5.4-stable review patch. If anyone has any objections, please let me know.
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From: Yajun Deng yajun.deng@linux.dev
[ Upstream commit 41467d2ff4dfe1837cbb0f45e2088e6e787580c6 ]
There is only one caller for ops_free(), so inline it. Separate net_drop_ns() and net_free(), so the net_free() can be called directly. Add free_exit_list() helper function for free net_exit_list.
==================== v2: - v1 does not apply, rebase it. ====================
Signed-off-by: Yajun Deng yajun.deng@linux.dev Signed-off-by: David S. Miller davem@davemloft.net Stable-dep-of: 46841c7053e6 ("gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().") Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/net_namespace.c | 52 +++++++++++++++++++--------------------- 1 file changed, 24 insertions(+), 28 deletions(-)
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index c94179d30d426..c4bcedc06822b 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -98,7 +98,7 @@ static int net_assign_generic(struct net *net, unsigned int id, void *data) }
ng = net_alloc_generic(); - if (ng == NULL) + if (!ng) return -ENOMEM;
/* @@ -155,13 +155,6 @@ static int ops_init(const struct pernet_operations *ops, struct net *net) return err; }
-static void ops_free(const struct pernet_operations *ops, struct net *net) -{ - if (ops->id && ops->size) { - kfree(net_generic(net, *ops->id)); - } -} - static void ops_pre_exit_list(const struct pernet_operations *ops, struct list_head *net_exit_list) { @@ -193,7 +186,7 @@ static void ops_free_list(const struct pernet_operations *ops, struct net *net; if (ops->size && ops->id) { list_for_each_entry(net, net_exit_list, exit_list) - ops_free(ops, net); + kfree(net_generic(net, *ops->id)); } }
@@ -448,15 +441,18 @@ static struct net *net_alloc(void)
static void net_free(struct net *net) { - kfree(rcu_access_pointer(net->gen)); - kmem_cache_free(net_cachep, net); + if (refcount_dec_and_test(&net->passive)) { + kfree(rcu_access_pointer(net->gen)); + kmem_cache_free(net_cachep, net); + } }
void net_drop_ns(void *p) { - struct net *ns = p; - if (ns && refcount_dec_and_test(&ns->passive)) - net_free(ns); + struct net *net = (struct net *)p; + + if (net) + net_free(net); }
struct net *copy_net_ns(unsigned long flags, @@ -496,7 +492,7 @@ struct net *copy_net_ns(unsigned long flags, key_remove_domain(net->key_domain); #endif put_user_ns(user_ns); - net_drop_ns(net); + net_free(net); dec_ucounts: dec_net_namespaces(ucounts); return ERR_PTR(rv); @@ -630,7 +626,7 @@ static void cleanup_net(struct work_struct *work) key_remove_domain(net->key_domain); #endif put_user_ns(net->user_ns); - net_drop_ns(net); + net_free(net); } }
@@ -1150,6 +1146,14 @@ static int __init net_ns_init(void)
pure_initcall(net_ns_init);
+static void free_exit_list(struct pernet_operations *ops, struct list_head *net_exit_list) +{ + ops_pre_exit_list(ops, net_exit_list); + synchronize_rcu(); + ops_exit_list(ops, net_exit_list); + ops_free_list(ops, net_exit_list); +} + #ifdef CONFIG_NET_NS static int __register_pernet_operations(struct list_head *list, struct pernet_operations *ops) @@ -1175,10 +1179,7 @@ static int __register_pernet_operations(struct list_head *list, out_undo: /* If I have an error cleanup all namespaces I initialized */ list_del(&ops->list); - ops_pre_exit_list(ops, &net_exit_list); - synchronize_rcu(); - ops_exit_list(ops, &net_exit_list); - ops_free_list(ops, &net_exit_list); + free_exit_list(ops, &net_exit_list); return error; }
@@ -1191,10 +1192,8 @@ static void __unregister_pernet_operations(struct pernet_operations *ops) /* See comment in __register_pernet_operations() */ for_each_net(net) list_add_tail(&net->exit_list, &net_exit_list); - ops_pre_exit_list(ops, &net_exit_list); - synchronize_rcu(); - ops_exit_list(ops, &net_exit_list); - ops_free_list(ops, &net_exit_list); + + free_exit_list(ops, &net_exit_list); }
#else @@ -1217,10 +1216,7 @@ static void __unregister_pernet_operations(struct pernet_operations *ops) } else { LIST_HEAD(net_exit_list); list_add(&init_net.exit_list, &net_exit_list); - ops_pre_exit_list(ops, &net_exit_list); - synchronize_rcu(); - ops_exit_list(ops, &net_exit_list); - ops_free_list(ops, &net_exit_list); + free_exit_list(ops, &net_exit_list); } }