vmxnet3: fix incorrect dereference when rxvlan is disabled

vmxnet3_get_hdr_len() is used to calculate the header length which in
turn is used to calculate the gso_size for skb. When rxvlan offload is
disabled, vlan tag is present in the header and the function references
ip header from sizeof(ethhdr) and leads to incorrect pointer reference.

This patch fixes this issue by taking sizeof(vlan_ethhdr) into account
if vlan tag is present and correctly references the ip hdr.

Signed-off-by: Ronak Doshi <doshir@vmware.com>
Acked-by: Guolin Yang <gyang@vmware.com>
Acked-by: Louis Luo <llouis@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/vmxnet3/vmxnet3_drv.c

@@ -1218,6 +1218,7 @@ vmxnet3_get_hdr_len(struct vmxnet3_adapter *adapter, struct sk_buff *skb,
 	union {
 		void *ptr;
 		struct ethhdr *eth;
+		struct vlan_ethhdr *veth;
 		struct iphdr *ipv4;
 		struct ipv6hdr *ipv6;
 		struct tcphdr *tcp;
@@ -1228,16 +1229,24 @@ vmxnet3_get_hdr_len(struct vmxnet3_adapter *adapter, struct sk_buff *skb,
 	if (unlikely(sizeof(struct iphdr) + sizeof(struct tcphdr) > maplen))
 		return 0;
 
+	if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
+	    skb->protocol == cpu_to_be16(ETH_P_8021AD))
+		hlen = sizeof(struct vlan_ethhdr);
+	else
+		hlen = sizeof(struct ethhdr);
+
 	hdr.eth = eth_hdr(skb);
 	if (gdesc->rcd.v4) {
-		BUG_ON(hdr.eth->h_proto != htons(ETH_P_IP));
-		hdr.ptr += sizeof(struct ethhdr);
+		BUG_ON(hdr.eth->h_proto != htons(ETH_P_IP) &&
+		       hdr.veth->h_vlan_encapsulated_proto != htons(ETH_P_IP));
+		hdr.ptr += hlen;
 		BUG_ON(hdr.ipv4->protocol != IPPROTO_TCP);
 		hlen = hdr.ipv4->ihl << 2;
 		hdr.ptr += hdr.ipv4->ihl << 2;
 	} else if (gdesc->rcd.v6) {
-		BUG_ON(hdr.eth->h_proto != htons(ETH_P_IPV6));
-		hdr.ptr += sizeof(struct ethhdr);
+		BUG_ON(hdr.eth->h_proto != htons(ETH_P_IPV6) &&
+		       hdr.veth->h_vlan_encapsulated_proto != htons(ETH_P_IPV6));
+		hdr.ptr += hlen;
 		/* Use an estimated value, since we also need to handle
 		 * TSO case.
 		 */

drivers/net/vmxnet3/vmxnet3_int.h

@@ -69,10 +69,10 @@
 /*
  * Version numbers
  */
-#define VMXNET3_DRIVER_VERSION_STRING   "1.4.13.0-k"
+#define VMXNET3_DRIVER_VERSION_STRING   "1.4.14.0-k"
 
 /* a 32-bit int, each byte encode a verion number in VMXNET3_DRIVER_VERSION */
-#define VMXNET3_DRIVER_VERSION_NUM      0x01040d00
+#define VMXNET3_DRIVER_VERSION_NUM      0x01040e00
 
 #if defined(CONFIG_PCI_MSI)
 	/* RSS only makes sense if MSI-X is supported. */