diff options
Diffstat (limited to 'kernel/nsproxy.c')
| -rw-r--r-- | kernel/nsproxy.c | 138 |
1 files changed, 82 insertions, 56 deletions
diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index f74e6c00e26..8e7811086b8 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -14,7 +14,7 @@ */ #include <linux/slab.h> -#include <linux/module.h> +#include <linux/export.h> #include <linux/nsproxy.h> #include <linux/init_task.h> #include <linux/mnt_namespace.h> @@ -22,19 +22,22 @@ #include <linux/pid_namespace.h> #include <net/net_namespace.h> #include <linux/ipc_namespace.h> +#include <linux/proc_ns.h> +#include <linux/file.h> +#include <linux/syscalls.h> static struct kmem_cache *nsproxy_cachep; struct nsproxy init_nsproxy = { - .count = ATOMIC_INIT(1), - .uts_ns = &init_uts_ns, + .count = ATOMIC_INIT(1), + .uts_ns = &init_uts_ns, #if defined(CONFIG_POSIX_MQUEUE) || defined(CONFIG_SYSVIPC) - .ipc_ns = &init_ipc_ns, + .ipc_ns = &init_ipc_ns, #endif - .mnt_ns = NULL, - .pid_ns = &init_pid_ns, + .mnt_ns = NULL, + .pid_ns_for_children = &init_pid_ns, #ifdef CONFIG_NET - .net_ns = &init_net, + .net_ns = &init_net, #endif }; @@ -54,7 +57,8 @@ static inline struct nsproxy *create_nsproxy(void) * leave it to the caller to do proper locking and attach it to task. */ static struct nsproxy *create_new_namespaces(unsigned long flags, - struct task_struct *tsk, struct fs_struct *new_fs) + struct task_struct *tsk, struct user_namespace *user_ns, + struct fs_struct *new_fs) { struct nsproxy *new_nsp; int err; @@ -63,31 +67,32 @@ static struct nsproxy *create_new_namespaces(unsigned long flags, if (!new_nsp) return ERR_PTR(-ENOMEM); - new_nsp->mnt_ns = copy_mnt_ns(flags, tsk->nsproxy->mnt_ns, new_fs); + new_nsp->mnt_ns = copy_mnt_ns(flags, tsk->nsproxy->mnt_ns, user_ns, new_fs); if (IS_ERR(new_nsp->mnt_ns)) { err = PTR_ERR(new_nsp->mnt_ns); goto out_ns; } - new_nsp->uts_ns = copy_utsname(flags, tsk->nsproxy->uts_ns); + new_nsp->uts_ns = copy_utsname(flags, user_ns, tsk->nsproxy->uts_ns); if (IS_ERR(new_nsp->uts_ns)) { err = PTR_ERR(new_nsp->uts_ns); goto out_uts; } - new_nsp->ipc_ns = copy_ipcs(flags, tsk->nsproxy->ipc_ns); + new_nsp->ipc_ns = copy_ipcs(flags, user_ns, tsk->nsproxy->ipc_ns); if (IS_ERR(new_nsp->ipc_ns)) { err = PTR_ERR(new_nsp->ipc_ns); goto out_ipc; } - 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); + new_nsp->pid_ns_for_children = + copy_pid_ns(flags, user_ns, tsk->nsproxy->pid_ns_for_children); + if (IS_ERR(new_nsp->pid_ns_for_children)) { + err = PTR_ERR(new_nsp->pid_ns_for_children); goto out_pid; } - new_nsp->net_ns = copy_net_ns(flags, tsk->nsproxy->net_ns); + new_nsp->net_ns = copy_net_ns(flags, user_ns, tsk->nsproxy->net_ns); if (IS_ERR(new_nsp->net_ns)) { err = PTR_ERR(new_nsp->net_ns); goto out_net; @@ -96,8 +101,8 @@ static struct nsproxy *create_new_namespaces(unsigned long flags, return new_nsp; out_net: - if (new_nsp->pid_ns) - put_pid_ns(new_nsp->pid_ns); + if (new_nsp->pid_ns_for_children) + put_pid_ns(new_nsp->pid_ns_for_children); out_pid: if (new_nsp->ipc_ns) put_ipc_ns(new_nsp->ipc_ns); @@ -119,23 +124,18 @@ out_ns: int copy_namespaces(unsigned long flags, struct task_struct *tsk) { struct nsproxy *old_ns = tsk->nsproxy; + struct user_namespace *user_ns = task_cred_xxx(tsk, user_ns); struct nsproxy *new_ns; - int err = 0; - if (!old_ns) + if (likely(!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | + CLONE_NEWPID | CLONE_NEWNET)))) { + get_nsproxy(old_ns); return 0; - - get_nsproxy(old_ns); - - if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | - CLONE_NEWPID | CLONE_NEWNET))) - return 0; - - if (!capable(CAP_SYS_ADMIN)) { - err = -EPERM; - goto out; } + if (!ns_capable(user_ns, CAP_SYS_ADMIN)) + return -EPERM; + /* * CLONE_NEWIPC must detach from the undolist: after switching * to a new ipc namespace, the semaphore arrays from the old @@ -143,22 +143,16 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk) * 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; - } + if ((flags & (CLONE_NEWIPC | CLONE_SYSVSEM)) == + (CLONE_NEWIPC | CLONE_SYSVSEM)) + return -EINVAL; - new_ns = create_new_namespaces(flags, tsk, tsk->fs); - if (IS_ERR(new_ns)) { - err = PTR_ERR(new_ns); - goto out; - } + new_ns = create_new_namespaces(flags, tsk, user_ns, tsk->fs); + if (IS_ERR(new_ns)) + return PTR_ERR(new_ns); tsk->nsproxy = new_ns; - -out: - put_nsproxy(old_ns); - return err; + return 0; } void free_nsproxy(struct nsproxy *ns) @@ -169,8 +163,8 @@ void free_nsproxy(struct nsproxy *ns) put_uts_ns(ns->uts_ns); if (ns->ipc_ns) put_ipc_ns(ns->ipc_ns); - if (ns->pid_ns) - put_pid_ns(ns->pid_ns); + if (ns->pid_ns_for_children) + put_pid_ns(ns->pid_ns_for_children); put_net(ns->net_ns); kmem_cache_free(nsproxy_cachep, ns); } @@ -180,28 +174,26 @@ void free_nsproxy(struct nsproxy *ns) * On success, returns the new nsproxy. */ int unshare_nsproxy_namespaces(unsigned long unshare_flags, - struct nsproxy **new_nsp, struct fs_struct *new_fs) + struct nsproxy **new_nsp, struct cred *new_cred, struct fs_struct *new_fs) { + struct user_namespace *user_ns; int err = 0; if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | - CLONE_NEWNET))) + CLONE_NEWNET | CLONE_NEWPID))) return 0; - if (!capable(CAP_SYS_ADMIN)) + user_ns = new_cred ? new_cred->user_ns : current_user_ns(); + if (!ns_capable(user_ns, CAP_SYS_ADMIN)) return -EPERM; - *new_nsp = create_new_namespaces(unshare_flags, current, - new_fs ? new_fs : current->fs); + *new_nsp = create_new_namespaces(unshare_flags, current, user_ns, + new_fs ? new_fs : current->fs); 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; } @@ -233,10 +225,44 @@ void exit_task_namespaces(struct task_struct *p) switch_task_namespaces(p, NULL); } -static int __init nsproxy_cache_init(void) +SYSCALL_DEFINE2(setns, int, fd, int, nstype) +{ + const struct proc_ns_operations *ops; + struct task_struct *tsk = current; + struct nsproxy *new_nsproxy; + struct proc_ns *ei; + struct file *file; + int err; + + file = proc_ns_fget(fd); + if (IS_ERR(file)) + return PTR_ERR(file); + + err = -EINVAL; + ei = get_proc_ns(file_inode(file)); + ops = ei->ns_ops; + if (nstype && (ops->type != nstype)) + goto out; + + new_nsproxy = create_new_namespaces(0, tsk, current_user_ns(), tsk->fs); + if (IS_ERR(new_nsproxy)) { + err = PTR_ERR(new_nsproxy); + goto out; + } + + err = ops->install(new_nsproxy, ei->ns); + if (err) { + free_nsproxy(new_nsproxy); + goto out; + } + switch_task_namespaces(tsk, new_nsproxy); +out: + fput(file); + return err; +} + +int __init nsproxy_cache_init(void) { nsproxy_cachep = KMEM_CACHE(nsproxy, SLAB_PANIC); return 0; } - -module_init(nsproxy_cache_init); |
