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 | |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 16 | #include <linux/slab.h> |
Paul Gortmaker | 9984de1 | 2011-05-23 14:51:41 -0400 | [diff] [blame] | 17 | #include <linux/export.h> |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 18 | #include <linux/nsproxy.h> |
Serge E. Hallyn | 0437eb5 | 2006-10-02 02:18:07 -0700 | [diff] [blame] | 19 | #include <linux/init_task.h> |
Kirill Korotaev | 6b3286e | 2006-12-08 02:37:56 -0800 | [diff] [blame] | 20 | #include <linux/mnt_namespace.h> |
Serge E. Hallyn | 4865ecf | 2006-10-02 02:18:14 -0700 | [diff] [blame] | 21 | #include <linux/utsname.h> |
Cedric Le Goater | 9a575a9 | 2006-12-08 02:37:59 -0800 | [diff] [blame] | 22 | #include <linux/pid_namespace.h> |
Eric W. Biederman | 9dd776b | 2007-09-26 22:04:26 -0700 | [diff] [blame] | 23 | #include <net/net_namespace.h> |
Pavel Emelyanov | ae5e1b2 | 2008-02-08 04:18:22 -0800 | [diff] [blame] | 24 | #include <linux/ipc_namespace.h> |
Eric W. Biederman | 0663c6f | 2010-03-07 17:48:52 -0800 | [diff] [blame] | 25 | #include <linux/proc_fs.h> |
| 26 | #include <linux/file.h> |
| 27 | #include <linux/syscalls.h> |
Serge E. Hallyn | 0437eb5 | 2006-10-02 02:18:07 -0700 | [diff] [blame] | 28 | |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 29 | static struct kmem_cache *nsproxy_cachep; |
| 30 | |
Alexey Dobriyan | 8467005 | 2010-03-10 15:23:10 -0800 | [diff] [blame] | 31 | struct nsproxy init_nsproxy = { |
| 32 | .count = ATOMIC_INIT(1), |
| 33 | .uts_ns = &init_uts_ns, |
| 34 | #if defined(CONFIG_POSIX_MQUEUE) || defined(CONFIG_SYSVIPC) |
| 35 | .ipc_ns = &init_ipc_ns, |
| 36 | #endif |
| 37 | .mnt_ns = NULL, |
| 38 | .pid_ns = &init_pid_ns, |
| 39 | #ifdef CONFIG_NET |
| 40 | .net_ns = &init_net, |
| 41 | #endif |
| 42 | }; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 43 | |
Alexey Dobriyan | 90af90d | 2009-06-17 16:27:56 -0700 | [diff] [blame] | 44 | static inline struct nsproxy *create_nsproxy(void) |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 45 | { |
Alexey Dobriyan | 90af90d | 2009-06-17 16:27:56 -0700 | [diff] [blame] | 46 | struct nsproxy *nsproxy; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 47 | |
Alexey Dobriyan | 90af90d | 2009-06-17 16:27:56 -0700 | [diff] [blame] | 48 | nsproxy = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL); |
| 49 | if (nsproxy) |
| 50 | atomic_set(&nsproxy->count, 1); |
| 51 | return nsproxy; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 52 | } |
| 53 | |
| 54 | /* |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 55 | * Create new nsproxy and all of its the associated namespaces. |
| 56 | * Return the newly created nsproxy. Do not attach this to the task, |
| 57 | * 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] | 58 | */ |
Eric W. Biederman | 213dd26 | 2007-07-15 23:41:15 -0700 | [diff] [blame] | 59 | static struct nsproxy *create_new_namespaces(unsigned long flags, |
| 60 | struct task_struct *tsk, struct fs_struct *new_fs) |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 61 | { |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 62 | struct nsproxy *new_nsp; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 63 | int err; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 64 | |
Alexey Dobriyan | 90af90d | 2009-06-17 16:27:56 -0700 | [diff] [blame] | 65 | new_nsp = create_nsproxy(); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 66 | if (!new_nsp) |
| 67 | return ERR_PTR(-ENOMEM); |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 68 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 69 | 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] | 70 | if (IS_ERR(new_nsp->mnt_ns)) { |
| 71 | err = PTR_ERR(new_nsp->mnt_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 72 | goto out_ns; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 73 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 74 | |
Serge E. Hallyn | bb96a6f | 2011-03-23 16:43:18 -0700 | [diff] [blame] | 75 | new_nsp->uts_ns = copy_utsname(flags, tsk); |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 76 | if (IS_ERR(new_nsp->uts_ns)) { |
| 77 | err = PTR_ERR(new_nsp->uts_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 78 | goto out_uts; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 79 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 80 | |
Serge E. Hallyn | b0e7759 | 2011-03-23 16:43:24 -0700 | [diff] [blame] | 81 | new_nsp->ipc_ns = copy_ipcs(flags, tsk); |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 82 | if (IS_ERR(new_nsp->ipc_ns)) { |
| 83 | err = PTR_ERR(new_nsp->ipc_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 84 | goto out_ipc; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 85 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 86 | |
Sukadev Bhattiprolu | 2894d650 | 2007-10-18 23:39:49 -0700 | [diff] [blame] | 87 | 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] | 88 | if (IS_ERR(new_nsp->pid_ns)) { |
| 89 | err = PTR_ERR(new_nsp->pid_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 90 | goto out_pid; |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 91 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 92 | |
Eric W. Biederman | 9dd776b | 2007-09-26 22:04:26 -0700 | [diff] [blame] | 93 | new_nsp->net_ns = copy_net_ns(flags, tsk->nsproxy->net_ns); |
| 94 | if (IS_ERR(new_nsp->net_ns)) { |
| 95 | err = PTR_ERR(new_nsp->net_ns); |
| 96 | goto out_net; |
| 97 | } |
| 98 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 99 | return new_nsp; |
| 100 | |
Eric W. Biederman | 9dd776b | 2007-09-26 22:04:26 -0700 | [diff] [blame] | 101 | out_net: |
Cedric Le Goater | acce292 | 2007-07-15 23:40:59 -0700 | [diff] [blame] | 102 | if (new_nsp->pid_ns) |
| 103 | put_pid_ns(new_nsp->pid_ns); |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 104 | out_pid: |
| 105 | if (new_nsp->ipc_ns) |
| 106 | put_ipc_ns(new_nsp->ipc_ns); |
| 107 | out_ipc: |
| 108 | if (new_nsp->uts_ns) |
| 109 | put_uts_ns(new_nsp->uts_ns); |
| 110 | out_uts: |
| 111 | if (new_nsp->mnt_ns) |
| 112 | put_mnt_ns(new_nsp->mnt_ns); |
| 113 | out_ns: |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 114 | kmem_cache_free(nsproxy_cachep, new_nsp); |
Cedric Le Goater | 467e9f4 | 2007-07-15 23:41:06 -0700 | [diff] [blame] | 115 | return ERR_PTR(err); |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 116 | } |
| 117 | |
| 118 | /* |
| 119 | * called from clone. This now handles copy for nsproxy and all |
| 120 | * namespaces therein. |
| 121 | */ |
Eric W. Biederman | 213dd26 | 2007-07-15 23:41:15 -0700 | [diff] [blame] | 122 | int copy_namespaces(unsigned long flags, struct task_struct *tsk) |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 123 | { |
| 124 | struct nsproxy *old_ns = tsk->nsproxy; |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 125 | struct nsproxy *new_ns; |
| 126 | int err = 0; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 127 | |
| 128 | if (!old_ns) |
| 129 | return 0; |
| 130 | |
| 131 | get_nsproxy(old_ns); |
| 132 | |
Pavel Emelyanov | 30e49c2 | 2007-10-18 23:40:10 -0700 | [diff] [blame] | 133 | if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
Serge Hallyn | 18b6e04 | 2008-10-15 16:38:45 -0500 | [diff] [blame] | 134 | CLONE_NEWPID | CLONE_NEWNET))) |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 135 | return 0; |
| 136 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 137 | if (!capable(CAP_SYS_ADMIN)) { |
| 138 | err = -EPERM; |
| 139 | goto out; |
| 140 | } |
| 141 | |
Serge E. Hallyn | 02fdb36 | 2008-04-29 01:01:00 -0700 | [diff] [blame] | 142 | /* |
| 143 | * CLONE_NEWIPC must detach from the undolist: after switching |
| 144 | * to a new ipc namespace, the semaphore arrays from the old |
| 145 | * namespace are unreachable. In clone parlance, CLONE_SYSVSEM |
| 146 | * means share undolist with parent, so we must forbid using |
| 147 | * it along with CLONE_NEWIPC. |
| 148 | */ |
| 149 | if ((flags & CLONE_NEWIPC) && (flags & CLONE_SYSVSEM)) { |
| 150 | err = -EINVAL; |
| 151 | goto out; |
| 152 | } |
| 153 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 154 | new_ns = create_new_namespaces(flags, tsk, tsk->fs); |
| 155 | if (IS_ERR(new_ns)) { |
| 156 | err = PTR_ERR(new_ns); |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 157 | goto out; |
| 158 | } |
| 159 | |
| 160 | tsk->nsproxy = new_ns; |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 161 | |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 162 | out: |
Linus Torvalds | 444f378 | 2007-01-30 13:35:18 -0800 | [diff] [blame] | 163 | put_nsproxy(old_ns); |
Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 164 | return err; |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 165 | } |
| 166 | |
| 167 | void free_nsproxy(struct nsproxy *ns) |
| 168 | { |
Cedric Le Goater | 9a575a9 | 2006-12-08 02:37:59 -0800 | [diff] [blame] | 169 | if (ns->mnt_ns) |
| 170 | put_mnt_ns(ns->mnt_ns); |
| 171 | if (ns->uts_ns) |
| 172 | put_uts_ns(ns->uts_ns); |
| 173 | if (ns->ipc_ns) |
| 174 | put_ipc_ns(ns->ipc_ns); |
| 175 | if (ns->pid_ns) |
| 176 | put_pid_ns(ns->pid_ns); |
Eric W. Biederman | 9dd776b | 2007-09-26 22:04:26 -0700 | [diff] [blame] | 177 | put_net(ns->net_ns); |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 178 | kmem_cache_free(nsproxy_cachep, ns); |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 179 | } |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 180 | |
| 181 | /* |
| 182 | * Called from unshare. Unshare all the namespaces part of nsproxy. |
Cedric Le Goater | 4e71e474 | 2007-06-23 17:16:25 -0700 | [diff] [blame] | 183 | * On success, returns the new nsproxy. |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 184 | */ |
| 185 | int unshare_nsproxy_namespaces(unsigned long unshare_flags, |
| 186 | struct nsproxy **new_nsp, struct fs_struct *new_fs) |
| 187 | { |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 188 | int err = 0; |
| 189 | |
Serge E. Hallyn | 77ec739 | 2007-07-15 23:41:01 -0700 | [diff] [blame] | 190 | if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
Serge Hallyn | 18b6e04 | 2008-10-15 16:38:45 -0500 | [diff] [blame] | 191 | CLONE_NEWNET))) |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 192 | return 0; |
| 193 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 194 | if (!capable(CAP_SYS_ADMIN)) |
| 195 | return -EPERM; |
| 196 | |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 197 | *new_nsp = create_new_namespaces(unshare_flags, current, |
| 198 | new_fs ? new_fs : current->fs); |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 199 | if (IS_ERR(*new_nsp)) { |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 200 | err = PTR_ERR(*new_nsp); |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 201 | goto out; |
| 202 | } |
| 203 | |
Serge E. Hallyn | 858d72e | 2007-10-18 23:39:45 -0700 | [diff] [blame] | 204 | out: |
Badari Pulavarty | e3222c4 | 2007-05-08 00:25:21 -0700 | [diff] [blame] | 205 | return err; |
| 206 | } |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 207 | |
Pavel Emelyanov | cf7b708 | 2007-10-18 23:39:54 -0700 | [diff] [blame] | 208 | void switch_task_namespaces(struct task_struct *p, struct nsproxy *new) |
| 209 | { |
| 210 | struct nsproxy *ns; |
| 211 | |
| 212 | might_sleep(); |
| 213 | |
| 214 | ns = p->nsproxy; |
| 215 | |
| 216 | rcu_assign_pointer(p->nsproxy, new); |
| 217 | |
| 218 | if (ns && atomic_dec_and_test(&ns->count)) { |
| 219 | /* |
| 220 | * wait for others to get what they want from this nsproxy. |
| 221 | * |
| 222 | * cannot release this nsproxy via the call_rcu() since |
| 223 | * put_mnt_ns() will want to sleep |
| 224 | */ |
| 225 | synchronize_rcu(); |
| 226 | free_nsproxy(ns); |
| 227 | } |
| 228 | } |
| 229 | |
| 230 | void exit_task_namespaces(struct task_struct *p) |
| 231 | { |
| 232 | switch_task_namespaces(p, NULL); |
| 233 | } |
| 234 | |
Eric W. Biederman | 0663c6f | 2010-03-07 17:48:52 -0800 | [diff] [blame] | 235 | SYSCALL_DEFINE2(setns, int, fd, int, nstype) |
| 236 | { |
| 237 | const struct proc_ns_operations *ops; |
| 238 | struct task_struct *tsk = current; |
| 239 | struct nsproxy *new_nsproxy; |
| 240 | struct proc_inode *ei; |
| 241 | struct file *file; |
| 242 | int err; |
| 243 | |
| 244 | if (!capable(CAP_SYS_ADMIN)) |
| 245 | return -EPERM; |
| 246 | |
| 247 | file = proc_ns_fget(fd); |
| 248 | if (IS_ERR(file)) |
| 249 | return PTR_ERR(file); |
| 250 | |
| 251 | err = -EINVAL; |
| 252 | ei = PROC_I(file->f_dentry->d_inode); |
| 253 | ops = ei->ns_ops; |
| 254 | if (nstype && (ops->type != nstype)) |
| 255 | goto out; |
| 256 | |
| 257 | new_nsproxy = create_new_namespaces(0, tsk, tsk->fs); |
| 258 | if (IS_ERR(new_nsproxy)) { |
| 259 | err = PTR_ERR(new_nsproxy); |
| 260 | goto out; |
| 261 | } |
| 262 | |
| 263 | err = ops->install(new_nsproxy, ei->ns); |
| 264 | if (err) { |
| 265 | free_nsproxy(new_nsproxy); |
| 266 | goto out; |
| 267 | } |
| 268 | switch_task_namespaces(tsk, new_nsproxy); |
| 269 | out: |
| 270 | fput(file); |
| 271 | return err; |
| 272 | } |
| 273 | |
Al Viro | 6657719 | 2011-06-28 15:41:10 -0400 | [diff] [blame] | 274 | int __init nsproxy_cache_init(void) |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 275 | { |
Pavel Emelyanov | db8906d | 2007-10-16 23:30:11 -0700 | [diff] [blame] | 276 | nsproxy_cachep = KMEM_CACHE(nsproxy, SLAB_PANIC); |
Cedric Le Goater | 98c0d07 | 2007-07-15 23:41:07 -0700 | [diff] [blame] | 277 | return 0; |
| 278 | } |