[PATCH ipsec-next] xfrm: check for xdo_dev_state_free

[Shannon Nelson]

The current XFRM code assumes that we've implemented the
xdo_dev_state_free() callback, even if it is meaningless to the driver.
This patch adds a check for it before calling, as done in other APIs,
and is done for the xdo_state_offload_ok() callback.

Also, we add a check for the required add and delete functions up front
at registration time to be sure both are defined, and complain if not.

Signed-off-by: Shannon Nelson <shannon.nel...@oracle.com>
---
 include/net/xfrm.h     |  3 ++-
 net/xfrm/xfrm_device.c | 18 ++++++++++++++----
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index e015e16..dfabd04 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1891,7 +1891,8 @@ static inline void xfrm_dev_state_free(struct xfrm_state 
*x)
         struct net_device *dev = xso->dev;
 
        if (dev && dev->xfrmdev_ops) {
-               dev->xfrmdev_ops->xdo_dev_state_free(x);
+               if (dev->xfrmdev_ops->xdo_dev_state_free)
+                       dev->xfrmdev_ops->xdo_dev_state_free(x);
                xso->dev = NULL;
                dev_put(dev);
        }
diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c
index 30e5746..0df1cc2 100644
--- a/net/xfrm/xfrm_device.c
+++ b/net/xfrm/xfrm_device.c
@@ -144,11 +144,21 @@ EXPORT_SYMBOL_GPL(xfrm_dev_offload_ok);
 
 static int xfrm_dev_register(struct net_device *dev)
 {
-       if ((dev->features & NETIF_F_HW_ESP) && !dev->xfrmdev_ops)
-               return NOTIFY_BAD;
-       if ((dev->features & NETIF_F_HW_ESP_TX_CSUM) &&
-           !(dev->features & NETIF_F_HW_ESP))
+       if (!(dev->features & NETIF_F_HW_ESP)) {
+               if (dev->features & NETIF_F_HW_ESP_TX_CSUM) {
+                       netdev_err(dev, "NETIF_F_HW_ESP_TX_CSUM without 
NETIF_F_HW_ESP\n");
+                       return NOTIFY_BAD;
+               } else {
+                       return NOTIFY_DONE;
+               }
+       }
+
+       if (!(dev->xfrmdev_ops &&
+             dev->xfrmdev_ops->xdo_dev_state_add &&
+             dev->xfrmdev_ops->xdo_dev_state_delete)) {
+               netdev_err(dev, "add or delete function missing from 
xfrmdev_ops\n");
                return NOTIFY_BAD;
+       }
 
        return NOTIFY_DONE;
 }
-- 
2.7.4