1 files changed, 28 insertions, 0 deletions

diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c
index e4cba56a534..cac02ad1425 100644
--- a/net/ipv4/inetpeer.c
+++ b/net/ipv4/inetpeer.c
@@ -86,10 +86,36 @@ void inet_peer_base_init(struct inet_peer_base *bp)
 {
         bp->root = peer_avl_empty_rcu;
         seqlock_init(&bp->lock);
+        bp->flush_seq = ~0U;
         bp->total = 0;
 }
 EXPORT_SYMBOL_GPL(inet_peer_base_init);
 
+static atomic_t v4_seq = ATOMIC_INIT(0);
+static atomic_t v6_seq = ATOMIC_INIT(0);
+
+static atomic_t *inetpeer_seq_ptr(int family)
+{
+        return (family == AF_INET ? &v4_seq : &v6_seq);
+}
+
+static inline void flush_check(struct inet_peer_base *base, int family)
+{
+        atomic_t *fp = inetpeer_seq_ptr(family);
+
+        if (unlikely(base->flush_seq != atomic_read(fp))) {
+                inetpeer_invalidate_tree(base);
+                base->flush_seq = atomic_read(fp);
+        }
+}
+
+void inetpeer_invalidate_family(int family)
+{
+        atomic_t *fp = inetpeer_seq_ptr(family);
+
+        atomic_inc(fp);
+}
+
 #define PEER_MAXDEPTH 40 /* sufficient for about 2^27 nodes */
 
 /* Exported for sysctl_net_ipv4.  */
@@ -437,6 +463,8 @@ struct inet_peer *inet_getpeer(struct inet_peer_base *base,
         unsigned int sequence;
         int invalidated, gccnt = 0;
 
+        flush_check(base, daddr->family);
+
         /* Attempt a lockless lookup first.
          * Because of a concurrent writer, we might not find an existing entry.
          */