+/* called under rcu_read_lock */
+static void vrf_get_saddr(struct net_device *dev, struct flowi4 *fl4)
+{
+ struct fib_result res = { .tclassid = 0 };
+ struct net *net = dev_net(dev);
+ u32 orig_tos = fl4->flowi4_tos;
+ u8 flags = fl4->flowi4_flags;
+ u8 scope = fl4->flowi4_scope;
+ u8 tos = RT_FL_TOS(fl4);
+
+ if (unlikely(!fl4->daddr))
+ return;
+
+ fl4->flowi4_flags |= FLOWI_FLAG_SKIP_NH_OIF;
+ fl4->flowi4_iif = LOOPBACK_IFINDEX;
+ fl4->flowi4_tos = tos & IPTOS_RT_MASK;
+ fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
+ RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
+
+ if (!fib_lookup(net, fl4, &res, 0)) {
+ if (res.type == RTN_LOCAL)
+ fl4->saddr = res.fi->fib_prefsrc ? : fl4->daddr;
+ else
+ fib_select_path(net, &res, fl4, -1);
+ }
+
+ fl4->flowi4_flags = flags;
+ fl4->flowi4_tos = orig_tos;
+ fl4->flowi4_scope = scope;
+}
+