumber.org>

---
Should go to -stable as well.
---
 drivers/net/vxlan.c |   17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 8111565..536082a 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -604,8 +604,8 @@ skip:
 /* Watch incoming packets to learn mapping between Ethernet address
  * and Tunnel endpoint.
  */
-static void vxlan_snoop(struct net_device *dev,
-			__be32 src_ip, const u8 *src_mac)
+static int vxlan_snoop(struct net_device *dev,
+		       __be32 src_ip, const u8 *src_mac)
 {
 	struct vxlan_dev *vxlan = netdev_priv(dev);
 	struct vxlan_fdb *f;
@@ -614,7 +614,11 @@ static void vxlan_snoop(struct net_device *dev,
 	f = vxlan_find_mac(vxlan, src_mac);
 	if (likely(f)) {
 		if (likely(f->remote.remote_ip == src_ip))
-			return;
+			return 0;
+
+		/* Don't migrate static entries, drop packets */
+		if (!(f->flags & NTF_SELF))
+			return 1;
 
 		if (net_ratelimit())
 			netdev_info(dev,
@@ -634,6 +638,8 @@ static void vxlan_snoop(struct net_device *dev,
 				       0, NTF_SELF);
 		spin_unlock(&vxlan->hash_lock);
 	}
+
+	return 0;
 }
 
 
@@ -766,8 +772,9 @@ static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
 			       vxlan->dev->dev_addr) == 0)
 		goto drop;
 
-	if (vxlan->flags & VXLAN_F_LEARN)
-		vxlan_snoop(skb->dev, oip->saddr, eth_hdr(skb)->h_source);
+	if ((vxlan->flags & VXLAN_F_LEARN) &&
+	    vxlan_snoop(skb->dev, oip->saddr, eth_hdr(skb)->h_source))
+		goto drop;
 
 	__skb_tunnel_rx(skb, vxlan->dev);
 	skb_reset_network_header(skb);
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html