#include <linux/syscalls.h>
#include <linux/err.h>
#include <linux/acct.h>
+#include <linux/slab.h>
+#include <linux/proc_fs.h>
+#include <linux/reboot.h>
#define BITS_PER_PAGE (PAGE_SIZE*8)
{
struct pid_namespace *ns;
unsigned int level = parent_pid_ns->level + 1;
- int i;
+ int i, err = -ENOMEM;
ns = kmem_cache_zalloc(pid_ns_cachep, GFP_KERNEL);
if (ns == NULL)
for (i = 1; i < PIDMAP_ENTRIES; i++)
atomic_set(&ns->pidmap[i].nr_free, BITS_PER_PAGE);
+ err = pid_ns_prepare_proc(ns);
+ if (err)
+ goto out_put_parent_pid_ns;
+
return ns;
+out_put_parent_pid_ns:
+ put_pid_ns(parent_pid_ns);
out_free_map:
kfree(ns->pidmap[0].page);
out_free:
kmem_cache_free(pid_ns_cachep, ns);
out:
- return ERR_PTR(-ENOMEM);
+ return ERR_PTR(err);
}
static void destroy_pid_namespace(struct pid_namespace *ns)
{
if (!(flags & CLONE_NEWPID))
return get_pid_ns(old_ns);
- if (flags & CLONE_THREAD)
+ if (flags & (CLONE_THREAD|CLONE_PARENT))
return ERR_PTR(-EINVAL);
return create_pid_namespace(old_ns);
}
while (nr > 0) {
rcu_read_lock();
- /*
- * Use force_sig() since it clears SIGNAL_UNKILLABLE ensuring
- * any nested-container's init processes don't ignore the
- * signal
- */
task = pid_task(find_vpid(nr), PIDTYPE_PID);
- if (task)
- force_sig(SIGKILL, task);
+ if (task && !__fatal_signal_pending(task))
+ send_sig_info(SIGKILL, SEND_SIG_FORCED, task);
rcu_read_unlock();
rc = sys_wait4(-1, NULL, __WALL, NULL);
} while (rc != -ECHILD);
+ if (pid_ns->reboot)
+ current->signal->group_exit_code = pid_ns->reboot;
+
acct_exit_ns(pid_ns);
return;
}
+static int pid_ns_ctl_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table tmp = *table;
+
+ if (write && !capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ /*
+ * Writing directly to ns' last_pid field is OK, since this field
+ * is volatile in a living namespace anyway and a code writing to
+ * it should synchronize its usage with external means.
+ */
+
+ tmp.data = ¤t->nsproxy->pid_ns->last_pid;
+ return proc_dointvec(&tmp, write, buffer, lenp, ppos);
+}
+
+static struct ctl_table pid_ns_ctl_table[] = {
+ {
+ .procname = "ns_last_pid",
+ .maxlen = sizeof(int),
+ .mode = 0666, /* permissions are checked in the handler */
+ .proc_handler = pid_ns_ctl_handler,
+ },
+ { }
+};
+
+static struct ctl_path kern_path[] = { { .procname = "kernel", }, { } };
+
+int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
+{
+ if (pid_ns == &init_pid_ns)
+ return 0;
+
+ switch (cmd) {
+ case LINUX_REBOOT_CMD_RESTART2:
+ case LINUX_REBOOT_CMD_RESTART:
+ pid_ns->reboot = SIGHUP;
+ break;
+
+ case LINUX_REBOOT_CMD_POWER_OFF:
+ case LINUX_REBOOT_CMD_HALT:
+ pid_ns->reboot = SIGINT;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ read_lock(&tasklist_lock);
+ force_sig(SIGKILL, pid_ns->child_reaper);
+ read_unlock(&tasklist_lock);
+
+ do_exit(0);
+
+ /* Not reached */
+ return 0;
+}
+
static __init int pid_namespaces_init(void)
{
pid_ns_cachep = KMEM_CACHE(pid_namespace, SLAB_PANIC);
+ register_sysctl_paths(kern_path, pid_ns_ctl_table);
return 0;
}