diff options
| author | Andrey Vagin <avagin@openvz.org> | 2016-10-24 18:29:13 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-10-31 10:56:36 -0400 |
| commit | c62cce2caee558e18aa05c01c2fd3b40f07174f2 (patch) | |
| tree | f652d443eb8394c24772bcee4cf15f3a1a6586f1 | |
| parent | 2a43ca0aa9084c41aaa1006fbf22155b2e94babf (diff) | |
net: add an ioctl to get a socket network namespace
Each socket operates in a network namespace where it has been created,
so if we want to dump and restore a socket, we have to know its network
namespace.
We have a socket_diag to get information about sockets, it doesn't
report sockets which are not bound or connected.
This patch introduces a new socket ioctl, which is called SIOCGSKNS
and used to get a file descriptor for a socket network namespace.
A task must have CAP_NET_ADMIN in a target network namespace to
use this ioctl.
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | fs/nsfs.c | 2 | ||||
| -rw-r--r-- | include/linux/proc_fs.h | 4 | ||||
| -rw-r--r-- | include/uapi/linux/sockios.h | 1 | ||||
| -rw-r--r-- | net/socket.c | 13 |
4 files changed, 19 insertions, 1 deletions
diff --git a/fs/nsfs.c b/fs/nsfs.c index 8718af895eab..8c9fb29c6673 100644 --- a/fs/nsfs.c +++ b/fs/nsfs.c @@ -118,7 +118,7 @@ again: return ret; } -static int open_related_ns(struct ns_common *ns, +int open_related_ns(struct ns_common *ns, struct ns_common *(*get_ns)(struct ns_common *ns)) { struct path path = {}; diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index b97bf2ef996e..368c7ad06ae5 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -82,4 +82,8 @@ static inline struct proc_dir_entry *proc_net_mkdir( return proc_mkdir_data(name, 0, parent, net); } +struct ns_common; +int open_related_ns(struct ns_common *ns, + struct ns_common *(*get_ns)(struct ns_common *ns)); + #endif /* _LINUX_PROC_FS_H */ diff --git a/include/uapi/linux/sockios.h b/include/uapi/linux/sockios.h index 8e7890b26d9a..83cc54ce6081 100644 --- a/include/uapi/linux/sockios.h +++ b/include/uapi/linux/sockios.h @@ -84,6 +84,7 @@ #define SIOCWANDEV 0x894A /* get/set netdev parameters */ #define SIOCOUTQNSD 0x894B /* output queue size (not sent only) */ +#define SIOCGSKNS 0x894C /* get socket network namespace */ /* ARP cache control calls. */ /* 0x8950 - 0x8952 * obsolete calls, don't re-use */ diff --git a/net/socket.c b/net/socket.c index 5a9bf5ee2464..970a7ea3fc4a 100644 --- a/net/socket.c +++ b/net/socket.c @@ -877,6 +877,11 @@ static long sock_do_ioctl(struct net *net, struct socket *sock, * what to do with it - that's up to the protocol still. */ +static struct ns_common *get_net_ns(struct ns_common *ns) +{ + return &get_net(container_of(ns, struct net, ns))->ns; +} + static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg) { struct socket *sock; @@ -945,6 +950,13 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg) err = dlci_ioctl_hook(cmd, argp); mutex_unlock(&dlci_ioctl_mutex); break; + case SIOCGSKNS: + err = -EPERM; + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) + break; + + err = open_related_ns(&net->ns, get_net_ns); + break; default: err = sock_do_ioctl(net, sock, cmd, arg); break; @@ -3093,6 +3105,7 @@ static int compat_sock_ioctl_trans(struct file *file, struct socket *sock, case SIOCSIFVLAN: case SIOCADDDLCI: case SIOCDELDLCI: + case SIOCGSKNS: return sock_ioctl(file, cmd, arg); case SIOCGIFFLAGS: |