From 40fb70f3aa0a67d28a30c854d4e7aa10b0511db9 Mon Sep 17 00:00:00 2001 From: Alexey Kodanev Date: Fri, 13 Mar 2015 19:13:53 +0300 Subject: vxlan: fix wrong usage of VXLAN_VID_MASK commit dfd8645ea1bd9127 wrongly assumes that VXLAN_VDI_MASK includes eight lower order reserved bits of VNI field that are using for remote checksum offload. Right now, when VNI number greater then 0xffff, vxlan_udp_encap_recv() will always return with 'bad_flag' error, reducing the usable vni range from 0..16777215 to 0..65535. Also, it doesn't really check whether RCO bits processed or not. Fix it by adding new VNI mask which has all 32 bits of VNI field: 24 bits for id and 8 bits for other usage. Signed-off-by: Alexey Kodanev Signed-off-by: David S. Miller diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 1e0a775..f8528a4 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -1218,7 +1218,7 @@ static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb) goto drop; flags &= ~VXLAN_HF_RCO; - vni &= VXLAN_VID_MASK; + vni &= VXLAN_VNI_MASK; } /* For backwards compatibility, only allow reserved fields to be @@ -1239,7 +1239,7 @@ static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb) flags &= ~VXLAN_GBP_USED_BITS; } - if (flags || (vni & ~VXLAN_VID_MASK)) { + if (flags || vni & ~VXLAN_VNI_MASK) { /* If there are any unprocessed flags remaining treat * this as a malformed packet. This behavior diverges from * VXLAN RFC (RFC7348) which stipulates that bits in reserved diff --git a/include/net/vxlan.h b/include/net/vxlan.h index eabd3a0..c73e7ab 100644 --- a/include/net/vxlan.h +++ b/include/net/vxlan.h @@ -91,6 +91,7 @@ struct vxlanhdr { #define VXLAN_N_VID (1u << 24) #define VXLAN_VID_MASK (VXLAN_N_VID - 1) +#define VXLAN_VNI_MASK (VXLAN_VID_MASK << 8) #define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr)) struct vxlan_metadata { -- cgit v0.10.2