ipv4: xfrm: Eliminate ->rt_src reference in policy code.

Rearrange xfrm4_dst_lookup() so that it works by calling a helper
function __xfrm_dst_lookup() that takes an explicit flow key storage
area as an argument.

Use this new helper in xfrm4_get_saddr() so we can fetch the selected
source address from the flow instead of from rt->rt_src

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 21 insertions, 13 deletions

diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 7ff973bd02dd..981e43eaf704 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -18,38 +18,46 @@
 
 static struct xfrm_policy_afinfo xfrm4_policy_afinfo;
 
-static struct dst_entry *xfrm4_dst_lookup(struct net *net, int tos,
-                                          const xfrm_address_t *saddr,
-                                          const xfrm_address_t *daddr)
+static struct dst_entry *__xfrm4_dst_lookup(struct net *net, struct flowi4 *fl4,
+                                            int tos,
+                                            const xfrm_address_t *saddr,
+                                            const xfrm_address_t *daddr)
 {
-        struct flowi4 fl4 = {
-                .daddr = daddr->a4,
-                .flowi4_tos = tos,
-        };
         struct rtable *rt;
 
+        memset(fl4, 0, sizeof(*fl4));
+        fl4->daddr = daddr->a4;
+        fl4->flowi4_tos = tos;
         if (saddr)
-                fl4.saddr = saddr->a4;
+                fl4->saddr = saddr->a4;
 
-        rt = __ip_route_output_key(net, &fl4);
+        rt = __ip_route_output_key(net, fl4);
         if (!IS_ERR(rt))
                 return &rt->dst;
 
         return ERR_CAST(rt);
 }
 
+static struct dst_entry *xfrm4_dst_lookup(struct net *net, int tos,
+                                          const xfrm_address_t *saddr,
+                                          const xfrm_address_t *daddr)
+{
+        struct flowi4 fl4;
+
+        return __xfrm4_dst_lookup(net, &fl4, tos, saddr, daddr);
+}
+
 static int xfrm4_get_saddr(struct net *net,
                            xfrm_address_t *saddr, xfrm_address_t *daddr)
 {
         struct dst_entry *dst;
-        struct rtable *rt;
+        struct flowi4 fl4;
 
-        dst = xfrm4_dst_lookup(net, 0, NULL, daddr);
+        dst = __xfrm4_dst_lookup(net, &fl4, 0, NULL, daddr);
         if (IS_ERR(dst))
                 return -EHOSTUNREACH;
 
-        rt = (struct rtable *)dst;
-        saddr->a4 = rt->rt_src;
+        saddr->a4 = fl4.saddr;
         dst_release(dst);
         return 0;
 }