xfrm: don't check offload_handle for nonzero

The offload_handle should be an opaque data cookie for the driver
to use, much like the data cookie for a timer or alarm callback.
Thus, the XFRM stack should not be checking for non-zero, because
the driver might use that to store an array reference, which could
be zero, or some other zero but meaningful value.

We can remove the checks for non-zero because there are plenty
other attributes also being checked to see if there is an offload
in place for the SA in question.

Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

net/ipv4/esp4_offload.c

@@ -135,8 +135,7 @@ static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
 
 	skb->encap_hdr_csum = 1;
 
-	if (!(features & NETIF_F_HW_ESP) || !x->xso.offload_handle ||
-	    (x->xso.dev != skb->dev))
+	if (!(features & NETIF_F_HW_ESP) || x->xso.dev != skb->dev)
 		esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
 	else if (!(features & NETIF_F_HW_ESP_TX_CSUM))
 		esp_features = features & ~NETIF_F_CSUM_MASK;
@@ -179,8 +178,7 @@ static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb,  netdev_features_
 	if (!xo)
 		return -EINVAL;
 
-	if (!(features & NETIF_F_HW_ESP) || !x->xso.offload_handle ||
-	    (x->xso.dev != skb->dev)) {
+	if (!(features & NETIF_F_HW_ESP) || x->xso.dev != skb->dev) {
 		xo->flags |= CRYPTO_FALLBACK;
 		hw_offload = false;
 	}

net/ipv6/esp6_offload.c

@@ -162,8 +162,7 @@ static struct sk_buff *esp6_gso_segment(struct sk_buff *skb,
 
 	skb->encap_hdr_csum = 1;
 
-	if (!(features & NETIF_F_HW_ESP) || !x->xso.offload_handle ||
-	    (x->xso.dev != skb->dev))
+	if (!(features & NETIF_F_HW_ESP) || x->xso.dev != skb->dev)
 		esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
 	else if (!(features & NETIF_F_HW_ESP_TX_CSUM))
 		esp_features = features & ~NETIF_F_CSUM_MASK;
@@ -207,8 +206,7 @@ static int esp6_xmit(struct xfrm_state *x, struct sk_buff *skb,  netdev_features
 	if (!xo)
 		return -EINVAL;
 
-	if (!(features & NETIF_F_HW_ESP) || !x->xso.offload_handle ||
-	    (x->xso.dev != skb->dev)) {
+	if (!(features & NETIF_F_HW_ESP) || x->xso.dev != skb->dev) {
 		xo->flags |= CRYPTO_FALLBACK;
 		hw_offload = false;
 	}

net/xfrm/xfrm_device.c

@@ -56,7 +56,7 @@ struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t featur
 	if (skb_is_gso(skb)) {
 		struct net_device *dev = skb->dev;
 
-		if (unlikely(!x->xso.offload_handle || (x->xso.dev != dev))) {
+		if (unlikely(x->xso.dev != dev)) {
 			struct sk_buff *segs;
 
 			/* Packet got rerouted, fixup features and segment it. */
@@ -211,8 +211,8 @@ bool xfrm_dev_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
 	if (!x->type_offload || x->encap)
 		return false;
 
-	if ((!dev || (x->xso.offload_handle && (dev == xfrm_dst_path(dst)->dev))) &&
-	     (!xdst->child->xfrm && x->type->get_mtu)) {
+	if ((!dev || (dev == xfrm_dst_path(dst)->dev)) &&
+	    (!xdst->child->xfrm && x->type->get_mtu)) {
 		mtu = x->type->get_mtu(x, xdst->child_mtu_cached);
 
 		if (skb->len <= mtu)