xfrm: don't skip free of empty state in acquire policy

In destruction flow, the assignment of NULL to xso->dev
caused to skip of xfrm_dev_state_free() call, which was
called in xfrm_state_put(to_put) routine.

Instead of open-coded variant of xfrm_dev_state_delete() and
xfrm_dev_state_free(), let's use them directly.

Fixes: f8a70afa ("xfrm: add TX datapath support for IPsec packet offload mode")
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

include/net/xfrm.h

@@ -1984,6 +1984,7 @@ static inline void xfrm_dev_state_free(struct xfrm_state *x)
 		if (dev->xfrmdev_ops->xdo_dev_state_free)
 			dev->xfrmdev_ops->xdo_dev_state_free(x);
 		xso->dev = NULL;
+		xso->type = XFRM_DEV_OFFLOAD_UNSPECIFIED;
 		netdev_put(dev, &xso->dev_tracker);
 	}
 }

net/xfrm/xfrm_state.c

@@ -1324,12 +1324,8 @@ xfrm_state_find(const xfrm_address_t *daddr, const xfrm_address_t *saddr,
 			struct xfrm_dev_offload *xso = &x->xso;
 
 			if (xso->type == XFRM_DEV_OFFLOAD_PACKET) {
-				xso->dev->xfrmdev_ops->xdo_dev_state_delete(x);
-				xso->dir = 0;
-				netdev_put(xso->dev, &xso->dev_tracker);
-				xso->dev = NULL;
-				xso->real_dev = NULL;
-				xso->type = XFRM_DEV_OFFLOAD_UNSPECIFIED;
+				xfrm_dev_state_delete(x);
+				xfrm_dev_state_free(x);
 			}
 #endif
 			x->km.state = XFRM_STATE_DEAD;