proc: make proc entries inherit ownership from parent

There are certain parameters that belong to net namespace and that are
exported in /proc. They should be controllable by the container's owner,
but are currently owned by global root and thus not available.

Let's change proc code to inherit ownership of parent entry, and when
create per-ns "net" proc entry set it up as owned by container's owner.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Dmitry Torokhov 2016-08-10 14:36:01 -07:00 committed by David S. Miller
parent f8c46cb390
commit c110486f6c
2 changed files with 15 additions and 0 deletions

View File

@ -390,6 +390,8 @@ static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent,
atomic_set(&ent->count, 1);
spin_lock_init(&ent->pde_unload_lock);
INIT_LIST_HEAD(&ent->pde_openers);
proc_set_user(ent, (*parent)->uid, (*parent)->gid);
out:
return ent;
}

View File

@ -21,6 +21,7 @@
#include <linux/bitops.h>
#include <linux/mount.h>
#include <linux/nsproxy.h>
#include <linux/uidgid.h>
#include <net/net_namespace.h>
#include <linux/seq_file.h>
@ -185,6 +186,8 @@ const struct file_operations proc_net_operations = {
static __net_init int proc_net_ns_init(struct net *net)
{
struct proc_dir_entry *netd, *net_statd;
kuid_t uid;
kgid_t gid;
int err;
err = -ENOMEM;
@ -199,6 +202,16 @@ static __net_init int proc_net_ns_init(struct net *net)
netd->parent = &proc_root;
memcpy(netd->name, "net", 4);
uid = make_kuid(net->user_ns, 0);
if (!uid_valid(uid))
uid = netd->uid;
gid = make_kgid(net->user_ns, 0);
if (!gid_valid(gid))
gid = netd->gid;
proc_set_user(netd, uid, gid);
err = -EEXIST;
net_statd = proc_net_mkdir(net, "stat", netd);
if (!net_statd)