diff options
Diffstat (limited to 'kernel/pid_namespace.c')
| -rw-r--r-- | kernel/pid_namespace.c | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index fdbd0cdf271..db95d8eb761 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -15,12 +15,10 @@ #include <linux/err.h> #include <linux/acct.h> #include <linux/slab.h> -#include <linux/proc_fs.h> +#include <linux/proc_ns.h> #include <linux/reboot.h> #include <linux/export.h> -#define BITS_PER_PAGE (PAGE_SIZE*8) - struct pid_cache { int nr_ids; char name[16]; @@ -115,6 +113,7 @@ static struct pid_namespace *create_pid_namespace(struct user_namespace *user_ns ns->level = level; ns->parent = get_pid_ns(parent_pid_ns); ns->user_ns = get_user_ns(user_ns); + ns->nr_hashed = PIDNS_HASH_ADDING; INIT_WORK(&ns->proc_work, proc_cleanup_work); set_bit(0, ns->pidmap[0].page); @@ -133,6 +132,12 @@ out: return ERR_PTR(err); } +static void delayed_free_pidns(struct rcu_head *p) +{ + kmem_cache_free(pid_ns_cachep, + container_of(p, struct pid_namespace, rcu)); +} + static void destroy_pid_namespace(struct pid_namespace *ns) { int i; @@ -141,7 +146,7 @@ static void destroy_pid_namespace(struct pid_namespace *ns) for (i = 0; i < PIDMAP_ENTRIES; i++) kfree(ns->pidmap[i].page); put_user_ns(ns->user_ns); - kmem_cache_free(pid_ns_cachep, ns); + call_rcu(&ns->rcu, delayed_free_pidns); } struct pid_namespace *copy_pid_ns(unsigned long flags, @@ -180,6 +185,10 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns) int nr; int rc; struct task_struct *task, *me = current; + int init_pids = thread_group_leader(me) ? 1 : 2; + + /* Don't allow any more processes into the pid namespace */ + disable_pid_allocation(pid_ns); /* Ignore SIGCHLD causing any terminated children to autoreap */ spin_lock_irq(&me->sighand->siglock); @@ -226,7 +235,7 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns) */ for (;;) { set_current_state(TASK_UNINTERRUPTIBLE); - if (pid_ns->nr_hashed == 1) + if (pid_ns->nr_hashed == init_pids) break; schedule(); } @@ -309,7 +318,9 @@ static void *pidns_get(struct task_struct *task) struct pid_namespace *ns; rcu_read_lock(); - ns = get_pid_ns(task_active_pid_ns(task)); + ns = task_active_pid_ns(task); + if (ns) + get_pid_ns(ns); rcu_read_unlock(); return ns; @@ -326,7 +337,7 @@ static int pidns_install(struct nsproxy *nsproxy, void *ns) struct pid_namespace *ancestor, *new = ns; if (!ns_capable(new->user_ns, CAP_SYS_ADMIN) || - !nsown_capable(CAP_SYS_ADMIN)) + !ns_capable(current_user_ns(), CAP_SYS_ADMIN)) return -EPERM; /* @@ -346,8 +357,8 @@ static int pidns_install(struct nsproxy *nsproxy, void *ns) if (ancestor != active) return -EINVAL; - put_pid_ns(nsproxy->pid_ns); - nsproxy->pid_ns = get_pid_ns(new); + put_pid_ns(nsproxy->pid_ns_for_children); + nsproxy->pid_ns_for_children = get_pid_ns(new); return 0; } |