userns: Convert taskstats to handle the user and pid namespaces.
- Explicitly limit exit task stat broadcast to the initial user and
pid namespaces, as it is already limited to the initial network
namespace.
- For broadcast task stats explicitly generate all of the idenitiers
in terms of the initial user namespace and the initial pid
namespace.
- For request stats report them in terms of the current user namespace
and the current pid namespace. Netlink messages are delivered
syncrhonously to the kernel allowing us to get the user namespace
and the pid namespace from the current task.
- Pass the namespaces for representing pids and uids and gids
into bacct_add_task.
Cc: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index d0a3279..3880df2 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -27,6 +27,7 @@
#include <linux/cgroup.h>
#include <linux/fs.h>
#include <linux/file.h>
+#include <linux/pid_namespace.h>
#include <net/genetlink.h>
#include <linux/atomic.h>
@@ -174,7 +175,9 @@
up_write(&listeners->sem);
}
-static void fill_stats(struct task_struct *tsk, struct taskstats *stats)
+static void fill_stats(struct user_namespace *user_ns,
+ struct pid_namespace *pid_ns,
+ struct task_struct *tsk, struct taskstats *stats)
{
memset(stats, 0, sizeof(*stats));
/*
@@ -190,7 +193,7 @@
stats->version = TASKSTATS_VERSION;
stats->nvcsw = tsk->nvcsw;
stats->nivcsw = tsk->nivcsw;
- bacct_add_tsk(stats, tsk);
+ bacct_add_tsk(user_ns, pid_ns, stats, tsk);
/* fill in extended acct fields */
xacct_add_tsk(stats, tsk);
@@ -207,7 +210,7 @@
rcu_read_unlock();
if (!tsk)
return -ESRCH;
- fill_stats(tsk, stats);
+ fill_stats(current_user_ns(), task_active_pid_ns(current), tsk, stats);
put_task_struct(tsk);
return 0;
}
@@ -291,6 +294,12 @@
if (!cpumask_subset(mask, cpu_possible_mask))
return -EINVAL;
+ if (current_user_ns() != &init_user_ns)
+ return -EINVAL;
+
+ if (task_active_pid_ns(current) != &init_pid_ns)
+ return -EINVAL;
+
if (isadd == REGISTER) {
for_each_cpu(cpu, mask) {
s = kmalloc_node(sizeof(struct listener),
@@ -631,11 +640,12 @@
if (rc < 0)
return;
- stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid);
+ stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID,
+ task_pid_nr_ns(tsk, &init_pid_ns));
if (!stats)
goto err;
- fill_stats(tsk, stats);
+ fill_stats(&init_user_ns, &init_pid_ns, tsk, stats);
/*
* Doesn't matter if tsk is the leader or the last group member leaving
@@ -643,7 +653,8 @@
if (!is_thread_group || !group_dead)
goto send;
- stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tsk->tgid);
+ stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID,
+ task_tgid_nr_ns(tsk, &init_pid_ns));
if (!stats)
goto err;
