| 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> | 
 | 17 | #include <linux/version.h> | 
 | 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> | 
| Serge E. Hallyn | 0437eb5 | 2006-10-02 02:18:07 -0700 | [diff] [blame] | 23 |  | 
 | 24 | struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); | 
| Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 25 |  | 
 | 26 | static inline void get_nsproxy(struct nsproxy *ns) | 
 | 27 | { | 
 | 28 | 	atomic_inc(&ns->count); | 
 | 29 | } | 
 | 30 |  | 
 | 31 | void get_task_namespaces(struct task_struct *tsk) | 
 | 32 | { | 
 | 33 | 	struct nsproxy *ns = tsk->nsproxy; | 
 | 34 | 	if (ns) { | 
 | 35 | 		get_nsproxy(ns); | 
 | 36 | 	} | 
 | 37 | } | 
 | 38 |  | 
 | 39 | /* | 
 | 40 |  * creates a copy of "orig" with refcount 1. | 
 | 41 |  * This does not grab references to the contained namespaces, | 
 | 42 |  * so that needs to be done by dup_namespaces. | 
 | 43 |  */ | 
 | 44 | static inline struct nsproxy *clone_namespaces(struct nsproxy *orig) | 
 | 45 | { | 
 | 46 | 	struct nsproxy *ns; | 
 | 47 |  | 
| Alexey Dobriyan | e05d722 | 2006-10-19 23:29:12 -0700 | [diff] [blame] | 48 | 	ns = kmemdup(orig, sizeof(struct nsproxy), GFP_KERNEL); | 
| Eric W. Biederman | 5f8442e | 2006-12-13 00:34:04 -0800 | [diff] [blame] | 49 | 	if (ns) | 
| Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 50 | 		atomic_set(&ns->count, 1); | 
| Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 51 | 	return ns; | 
 | 52 | } | 
 | 53 |  | 
 | 54 | /* | 
 | 55 |  * copies the nsproxy, setting refcount to 1, and grabbing a | 
 | 56 |  * reference to all contained namespaces.  Called from | 
 | 57 |  * sys_unshare() | 
 | 58 |  */ | 
 | 59 | struct nsproxy *dup_namespaces(struct nsproxy *orig) | 
 | 60 | { | 
 | 61 | 	struct nsproxy *ns = clone_namespaces(orig); | 
 | 62 |  | 
| Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 63 | 	if (ns) { | 
| Kirill Korotaev | 6b3286e | 2006-12-08 02:37:56 -0800 | [diff] [blame] | 64 | 		if (ns->mnt_ns) | 
 | 65 | 			get_mnt_ns(ns->mnt_ns); | 
| Serge E. Hallyn | 4865ecf | 2006-10-02 02:18:14 -0700 | [diff] [blame] | 66 | 		if (ns->uts_ns) | 
 | 67 | 			get_uts_ns(ns->uts_ns); | 
| Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 68 | 		if (ns->ipc_ns) | 
 | 69 | 			get_ipc_ns(ns->ipc_ns); | 
| Cedric Le Goater | 9a575a9 | 2006-12-08 02:37:59 -0800 | [diff] [blame] | 70 | 		if (ns->pid_ns) | 
 | 71 | 			get_pid_ns(ns->pid_ns); | 
| Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 72 | 	} | 
 | 73 |  | 
| Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 74 | 	return ns; | 
 | 75 | } | 
 | 76 |  | 
 | 77 | /* | 
 | 78 |  * called from clone.  This now handles copy for nsproxy and all | 
 | 79 |  * namespaces therein. | 
 | 80 |  */ | 
 | 81 | int copy_namespaces(int flags, struct task_struct *tsk) | 
 | 82 | { | 
 | 83 | 	struct nsproxy *old_ns = tsk->nsproxy; | 
| Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 84 | 	struct nsproxy *new_ns; | 
 | 85 | 	int err = 0; | 
| Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 86 |  | 
 | 87 | 	if (!old_ns) | 
 | 88 | 		return 0; | 
 | 89 |  | 
 | 90 | 	get_nsproxy(old_ns); | 
 | 91 |  | 
| Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 92 | 	if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC))) | 
| Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 93 | 		return 0; | 
 | 94 |  | 
 | 95 | 	new_ns = clone_namespaces(old_ns); | 
 | 96 | 	if (!new_ns) { | 
 | 97 | 		err = -ENOMEM; | 
 | 98 | 		goto out; | 
 | 99 | 	} | 
 | 100 |  | 
 | 101 | 	tsk->nsproxy = new_ns; | 
 | 102 |  | 
| Kirill Korotaev | 6b3286e | 2006-12-08 02:37:56 -0800 | [diff] [blame] | 103 | 	err = copy_mnt_ns(flags, tsk); | 
| Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 104 | 	if (err) | 
 | 105 | 		goto out_ns; | 
| Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 106 |  | 
| Serge E. Hallyn | 4865ecf | 2006-10-02 02:18:14 -0700 | [diff] [blame] | 107 | 	err = copy_utsname(flags, tsk); | 
| Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 108 | 	if (err) | 
 | 109 | 		goto out_uts; | 
 | 110 |  | 
 | 111 | 	err = copy_ipcs(flags, tsk); | 
 | 112 | 	if (err) | 
 | 113 | 		goto out_ipc; | 
| Serge E. Hallyn | 4865ecf | 2006-10-02 02:18:14 -0700 | [diff] [blame] | 114 |  | 
| Cedric Le Goater | 9a575a9 | 2006-12-08 02:37:59 -0800 | [diff] [blame] | 115 | 	err = copy_pid_ns(flags, tsk); | 
 | 116 | 	if (err) | 
 | 117 | 		goto out_pid; | 
 | 118 |  | 
| Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 119 | out: | 
| Linus Torvalds | 444f378 | 2007-01-30 13:35:18 -0800 | [diff] [blame] | 120 | 	put_nsproxy(old_ns); | 
| Serge E. Hallyn | 1651e14 | 2006-10-02 02:18:08 -0700 | [diff] [blame] | 121 | 	return err; | 
| Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 122 |  | 
| Cedric Le Goater | 9a575a9 | 2006-12-08 02:37:59 -0800 | [diff] [blame] | 123 | out_pid: | 
 | 124 | 	if (new_ns->ipc_ns) | 
 | 125 | 		put_ipc_ns(new_ns->ipc_ns); | 
| Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 126 | out_ipc: | 
 | 127 | 	if (new_ns->uts_ns) | 
 | 128 | 		put_uts_ns(new_ns->uts_ns); | 
 | 129 | out_uts: | 
| Kirill Korotaev | 6b3286e | 2006-12-08 02:37:56 -0800 | [diff] [blame] | 130 | 	if (new_ns->mnt_ns) | 
 | 131 | 		put_mnt_ns(new_ns->mnt_ns); | 
| Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 132 | out_ns: | 
 | 133 | 	tsk->nsproxy = old_ns; | 
| Pavel | 5d124e9 | 2006-10-02 02:18:24 -0700 | [diff] [blame] | 134 | 	kfree(new_ns); | 
| Kirill Korotaev | 25b21cb | 2006-10-02 02:18:19 -0700 | [diff] [blame] | 135 | 	goto out; | 
| Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 136 | } | 
 | 137 |  | 
 | 138 | void free_nsproxy(struct nsproxy *ns) | 
 | 139 | { | 
| Cedric Le Goater | 9a575a9 | 2006-12-08 02:37:59 -0800 | [diff] [blame] | 140 | 	if (ns->mnt_ns) | 
 | 141 | 		put_mnt_ns(ns->mnt_ns); | 
 | 142 | 	if (ns->uts_ns) | 
 | 143 | 		put_uts_ns(ns->uts_ns); | 
 | 144 | 	if (ns->ipc_ns) | 
 | 145 | 		put_ipc_ns(ns->ipc_ns); | 
 | 146 | 	if (ns->pid_ns) | 
 | 147 | 		put_pid_ns(ns->pid_ns); | 
 | 148 | 	kfree(ns); | 
| Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 149 | } |