* Pavel Emelianov <xemul@openvz.org>
*/
+#include <linux/slab.h>
#include <linux/module.h>
-#include <linux/version.h>
+#include <linux/syslog.h>
#include <linux/nsproxy.h>
#include <linux/init_task.h>
#include <linux/mnt_namespace.h>
#include <linux/utsname.h>
#include <linux/pid_namespace.h>
+#include <net/net_namespace.h>
+#include <linux/ipc_namespace.h>
static struct kmem_cache *nsproxy_cachep;
-struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy);
-
-static inline void get_nsproxy(struct nsproxy *ns)
-{
- atomic_inc(&ns->count);
-}
-
-void get_task_namespaces(struct task_struct *tsk)
-{
- struct nsproxy *ns = tsk->nsproxy;
- if (ns) {
- get_nsproxy(ns);
- }
-}
-
-/*
- * creates a copy of "orig" with refcount 1.
- */
-static inline struct nsproxy *clone_nsproxy(struct nsproxy *orig)
+struct nsproxy init_nsproxy = {
+ .count = ATOMIC_INIT(1),
+ .uts_ns = &init_uts_ns,
+#if defined(CONFIG_POSIX_MQUEUE) || defined(CONFIG_SYSVIPC)
+ .ipc_ns = &init_ipc_ns,
+#endif
+ .mnt_ns = NULL,
+ .pid_ns = &init_pid_ns,
+#ifdef CONFIG_NET
+ .net_ns = &init_net,
+#endif
+};
+
+static inline struct nsproxy *create_nsproxy(void)
{
- struct nsproxy *ns;
+ struct nsproxy *nsproxy;
- ns = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL);
- if (ns) {
- memcpy(ns, orig, sizeof(struct nsproxy));
- atomic_set(&ns->count, 1);
- }
- return ns;
+ nsproxy = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL);
+ if (nsproxy)
+ atomic_set(&nsproxy->count, 1);
+ return nsproxy;
}
/*
struct nsproxy *new_nsp;
int err;
- new_nsp = clone_nsproxy(tsk->nsproxy);
+ new_nsp = create_nsproxy();
if (!new_nsp)
return ERR_PTR(-ENOMEM);
goto out_ipc;
}
- new_nsp->pid_ns = copy_pid_ns(flags, tsk->nsproxy->pid_ns);
+ new_nsp->pid_ns = copy_pid_ns(flags, task_active_pid_ns(tsk));
if (IS_ERR(new_nsp->pid_ns)) {
err = PTR_ERR(new_nsp->pid_ns);
goto out_pid;
}
- new_nsp->user_ns = copy_user_ns(flags, tsk->nsproxy->user_ns);
- if (IS_ERR(new_nsp->user_ns)) {
- err = PTR_ERR(new_nsp->user_ns);
- goto out_user;
+ new_nsp->net_ns = copy_net_ns(flags, tsk->nsproxy->net_ns);
+ if (IS_ERR(new_nsp->net_ns)) {
+ err = PTR_ERR(new_nsp->net_ns);
+ goto out_net;
+ }
+
+ new_nsp->syslog_ns = copy_syslog_ns(flags, tsk->nsproxy->syslog_ns);
+ if (IS_ERR(new_nsp->syslog_ns)) {
+ err = PTR_ERR(new_nsp->syslog_ns);
+ goto out_syslog;
}
return new_nsp;
-out_user:
+out_syslog:
+ if (new_nsp->net_ns)
+ put_net(new_nsp->net_ns);
+out_net:
if (new_nsp->pid_ns)
put_pid_ns(new_nsp->pid_ns);
out_pid:
get_nsproxy(old_ns);
- if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | CLONE_NEWUSER)))
+ if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
+ CLONE_NEWPID | CLONE_NEWNET)))
return 0;
if (!capable(CAP_SYS_ADMIN)) {
goto out;
}
+ /*
+ * CLONE_NEWIPC must detach from the undolist: after switching
+ * to a new ipc namespace, the semaphore arrays from the old
+ * namespace are unreachable. In clone parlance, CLONE_SYSVSEM
+ * means share undolist with parent, so we must forbid using
+ * it along with CLONE_NEWIPC.
+ */
+ if ((flags & CLONE_NEWIPC) && (flags & CLONE_SYSVSEM)) {
+ err = -EINVAL;
+ goto out;
+ }
+
new_ns = create_new_namespaces(flags, tsk, tsk->fs);
if (IS_ERR(new_ns)) {
err = PTR_ERR(new_ns);
}
tsk->nsproxy = new_ns;
+
out:
put_nsproxy(old_ns);
return err;
void free_nsproxy(struct nsproxy *ns)
{
+ if (ns->syslog_ns)
+ put_syslog_ns(ns->syslog_ns);
if (ns->mnt_ns)
put_mnt_ns(ns->mnt_ns);
if (ns->uts_ns)
put_ipc_ns(ns->ipc_ns);
if (ns->pid_ns)
put_pid_ns(ns->pid_ns);
- if (ns->user_ns)
- put_user_ns(ns->user_ns);
+ put_net(ns->net_ns);
kmem_cache_free(nsproxy_cachep, ns);
}
int err = 0;
if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
- CLONE_NEWUSER)))
+ CLONE_NEWNET)))
return 0;
if (!capable(CAP_SYS_ADMIN))
*new_nsp = create_new_namespaces(unshare_flags, current,
new_fs ? new_fs : current->fs);
- if (IS_ERR(*new_nsp))
+ if (IS_ERR(*new_nsp)) {
err = PTR_ERR(*new_nsp);
+ goto out;
+ }
+
+ err = ns_cgroup_clone(current, task_pid(current));
+ if (err)
+ put_nsproxy(*new_nsp);
+
+out:
return err;
}
+void switch_task_namespaces(struct task_struct *p, struct nsproxy *new)
+{
+ struct nsproxy *ns;
+
+ might_sleep();
+
+ ns = p->nsproxy;
+
+ rcu_assign_pointer(p->nsproxy, new);
+
+ if (ns && atomic_dec_and_test(&ns->count)) {
+ /*
+ * wait for others to get what they want from this nsproxy.
+ *
+ * cannot release this nsproxy via the call_rcu() since
+ * put_mnt_ns() will want to sleep
+ */
+ synchronize_rcu();
+ free_nsproxy(ns);
+ }
+}
+
+void exit_task_namespaces(struct task_struct *p)
+{
+ switch_task_namespaces(p, NULL);
+}
+
static int __init nsproxy_cache_init(void)
{
- nsproxy_cachep = kmem_cache_create("nsproxy", sizeof(struct nsproxy),
- 0, SLAB_PANIC, NULL);
+ nsproxy_cachep = KMEM_CACHE(nsproxy, SLAB_PANIC);
return 0;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff