ALSA: usb-audio: add support for Akai MPD16
[safe/jmp/linux-2.6] / kernel / pid_namespace.c
index fab8ea8..a5aff94 100644 (file)
@@ -13,6 +13,7 @@
 #include <linux/syscalls.h>
 #include <linux/err.h>
 #include <linux/acct.h>
+#include <linux/slab.h>
 
 #define BITS_PER_PAGE          (PAGE_SIZE*8)
 
@@ -67,9 +68,10 @@ err_alloc:
        return NULL;
 }
 
-static struct pid_namespace *create_pid_namespace(unsigned int level)
+static struct pid_namespace *create_pid_namespace(struct pid_namespace *parent_pid_ns)
 {
        struct pid_namespace *ns;
+       unsigned int level = parent_pid_ns->level + 1;
        int i;
 
        ns = kmem_cache_zalloc(pid_ns_cachep, GFP_KERNEL);
@@ -86,6 +88,7 @@ static struct pid_namespace *create_pid_namespace(unsigned int level)
 
        kref_init(&ns->kref);
        ns->level = level;
+       ns->parent = get_pid_ns(parent_pid_ns);
 
        set_bit(0, ns->pidmap[0].page);
        atomic_set(&ns->pidmap[0].nr_free, BITS_PER_PAGE - 1);
@@ -114,25 +117,11 @@ static void destroy_pid_namespace(struct pid_namespace *ns)
 
 struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *old_ns)
 {
-       struct pid_namespace *new_ns;
-
-       BUG_ON(!old_ns);
-       new_ns = get_pid_ns(old_ns);
        if (!(flags & CLONE_NEWPID))
-               goto out;
-
-       new_ns = ERR_PTR(-EINVAL);
-       if (flags & CLONE_THREAD)
-               goto out_put;
-
-       new_ns = create_pid_namespace(old_ns->level + 1);
-       if (!IS_ERR(new_ns))
-               new_ns->parent = get_pid_ns(old_ns);
-
-out_put:
-       put_pid_ns(old_ns);
-out:
-       return new_ns;
+               return get_pid_ns(old_ns);
+       if (flags & (CLONE_THREAD|CLONE_PARENT))
+               return ERR_PTR(-EINVAL);
+       return create_pid_namespace(old_ns);
 }
 
 void free_pid_ns(struct kref *kref)
@@ -152,6 +141,7 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
 {
        int nr;
        int rc;
+       struct task_struct *task;
 
        /*
         * The last thread in the cgroup-init thread group is terminating.
@@ -169,7 +159,18 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
        read_lock(&tasklist_lock);
        nr = next_pidmap(pid_ns, 1);
        while (nr > 0) {
-               kill_proc_info(SIGKILL, SEND_SIG_PRIV, nr);
+               rcu_read_lock();
+
+               /*
+                * Any nested-container's init processes won't ignore the
+                * SEND_SIG_NOINFO signal, see send_signal()->si_fromuser().
+                */
+               task = pid_task(find_vpid(nr), PIDTYPE_PID);
+               if (task)
+                       send_sig_info(SIGKILL, SEND_SIG_NOINFO, task);
+
+               rcu_read_unlock();
+
                nr = next_pidmap(pid_ns, nr);
        }
        read_unlock(&tasklist_lock);