Handle pid namespaces in cgroups code

There's one place that works with task pids - its the "tasks" file in cgroups.
 The read/write handlers assume, that the pid values go to/come from the user
space and thus it is a virtual pid, i.e.  the pid as it is seen from inside a
namespace.

Tune the code accordingly.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Pavel Emelyanov 2008-02-07 00:14:47 -08:00 committed by Linus Torvalds
parent b450129554
commit 73507f335f

View file

@ -1269,7 +1269,7 @@ static int attach_task_by_pid(struct cgroup *cgrp, char *pidbuf)
if (pid) {
rcu_read_lock();
tsk = find_task_by_pid(pid);
tsk = find_task_by_vpid(pid);
if (!tsk || tsk->flags & PF_EXITING) {
rcu_read_unlock();
return -ESRCH;
@ -1955,7 +1955,7 @@ static int pid_array_load(pid_t *pidarray, int npids, struct cgroup *cgrp)
while ((tsk = cgroup_iter_next(cgrp, &it))) {
if (unlikely(n == npids))
break;
pidarray[n++] = task_pid_nr(tsk);
pidarray[n++] = task_pid_vnr(tsk);
}
cgroup_iter_end(cgrp, &it);
return n;