ipv6: remove from fib tree aged out RTF_CACHE dst

[linux.git] / net / ipv6 / route.c

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index efecdcff5055af9a252b466a166d548a0ee0ce3a..074fac966018be8a3943ccc438045f77718f98a1 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1575,7 +1575,13 @@ static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
 {
        struct rt6_info *rt = rt6_ex->rt6i;
 
-       if (atomic_read(&rt->dst.__refcnt) == 1 &&
+       /* we are pruning and obsoleting aged-out and non gateway exceptions
+        * even if others have still references to them, so that on next
+        * dst_check() such references can be dropped.
+        * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when
+        * expired, independently from their aging, as per RFC 8201 section 4
+        */
+       if (!(rt->rt6i_flags & RTF_EXPIRES) &&
            time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
                RT6_TRACE("aging clone %p\n", rt);
                rt6_remove_exception(bucket, rt6_ex);
@@ -1595,6 +1601,10 @@ static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
                        rt6_remove_exception(bucket, rt6_ex);
                        return;
                }
+       } else if (__rt6_check_expired(rt)) {
+               RT6_TRACE("purging expired route %p\n", rt);
+               rt6_remove_exception(bucket, rt6_ex);
+               return;
        }
        gc_args->more++;
 }