tcp_metrics: Rewrite tcp_metrics_flush_all

Rewrite tcp_metrics_flush_all so that it can cope with entries from
different network namespaces on it's hash chain.

This is based on the logic in tcp_metrics_nl_cmd_del for deleting
a selection of entries from a tcp metrics hash chain.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 10 deletions

diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
index 0d07e14f2ca5..baccb070427d 100644
--- a/net/ipv4/tcp_metrics.c
+++ b/net/ipv4/tcp_metrics.c
@@ -1051,18 +1051,19 @@ static void tcp_metrics_flush_all(struct net *net)
         unsigned int row;
 
         for (row = 0; row < max_rows; row++, hb++) {
+                struct tcp_metrics_block __rcu **pp;
                 spin_lock_bh(&tcp_metrics_lock);
-                tm = deref_locked_genl(hb->chain);
-                if (tm)
-                        hb->chain = NULL;
-                spin_unlock_bh(&tcp_metrics_lock);
-                while (tm) {
-                        struct tcp_metrics_block *next;
-
-                        next = deref_genl(tm->tcpm_next);
-                        kfree_rcu(tm, rcu_head);
-                        tm = next;
+                pp = &hb->chain;
+                for (tm = deref_locked_genl(*pp); tm;
+                     tm = deref_locked_genl(*pp)) {
+                        if (net_eq(tm_net(tm), net)) {
+                                *pp = tm->tcpm_next;
+                                kfree_rcu(tm, rcu_head);
+                        } else {
+                                pp = &tm->tcpm_next;
+                        }
                 }
+                spin_unlock_bh(&tcp_metrics_lock);
         }
 }