Contributors: 24
Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
Andrey Vagin |
280 |
24.37% |
2 |
3.64% |
Al Viro |
205 |
17.84% |
8 |
14.55% |
Christian Brauner |
179 |
15.58% |
8 |
14.55% |
Eric W. Biedermann |
161 |
14.01% |
6 |
10.91% |
Michael Kerrisk |
84 |
7.31% |
2 |
3.64% |
Jakub Kiciński |
76 |
6.61% |
1 |
1.82% |
David Howells |
49 |
4.26% |
4 |
7.27% |
Carlos Neira |
36 |
3.13% |
1 |
1.82% |
Kirill V Tkhai |
21 |
1.83% |
2 |
3.64% |
Linus Torvalds (pre-git) |
20 |
1.74% |
7 |
12.73% |
Eric Biggers |
6 |
0.52% |
1 |
1.82% |
Alexey Dobriyan |
6 |
0.52% |
1 |
1.82% |
Thomas Weißschuh |
5 |
0.44% |
1 |
1.82% |
Christoph Hellwig |
3 |
0.26% |
1 |
1.82% |
Nick Black |
3 |
0.26% |
1 |
1.82% |
Aleksa Sarai |
3 |
0.26% |
1 |
1.82% |
Joe Perches |
3 |
0.26% |
1 |
1.82% |
Vasiliy Kulikov |
2 |
0.17% |
1 |
1.82% |
Art Haas |
2 |
0.17% |
1 |
1.82% |
Lukas Bulwahn |
1 |
0.09% |
1 |
1.82% |
Arjan van de Ven |
1 |
0.09% |
1 |
1.82% |
Josef 'Jeff' Sipek |
1 |
0.09% |
1 |
1.82% |
Greg Kroah-Hartman |
1 |
0.09% |
1 |
1.82% |
Linus Torvalds |
1 |
0.09% |
1 |
1.82% |
Total |
1149 |
|
55 |
|
// SPDX-License-Identifier: GPL-2.0
#include <linux/mount.h>
#include <linux/pseudo_fs.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/proc_fs.h>
#include <linux/proc_ns.h>
#include <linux/magic.h>
#include <linux/ktime.h>
#include <linux/seq_file.h>
#include <linux/user_namespace.h>
#include <linux/nsfs.h>
#include <linux/uaccess.h>
#include "internal.h"
static struct vfsmount *nsfs_mnt;
static long ns_ioctl(struct file *filp, unsigned int ioctl,
unsigned long arg);
static const struct file_operations ns_file_operations = {
.llseek = no_llseek,
.unlocked_ioctl = ns_ioctl,
.compat_ioctl = compat_ptr_ioctl,
};
static char *ns_dname(struct dentry *dentry, char *buffer, int buflen)
{
struct inode *inode = d_inode(dentry);
struct ns_common *ns = inode->i_private;
const struct proc_ns_operations *ns_ops = ns->ops;
return dynamic_dname(buffer, buflen, "%s:[%lu]",
ns_ops->name, inode->i_ino);
}
const struct dentry_operations ns_dentry_operations = {
.d_delete = always_delete_dentry,
.d_dname = ns_dname,
.d_prune = stashed_dentry_prune,
};
static void nsfs_evict(struct inode *inode)
{
struct ns_common *ns = inode->i_private;
clear_inode(inode);
ns->ops->put(ns);
}
int ns_get_path_cb(struct path *path, ns_get_path_helper_t *ns_get_cb,
void *private_data)
{
struct ns_common *ns;
ns = ns_get_cb(private_data);
if (!ns)
return -ENOENT;
return path_from_stashed(&ns->stashed, nsfs_mnt, ns, path);
}
struct ns_get_path_task_args {
const struct proc_ns_operations *ns_ops;
struct task_struct *task;
};
static struct ns_common *ns_get_path_task(void *private_data)
{
struct ns_get_path_task_args *args = private_data;
return args->ns_ops->get(args->task);
}
int ns_get_path(struct path *path, struct task_struct *task,
const struct proc_ns_operations *ns_ops)
{
struct ns_get_path_task_args args = {
.ns_ops = ns_ops,
.task = task,
};
return ns_get_path_cb(path, ns_get_path_task, &args);
}
int open_related_ns(struct ns_common *ns,
struct ns_common *(*get_ns)(struct ns_common *ns))
{
struct path path = {};
struct ns_common *relative;
struct file *f;
int err;
int fd;
fd = get_unused_fd_flags(O_CLOEXEC);
if (fd < 0)
return fd;
relative = get_ns(ns);
if (IS_ERR(relative)) {
put_unused_fd(fd);
return PTR_ERR(relative);
}
err = path_from_stashed(&relative->stashed, nsfs_mnt, relative, &path);
if (err < 0) {
put_unused_fd(fd);
return err;
}
f = dentry_open(&path, O_RDONLY, current_cred());
path_put(&path);
if (IS_ERR(f)) {
put_unused_fd(fd);
fd = PTR_ERR(f);
} else
fd_install(fd, f);
return fd;
}
EXPORT_SYMBOL_GPL(open_related_ns);
static long ns_ioctl(struct file *filp, unsigned int ioctl,
unsigned long arg)
{
struct user_namespace *user_ns;
struct ns_common *ns = get_proc_ns(file_inode(filp));
uid_t __user *argp;
uid_t uid;
switch (ioctl) {
case NS_GET_USERNS:
return open_related_ns(ns, ns_get_owner);
case NS_GET_PARENT:
if (!ns->ops->get_parent)
return -EINVAL;
return open_related_ns(ns, ns->ops->get_parent);
case NS_GET_NSTYPE:
return ns->ops->type;
case NS_GET_OWNER_UID:
if (ns->ops->type != CLONE_NEWUSER)
return -EINVAL;
user_ns = container_of(ns, struct user_namespace, ns);
argp = (uid_t __user *) arg;
uid = from_kuid_munged(current_user_ns(), user_ns->owner);
return put_user(uid, argp);
default:
return -ENOTTY;
}
}
int ns_get_name(char *buf, size_t size, struct task_struct *task,
const struct proc_ns_operations *ns_ops)
{
struct ns_common *ns;
int res = -ENOENT;
const char *name;
ns = ns_ops->get(task);
if (ns) {
name = ns_ops->real_ns_name ? : ns_ops->name;
res = snprintf(buf, size, "%s:[%u]", name, ns->inum);
ns_ops->put(ns);
}
return res;
}
bool proc_ns_file(const struct file *file)
{
return file->f_op == &ns_file_operations;
}
/**
* ns_match() - Returns true if current namespace matches dev/ino provided.
* @ns: current namespace
* @dev: dev_t from nsfs that will be matched against current nsfs
* @ino: ino_t from nsfs that will be matched against current nsfs
*
* Return: true if dev and ino matches the current nsfs.
*/
bool ns_match(const struct ns_common *ns, dev_t dev, ino_t ino)
{
return (ns->inum == ino) && (nsfs_mnt->mnt_sb->s_dev == dev);
}
static int nsfs_show_path(struct seq_file *seq, struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
const struct ns_common *ns = inode->i_private;
const struct proc_ns_operations *ns_ops = ns->ops;
seq_printf(seq, "%s:[%lu]", ns_ops->name, inode->i_ino);
return 0;
}
static const struct super_operations nsfs_ops = {
.statfs = simple_statfs,
.evict_inode = nsfs_evict,
.show_path = nsfs_show_path,
};
static int nsfs_init_inode(struct inode *inode, void *data)
{
struct ns_common *ns = data;
inode->i_private = data;
inode->i_mode |= S_IRUGO;
inode->i_fop = &ns_file_operations;
inode->i_ino = ns->inum;
return 0;
}
static void nsfs_put_data(void *data)
{
struct ns_common *ns = data;
ns->ops->put(ns);
}
static const struct stashed_operations nsfs_stashed_ops = {
.init_inode = nsfs_init_inode,
.put_data = nsfs_put_data,
};
static int nsfs_init_fs_context(struct fs_context *fc)
{
struct pseudo_fs_context *ctx = init_pseudo(fc, NSFS_MAGIC);
if (!ctx)
return -ENOMEM;
ctx->ops = &nsfs_ops;
ctx->dops = &ns_dentry_operations;
fc->s_fs_info = (void *)&nsfs_stashed_ops;
return 0;
}
static struct file_system_type nsfs = {
.name = "nsfs",
.init_fs_context = nsfs_init_fs_context,
.kill_sb = kill_anon_super,
};
void __init nsfs_init(void)
{
nsfs_mnt = kern_mount(&nsfs);
if (IS_ERR(nsfs_mnt))
panic("can't set nsfs up\n");
nsfs_mnt->mnt_sb->s_flags &= ~SB_NOUSER;
}