Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2006 IBM Corporation |
| 3 | * |
| 4 | * Author: Serge Hallyn <serue@us.ibm.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License as |
| 8 | * published by the Free Software Foundation, version 2 of the |
| 9 | * License. |
Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 10 | * |
| 11 | * Jun 2006 - namespaces support |
| 12 | * OpenVZ, SWsoft Inc. |
| 13 | * Pavel Emelianov <xemul@openvz.org> |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 14 | */ |
| 15 | |
| 16 | #include <linux/module.h> |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 17 | #include <linux/nsproxy.h> |
Serge E. Hallyn | 0437eb5 | 2006-10-02 02:18:07 -0700 | [diff] [blame] | 18 | #include <linux/init_task.h> |
Kirill Korotaev | 6b3286e | 2006-12-08 02:37:56 -0800 | [diff] [blame] | 19 | #include <linux/mnt_namespace.h> |
Serge E. Hallyn | 4865ecf | 2006-10-02 02:18:14 -0700 | [diff] [blame] | 20 | #include <linux/utsname.h> |
Cedric Le Goater | 9a575a9 | 2006-12-08 02:37:59 -0800 | [diff] [blame] | 21 | #include <linux/pid_namespace.h> |
Eric W. Biederman | 9dd776b | 2007-09-26 22:04:26 -0700 | [diff] [blame] | 22 | #include <net/net_namespace.h> |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 23 | #include <linux/ipc_namespace.h> |
Serge E. Hallyn | 0437eb5 | 2006-10-02 02:18:07 -0700 | [diff] [blame] | 24 | |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 25 | static struct kmem_cache *nsproxy_cachep; |
| 26 | |
Serge E. Hallyn | 0437eb5 | 2006-10-02 02:18:07 -0700 | [diff] [blame] | 27 | struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 28 | |
Alexey Dobriyan | 90af90d | 2009-06-17 16:27:56 -0700 | [diff] [blame] | 29 | static inline struct nsproxy *create_nsproxy(void) |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 30 | { |
Alexey Dobriyan | 90af90d | 2009-06-17 16:27:56 -0700 | [diff] [blame] | 31 | struct nsproxy *nsproxy; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 32 | |
Alexey Dobriyan | 90af90d | 2009-06-17 16:27:56 -0700 | [diff] [blame] | 33 | nsproxy = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL); |
| 34 | if (nsproxy) |
| 35 | atomic_set(&nsproxy->count, 1); |
| 36 | return nsproxy; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 37 | } |
| 38 | |
| 39 | /* |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 40 | * Create new nsproxy and all of its the associated namespaces. |
| 41 | * Return the newly created nsproxy. Do not attach this to the task, |
| 42 | * leave it to the caller to do proper locking and attach it to task. |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 43 | */ |
Eric W. Biederman | 213dd26 | 2007-07-15 23:41:15 -0700 | [diff] [blame] | 44 | static struct nsproxy *create_new_namespaces(unsigned long flags, |
| 45 | struct task_struct *tsk, struct fs_struct *new_fs) |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 46 | { |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 47 | struct nsproxy *new_nsp; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 48 | int err; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 49 | |
Alexey Dobriyan | 90af90d | 2009-06-17 16:27:56 -0700 | [diff] [blame] | 50 | new_nsp = create_nsproxy(); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 51 | if (!new_nsp) |
| 52 | return ERR_PTR(-ENOMEM); |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 53 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 54 | new_nsp->mnt_ns = copy_mnt_ns(flags, tsk->nsproxy->mnt_ns, new_fs); |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 55 | if (IS_ERR(new_nsp->mnt_ns)) { |
| 56 | err = PTR_ERR(new_nsp->mnt_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 57 | goto out_ns; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 58 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 59 | |
| 60 | new_nsp->uts_ns = copy_utsname(flags, tsk->nsproxy->uts_ns); |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 61 | if (IS_ERR(new_nsp->uts_ns)) { |
| 62 | err = PTR_ERR(new_nsp->uts_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 63 | goto out_uts; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 64 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 65 | |
| 66 | new_nsp->ipc_ns = copy_ipcs(flags, tsk->nsproxy->ipc_ns); |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 67 | if (IS_ERR(new_nsp->ipc_ns)) { |
| 68 | err = PTR_ERR(new_nsp->ipc_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 69 | goto out_ipc; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 70 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 71 | |
Sukadev Bhattiprolu | 2894d650 | 2007-10-18 23:39:49 -0700 | [diff] [blame] | 72 | new_nsp->pid_ns = copy_pid_ns(flags, task_active_pid_ns(tsk)); |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 73 | if (IS_ERR(new_nsp->pid_ns)) { |
| 74 | err = PTR_ERR(new_nsp->pid_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 75 | goto out_pid; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 76 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 77 | |
Eric W. Biederman | 9dd776b | 2007-09-26 22:04:26 -0700 | [diff] [blame] | 78 | new_nsp->net_ns = copy_net_ns(flags, tsk->nsproxy->net_ns); |
| 79 | if (IS_ERR(new_nsp->net_ns)) { |
| 80 | err = PTR_ERR(new_nsp->net_ns); |
| 81 | goto out_net; |
| 82 | } |
| 83 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 84 | return new_nsp; |
| 85 | |
Eric W. Biederman | 9dd776b | 2007-09-26 22:04:26 -0700 | [diff] [blame] | 86 | out_net: |
Cedric Le Goater | acce292 | 2007-07-15 23:40:59 -0700 | [diff] [blame] | 87 | if (new_nsp->pid_ns) |
| 88 | put_pid_ns(new_nsp->pid_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 89 | out_pid: |
| 90 | if (new_nsp->ipc_ns) |
| 91 | put_ipc_ns(new_nsp->ipc_ns); |
| 92 | out_ipc: |
| 93 | if (new_nsp->uts_ns) |
| 94 | put_uts_ns(new_nsp->uts_ns); |
| 95 | out_uts: |
| 96 | if (new_nsp->mnt_ns) |
| 97 | put_mnt_ns(new_nsp->mnt_ns); |
| 98 | out_ns: |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 99 | kmem_cache_free(nsproxy_cachep, new_nsp); |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 100 | return ERR_PTR(err); |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 101 | } |
| 102 | |
| 103 | /* |
| 104 | * called from clone. This now handles copy for nsproxy and all |
| 105 | * namespaces therein. |
| 106 | */ |
Eric W. Biederman | 213dd26 | 2007-07-15 23:41:15 -0700 | [diff] [blame] | 107 | int copy_namespaces(unsigned long flags, struct task_struct *tsk) |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 108 | { |
| 109 | struct nsproxy *old_ns = tsk->nsproxy; |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 110 | struct nsproxy *new_ns; |
| 111 | int err = 0; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 112 | |
| 113 | if (!old_ns) |
| 114 | return 0; |
| 115 | |
| 116 | get_nsproxy(old_ns); |
| 117 | |
Pavel Emelyanov | 30e49c2 | 2007-10-18 23:40:10 -0700 | [diff] [blame] | 118 | if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
Serge Hallyn | 18b6e04 | 2008-10-15 16:38:45 -0500 | [diff] [blame] | 119 | CLONE_NEWPID | CLONE_NEWNET))) |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 120 | return 0; |
| 121 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 122 | if (!capable(CAP_SYS_ADMIN)) { |
| 123 | err = -EPERM; |
| 124 | goto out; |
| 125 | } |
| 126 | |
Serge E. Hallyn | 02fdb36 | 2008-04-29 01:01:00 -0700 | [diff] [blame] | 127 | /* |
| 128 | * CLONE_NEWIPC must detach from the undolist: after switching |
| 129 | * to a new ipc namespace, the semaphore arrays from the old |
| 130 | * namespace are unreachable. In clone parlance, CLONE_SYSVSEM |
| 131 | * means share undolist with parent, so we must forbid using |
| 132 | * it along with CLONE_NEWIPC. |
| 133 | */ |
| 134 | if ((flags & CLONE_NEWIPC) && (flags & CLONE_SYSVSEM)) { |
| 135 | err = -EINVAL; |
| 136 | goto out; |
| 137 | } |
| 138 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 139 | new_ns = create_new_namespaces(flags, tsk, tsk->fs); |
| 140 | if (IS_ERR(new_ns)) { |
| 141 | err = PTR_ERR(new_ns); |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 142 | goto out; |
| 143 | } |
| 144 | |
| 145 | tsk->nsproxy = new_ns; |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 146 | |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 147 | out: |
Linus Torvalds | 444f378 | 2007-01-30 13:35:18 -0800 | [diff] [blame] | 148 | put_nsproxy(old_ns); |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 149 | return err; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 150 | } |
| 151 | |
| 152 | void free_nsproxy(struct nsproxy *ns) |
| 153 | { |
Cedric Le Goater | 9a575a9 | 2006-12-08 02:37:59 -0800 | [diff] [blame] | 154 | if (ns->mnt_ns) |
| 155 | put_mnt_ns(ns->mnt_ns); |
| 156 | if (ns->uts_ns) |
| 157 | put_uts_ns(ns->uts_ns); |
| 158 | if (ns->ipc_ns) |
| 159 | put_ipc_ns(ns->ipc_ns); |
| 160 | if (ns->pid_ns) |
| 161 | put_pid_ns(ns->pid_ns); |
Eric W. Biederman | 9dd776b | 2007-09-26 22:04:26 -0700 | [diff] [blame] | 162 | put_net(ns->net_ns); |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 163 | kmem_cache_free(nsproxy_cachep, ns); |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 164 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 165 | |
| 166 | /* |
| 167 | * Called from unshare. Unshare all the namespaces part of nsproxy. |
Cedric Le Goater | 4e71e474 | 2007-06-23 17:16:25 -0700 | [diff] [blame] | 168 | * On success, returns the new nsproxy. |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 169 | */ |
| 170 | int unshare_nsproxy_namespaces(unsigned long unshare_flags, |
| 171 | struct nsproxy **new_nsp, struct fs_struct *new_fs) |
| 172 | { |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 173 | int err = 0; |
| 174 | |
Serge E. Hallyn | 77ec739 | 2007-07-15 23:41:01 -0700 | [diff] [blame] | 175 | if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
Serge Hallyn | 18b6e04 | 2008-10-15 16:38:45 -0500 | [diff] [blame] | 176 | CLONE_NEWNET))) |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 177 | return 0; |
| 178 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 179 | if (!capable(CAP_SYS_ADMIN)) |
| 180 | return -EPERM; |
| 181 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 182 | *new_nsp = create_new_namespaces(unshare_flags, current, |
| 183 | new_fs ? new_fs : current->fs); |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 184 | if (IS_ERR(*new_nsp)) { |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 185 | err = PTR_ERR(*new_nsp); |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 186 | goto out; |
| 187 | } |
| 188 | |
Serge E. Hallyn | e885dcd | 2008-07-25 01:47:06 -0700 | [diff] [blame] | 189 | err = ns_cgroup_clone(current, task_pid(current)); |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 190 | if (err) |
| 191 | put_nsproxy(*new_nsp); |
| 192 | |
| 193 | out: |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 194 | return err; |
| 195 | } |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 196 | |
Pavel Emelyanov | cf7b708 | 2007-10-18 23:39:54 -0700 | [diff] [blame] | 197 | void switch_task_namespaces(struct task_struct *p, struct nsproxy *new) |
| 198 | { |
| 199 | struct nsproxy *ns; |
| 200 | |
| 201 | might_sleep(); |
| 202 | |
| 203 | ns = p->nsproxy; |
| 204 | |
| 205 | rcu_assign_pointer(p->nsproxy, new); |
| 206 | |
| 207 | if (ns && atomic_dec_and_test(&ns->count)) { |
| 208 | /* |
| 209 | * wait for others to get what they want from this nsproxy. |
| 210 | * |
| 211 | * cannot release this nsproxy via the call_rcu() since |
| 212 | * put_mnt_ns() will want to sleep |
| 213 | */ |
| 214 | synchronize_rcu(); |
| 215 | free_nsproxy(ns); |
| 216 | } |
| 217 | } |
| 218 | |
| 219 | void exit_task_namespaces(struct task_struct *p) |
| 220 | { |
| 221 | switch_task_namespaces(p, NULL); |
| 222 | } |
| 223 | |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 224 | static int __init nsproxy_cache_init(void) |
| 225 | { |
Pavel Emelyanov | db8906d | 2007-10-16 23:30:11 -0700 | [diff] [blame] | 226 | nsproxy_cachep = KMEM_CACHE(nsproxy, SLAB_PANIC); |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 227 | return 0; |
| 228 | } |
| 229 | |
| 230 | module_init(nsproxy_cache_init); |