ipv4: add reference counting to metrics

[karo-tx-linux.git] / net / ipv4 / fib_semantics.c

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index da449ddb8cc172bd9091c00057a69a095f98b56d..ad9ad4aab5da7c7d11c3b80edbdfcbdd3d7153fe 100644 (file)
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -203,6 +203,7 @@ static void rt_fibinfo_free_cpus(struct rtable __rcu * __percpu *rtp)
 static void free_fib_info_rcu(struct rcu_head *head)
 {
        struct fib_info *fi = container_of(head, struct fib_info, rcu);
+       struct dst_metrics *m;
 
        change_nexthops(fi) {
                if (nexthop_nh->nh_dev)
@@ -213,8 +214,9 @@ static void free_fib_info_rcu(struct rcu_head *head)
                rt_fibinfo_free(&nexthop_nh->nh_rth_input);
        } endfor_nexthops(fi);
 
-       if (fi->fib_metrics != (u32 *) dst_default_metrics)
-               kfree(fi->fib_metrics);
+       m = fi->fib_metrics;
+       if (m != &dst_default_metrics && atomic_dec_and_test(&m->refcnt))
+               kfree(m);
        kfree(fi);
 }
 
@@ -971,11 +973,11 @@ fib_convert_metrics(struct fib_info *fi, const struct fib_config *cfg)
                        val = 255;
                if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
                        return -EINVAL;
-               fi->fib_metrics[type - 1] = val;
+               fi->fib_metrics->metrics[type - 1] = val;
        }
 
        if (ecn_ca)
-               fi->fib_metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
+               fi->fib_metrics->metrics[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
 
        return 0;
 }
@@ -1033,11 +1035,12 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
                goto failure;
        fib_info_cnt++;
        if (cfg->fc_mx) {
-               fi->fib_metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
+               fi->fib_metrics = kzalloc(sizeof(*fi->fib_metrics), GFP_KERNEL);
                if (!fi->fib_metrics)
                        goto failure;
+               atomic_set(&fi->fib_metrics->refcnt, 1);
        } else
-               fi->fib_metrics = (u32 *) dst_default_metrics;
+               fi->fib_metrics = (struct dst_metrics *)&dst_default_metrics;
 
        fi->fib_net = net;
        fi->fib_protocol = cfg->fc_protocol;
@@ -1238,7 +1241,7 @@ int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
        if (fi->fib_priority &&
            nla_put_u32(skb, RTA_PRIORITY, fi->fib_priority))
                goto nla_put_failure;
-       if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
+       if (rtnetlink_put_metrics(skb, fi->fib_metrics->metrics) < 0)
                goto nla_put_failure;
 
        if (fi->fib_prefsrc &&