xfrm6: release dev before returning error

We forget to call dev_put() on error path in xfrm6_fill_dst(),
its caller doesn't handle this.

Cc: Herbert Xu <[email protected]>
Cc: Steffen Klassert <[email protected]>
Cc: David S. Miller <[email protected]>
Signed-off-by: Cong Wang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: Cong Wang

net/ipv6/xfrm6_policy.c

@@ -103,8 +103,10 @@ static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
 	dev_hold(dev);
 
 	xdst->u.rt6.rt6i_idev = in6_dev_get(dev);
-	if (!xdst->u.rt6.rt6i_idev)
+	if (!xdst->u.rt6.rt6i_idev) {
+		dev_put(dev);
 		return -ENODEV;
+	}
 
 	rt6_transfer_peer(&xdst->u.rt6, rt);