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Diffstat (limited to 'net/core/net_namespace.c')
-rw-r--r--net/core/net_namespace.c79
1 files changed, 48 insertions, 31 deletions
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 989434f36f96..50fdc1b59777 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -39,6 +39,9 @@ EXPORT_SYMBOL(init_net);
static bool init_net_initialized;
+#define MIN_PERNET_OPS_ID \
+ ((sizeof(struct net_generic) + sizeof(void *) - 1) / sizeof(void *))
+
#define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */
static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS;
@@ -46,27 +49,28 @@ static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS;
static struct net_generic *net_alloc_generic(void)
{
struct net_generic *ng;
- size_t generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]);
+ unsigned int generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]);
ng = kzalloc(generic_size, GFP_KERNEL);
if (ng)
- ng->len = max_gen_ptrs;
+ ng->s.len = max_gen_ptrs;
return ng;
}
-static int net_assign_generic(struct net *net, int id, void *data)
+static int net_assign_generic(struct net *net, unsigned int id, void *data)
{
struct net_generic *ng, *old_ng;
BUG_ON(!mutex_is_locked(&net_mutex));
- BUG_ON(id == 0);
+ BUG_ON(id < MIN_PERNET_OPS_ID);
old_ng = rcu_dereference_protected(net->gen,
lockdep_is_held(&net_mutex));
- ng = old_ng;
- if (old_ng->len >= id)
- goto assign;
+ if (old_ng->s.len > id) {
+ old_ng->ptr[id] = data;
+ return 0;
+ }
ng = net_alloc_generic();
if (ng == NULL)
@@ -83,12 +87,12 @@ static int net_assign_generic(struct net *net, int id, void *data)
* the old copy for kfree after a grace period.
*/
- memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*));
+ memcpy(&ng->ptr[MIN_PERNET_OPS_ID], &old_ng->ptr[MIN_PERNET_OPS_ID],
+ (old_ng->s.len - MIN_PERNET_OPS_ID) * sizeof(void *));
+ ng->ptr[id] = data;
rcu_assign_pointer(net->gen, ng);
- kfree_rcu(old_ng, rcu);
-assign:
- ng->ptr[id - 1] = data;
+ kfree_rcu(old_ng, s.rcu);
return 0;
}
@@ -122,8 +126,7 @@ out:
static void ops_free(const struct pernet_operations *ops, struct net *net)
{
if (ops->id && ops->size) {
- int id = *ops->id;
- kfree(net_generic(net, id));
+ kfree(net_generic(net, *ops->id));
}
}
@@ -215,13 +218,16 @@ static void rtnl_net_notifyid(struct net *net, int cmd, int id);
*/
int peernet2id_alloc(struct net *net, struct net *peer)
{
+ unsigned long flags;
bool alloc;
int id;
- spin_lock_bh(&net->nsid_lock);
+ if (atomic_read(&net->count) == 0)
+ return NETNSA_NSID_NOT_ASSIGNED;
+ spin_lock_irqsave(&net->nsid_lock, flags);
alloc = atomic_read(&peer->count) == 0 ? false : true;
id = __peernet2id_alloc(net, peer, &alloc);
- spin_unlock_bh(&net->nsid_lock);
+ spin_unlock_irqrestore(&net->nsid_lock, flags);
if (alloc && id >= 0)
rtnl_net_notifyid(net, RTM_NEWNSID, id);
return id;
@@ -230,11 +236,12 @@ int peernet2id_alloc(struct net *net, struct net *peer)
/* This function returns, if assigned, the id of a peer netns. */
int peernet2id(struct net *net, struct net *peer)
{
+ unsigned long flags;
int id;
- spin_lock_bh(&net->nsid_lock);
+ spin_lock_irqsave(&net->nsid_lock, flags);
id = __peernet2id(net, peer);
- spin_unlock_bh(&net->nsid_lock);
+ spin_unlock_irqrestore(&net->nsid_lock, flags);
return id;
}
EXPORT_SYMBOL(peernet2id);
@@ -249,17 +256,18 @@ bool peernet_has_id(struct net *net, struct net *peer)
struct net *get_net_ns_by_id(struct net *net, int id)
{
+ unsigned long flags;
struct net *peer;
if (id < 0)
return NULL;
rcu_read_lock();
- spin_lock_bh(&net->nsid_lock);
+ spin_lock_irqsave(&net->nsid_lock, flags);
peer = idr_find(&net->netns_ids, id);
if (peer)
get_net(peer);
- spin_unlock_bh(&net->nsid_lock);
+ spin_unlock_irqrestore(&net->nsid_lock, flags);
rcu_read_unlock();
return peer;
@@ -379,7 +387,14 @@ struct net *copy_net_ns(unsigned long flags,
get_user_ns(user_ns);
- mutex_lock(&net_mutex);
+ rv = mutex_lock_killable(&net_mutex);
+ if (rv < 0) {
+ net_free(net);
+ dec_net_namespaces(ucounts);
+ put_user_ns(user_ns);
+ return ERR_PTR(rv);
+ }
+
net->ucounts = ucounts;
rv = setup_net(net, user_ns);
if (rv == 0) {
@@ -422,17 +437,17 @@ static void cleanup_net(struct work_struct *work)
for_each_net(tmp) {
int id;
- spin_lock_bh(&tmp->nsid_lock);
+ spin_lock_irq(&tmp->nsid_lock);
id = __peernet2id(tmp, net);
if (id >= 0)
idr_remove(&tmp->netns_ids, id);
- spin_unlock_bh(&tmp->nsid_lock);
+ spin_unlock_irq(&tmp->nsid_lock);
if (id >= 0)
rtnl_net_notifyid(tmp, RTM_DELNSID, id);
}
- spin_lock_bh(&net->nsid_lock);
+ spin_lock_irq(&net->nsid_lock);
idr_destroy(&net->netns_ids);
- spin_unlock_bh(&net->nsid_lock);
+ spin_unlock_irq(&net->nsid_lock);
}
rtnl_unlock();
@@ -561,6 +576,7 @@ static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh)
{
struct net *net = sock_net(skb->sk);
struct nlattr *tb[NETNSA_MAX + 1];
+ unsigned long flags;
struct net *peer;
int nsid, err;
@@ -581,15 +597,15 @@ static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh)
if (IS_ERR(peer))
return PTR_ERR(peer);
- spin_lock_bh(&net->nsid_lock);
+ spin_lock_irqsave(&net->nsid_lock, flags);
if (__peernet2id(net, peer) >= 0) {
- spin_unlock_bh(&net->nsid_lock);
+ spin_unlock_irqrestore(&net->nsid_lock, flags);
err = -EEXIST;
goto out;
}
err = alloc_netid(net, peer, nsid);
- spin_unlock_bh(&net->nsid_lock);
+ spin_unlock_irqrestore(&net->nsid_lock, flags);
if (err >= 0) {
rtnl_net_notifyid(net, RTM_NEWNSID, err);
err = 0;
@@ -711,10 +727,11 @@ static int rtnl_net_dumpid(struct sk_buff *skb, struct netlink_callback *cb)
.idx = 0,
.s_idx = cb->args[0],
};
+ unsigned long flags;
- spin_lock_bh(&net->nsid_lock);
+ spin_lock_irqsave(&net->nsid_lock, flags);
idr_for_each(&net->netns_ids, rtnl_net_dumpid_one, &net_cb);
- spin_unlock_bh(&net->nsid_lock);
+ spin_unlock_irqrestore(&net->nsid_lock, flags);
cb->args[0] = net_cb.idx;
return skb->len;
@@ -861,7 +878,7 @@ static int register_pernet_operations(struct list_head *list,
if (ops->id) {
again:
- error = ida_get_new_above(&net_generic_ids, 1, ops->id);
+ error = ida_get_new_above(&net_generic_ids, MIN_PERNET_OPS_ID, ops->id);
if (error < 0) {
if (error == -EAGAIN) {
ida_pre_get(&net_generic_ids, GFP_KERNEL);
@@ -869,7 +886,7 @@ again:
}
return error;
}
- max_gen_ptrs = max_t(unsigned int, max_gen_ptrs, *ops->id);
+ max_gen_ptrs = max(max_gen_ptrs, *ops->id + 1);
}
error = __register_pernet_operations(list, ops);
if (error) {