From f063052947f770845a6252f7fa24f6f624592a24 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 4 May 2011 17:51:50 -0700 Subject: net: Allow setting the network namespace by fd Take advantage of the new abstraction and allow network devices to be placed in any network namespace that we have a fd to talk about. Acked-by: David S. Miller Acked-by: Daniel Lezcano Signed-off-by: Eric W. Biederman --- include/linux/if_link.h | 1 + include/net/net_namespace.h | 1 + net/core/net_namespace.c | 33 +++++++++++++++++++++++++++++++-- net/core/rtnetlink.c | 5 ++++- 4 files changed, 37 insertions(+), 3 deletions(-) diff --git a/include/linux/if_link.h b/include/linux/if_link.h index f4a2e6b..0ee969a 100644 --- a/include/linux/if_link.h +++ b/include/linux/if_link.h @@ -136,6 +136,7 @@ enum { IFLA_PORT_SELF, IFLA_AF_SPEC, IFLA_GROUP, /* Group the device belongs to */ + IFLA_NET_NS_FD, __IFLA_MAX }; diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 3ae4919..dcc8f57 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -119,6 +119,7 @@ static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns) extern struct list_head net_namespace_list; extern struct net *get_net_ns_by_pid(pid_t pid); +extern struct net *get_net_ns_by_fd(int pid); #ifdef CONFIG_NET_NS extern void __put_net(struct net *net); diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index bf7707e..b7403ff 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -8,6 +8,8 @@ #include #include #include +#include +#include #include #include @@ -343,6 +345,28 @@ struct net *get_net_ns_by_pid(pid_t pid) } EXPORT_SYMBOL_GPL(get_net_ns_by_pid); +struct net *get_net_ns_by_fd(int fd) +{ + struct proc_inode *ei; + struct file *file; + struct net *net; + + net = ERR_PTR(-EINVAL); + file = proc_ns_fget(fd); + if (!file) + goto out; + + ei = PROC_I(file->f_dentry->d_inode); + if (ei->ns_ops != &netns_operations) + goto out; + + net = get_net(ei->ns); +out: + if (file) + fput(file); + return net; +} + static int __init net_ns_init(void) { struct net_generic *ng; @@ -577,10 +601,15 @@ EXPORT_SYMBOL_GPL(unregister_pernet_device); #ifdef CONFIG_NET_NS static void *netns_get(struct task_struct *task) { - struct net *net; + struct net *net = NULL; + struct nsproxy *nsproxy; + rcu_read_lock(); - net = get_net(task->nsproxy->net_ns); + nsproxy = task_nsproxy(task); + if (nsproxy) + net = get_net(nsproxy->net_ns); rcu_read_unlock(); + return net; } diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index d7c4bb4..dca9602 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1043,6 +1043,7 @@ const struct nla_policy ifla_policy[IFLA_MAX+1] = { [IFLA_LINKMODE] = { .type = NLA_U8 }, [IFLA_LINKINFO] = { .type = NLA_NESTED }, [IFLA_NET_NS_PID] = { .type = NLA_U32 }, + [IFLA_NET_NS_FD] = { .type = NLA_U32 }, [IFLA_IFALIAS] = { .type = NLA_STRING, .len = IFALIASZ-1 }, [IFLA_VFINFO_LIST] = {. type = NLA_NESTED }, [IFLA_VF_PORTS] = { .type = NLA_NESTED }, @@ -1091,6 +1092,8 @@ struct net *rtnl_link_get_net(struct net *src_net, struct nlattr *tb[]) */ if (tb[IFLA_NET_NS_PID]) net = get_net_ns_by_pid(nla_get_u32(tb[IFLA_NET_NS_PID])); + else if (tb[IFLA_NET_NS_FD]) + net = get_net_ns_by_fd(nla_get_u32(tb[IFLA_NET_NS_FD])); else net = get_net(src_net); return net; @@ -1221,7 +1224,7 @@ static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm, int send_addr_notify = 0; int err; - if (tb[IFLA_NET_NS_PID]) { + if (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD]) { struct net *net = rtnl_link_get_net(dev_net(dev), tb); if (IS_ERR(net)) { err = PTR_ERR(net); -- cgit v1.1