vti4: Check the tunnel endpoints of the xfrm state and the vti interface
The tunnel endpoints of the xfrm_state we got from the xfrm_lookup
must match the tunnel endpoints of the vti interface. This patch
ensures this matching.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index 9369b7c..9471893 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -123,10 +123,32 @@
return 0;
}
+static bool vti_state_check(const struct xfrm_state *x, __be32 dst, __be32 src)
+{
+ xfrm_address_t *daddr = (xfrm_address_t *)&dst;
+ xfrm_address_t *saddr = (xfrm_address_t *)&src;
+
+ /* if there is no transform then this tunnel is not functional.
+ * Or if the xfrm is not mode tunnel.
+ */
+ if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
+ x->props.family != AF_INET)
+ return false;
+
+ if (!dst)
+ return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET);
+
+ if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET))
+ return false;
+
+ return true;
+}
+
static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
struct flowi *fl)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
+ struct ip_tunnel_parm *parms = &tunnel->parms;
struct dst_entry *dst = skb_dst(skb);
struct net_device *tdev; /* Device to other host */
int err;
@@ -143,15 +165,12 @@
goto tx_error_icmp;
}
- /* if there is no transform then this tunnel is not functional.
- * Or if the xfrm is not mode tunnel.
- */
- if (!dst->xfrm ||
- dst->xfrm->props.mode != XFRM_MODE_TUNNEL) {
+ if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) {
dev->stats.tx_carrier_errors++;
dst_release(dst);
goto tx_error_icmp;
}
+
tdev = dst->dev;
if (tdev == dev) {