From: Kazunori Miyazawa <kazunori@miyazawa.org>

[XFRM] Call dst_check() with appropriate cookie

This fixes infinite loop issue with IPv6 tunnel mode.
Signed-off-by: Kazunori Miyazawa <kazunori@miyazawa.org>
Signed-off-by: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/xfrm.h

@@ -515,6 +515,8 @@ struct xfrm_dst
 	struct dst_entry *route;
 	u32 route_mtu_cached;
 	u32 child_mtu_cached;
+	u32 route_cookie;
+	u32 path_cookie;
 };
 
 static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)

net/ipv6/xfrm6_policy.c

@@ -113,6 +113,8 @@ __xfrm6_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int
 
 		xdst = (struct xfrm_dst *)dst1;
 		xdst->route = &rt->u.dst;
+		if (rt->rt6i_node)
+			xdst->route_cookie = rt->rt6i_node->fn_sernum;
 
 		dst1->next = dst_prev;
 		dst_prev = dst1;
@@ -137,6 +139,8 @@ __xfrm6_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int
 
 	dst_prev->child = &rt->u.dst;
 	dst->path = &rt->u.dst;
+	if (rt->rt6i_node)
+		((struct xfrm_dst *)dst)->path_cookie = rt->rt6i_node->fn_sernum;
 
 	*dst_p = dst;
 	dst = dst_prev;

net/xfrm/xfrm_policy.c

@@ -1136,7 +1136,7 @@ int xfrm_bundle_ok(struct xfrm_dst *first, struct flowi *fl, int family)
 	struct xfrm_dst *last;
 	u32 mtu;
 
-	if (!dst_check(dst->path, 0) ||
+	if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
 	    (dst->dev && !netif_running(dst->dev)))
 		return 0;
 
@@ -1156,7 +1156,7 @@ int xfrm_bundle_ok(struct xfrm_dst *first, struct flowi *fl, int family)
 			xdst->child_mtu_cached = mtu;
 		}
 
-		if (!dst_check(xdst->route, 0))
+		if (!dst_check(xdst->route, xdst->route_cookie))
 			return 0;
 		mtu = dst_mtu(xdst->route);
 		if (xdst->route_mtu_cached != mtu) {