flowcache: Fix resource leaks on namespace exit.

We leak an active timer, the hotcpu notifier and all allocated
resources when we exit a namespace. Fix this by introducing a
flow_cache_fini() function where we release the resources before
we exit.

Fixes: ca925cf1534e ("flowcache: Make flow cache name space aware")
Reported-by: Jakub Kicinski <moorray3@wp.pl>
Tested-by: Jakub Kicinski <moorray3@wp.pl>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 25 insertions, 1 deletions

diff --git a/net/core/flow.c b/net/core/flow.c
index 102f8ea2eb6e..31cfb365e0c6 100644
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -484,3 +484,22 @@ err:
         return -ENOMEM;
 }
 EXPORT_SYMBOL(flow_cache_init);
+
+void flow_cache_fini(struct net *net)
+{
+        int i;
+        struct flow_cache *fc = &net->xfrm.flow_cache_global;
+
+        del_timer_sync(&fc->rnd_timer);
+        unregister_hotcpu_notifier(&fc->hotcpu_notifier);
+
+        for_each_possible_cpu(i) {
+                struct flow_cache_percpu *fcp = per_cpu_ptr(fc->percpu, i);
+                kfree(fcp->hash_table);
+                fcp->hash_table = NULL;
+        }
+
+        free_percpu(fc->percpu);
+        fc->percpu = NULL;
+}
+EXPORT_SYMBOL(flow_cache_fini);
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index a75fae4b045a..f02f511b7107 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2913,15 +2913,19 @@ static int __net_init xfrm_net_init(struct net *net)
         rv = xfrm_sysctl_init(net);
         if (rv < 0)
                 goto out_sysctl;
+        rv = flow_cache_init(net);
+        if (rv < 0)
+                goto out;
 
         /* Initialize the per-net locks here */
         spin_lock_init(&net->xfrm.xfrm_state_lock);
         rwlock_init(&net->xfrm.xfrm_policy_lock);
         mutex_init(&net->xfrm.xfrm_cfg_mutex);
 
-        flow_cache_init(net);
         return 0;
 
+out:
+        xfrm_sysctl_fini(net);
 out_sysctl:
         xfrm_policy_fini(net);
 out_policy:
@@ -2934,6 +2938,7 @@ out_statistics:
 
 static void __net_exit xfrm_net_exit(struct net *net)
 {
+        flow_cache_fini(net);
         xfrm_sysctl_fini(net);
         xfrm_policy_fini(net);
         xfrm_state_fini(net);