1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_PID_NS_H
3#define _LINUX_PID_NS_H
4
5#include <linux/sched.h>
6#include <linux/bug.h>
7#include <linux/mm.h>
8#include <linux/workqueue.h>
9#include <linux/threads.h>
10#include <linux/nsproxy.h>
11#include <linux/ns_common.h>
12#include <linux/idr.h>
13
14/* MAX_PID_NS_LEVEL is needed for limiting size of 'struct pid' */
15#define MAX_PID_NS_LEVEL 32
16
17struct fs_pin;
18
19#if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE)
20/* modes for vm.memfd_noexec sysctl */
21#define MEMFD_NOEXEC_SCOPE_EXEC 0 /* MFD_EXEC implied if unset */
22#define MEMFD_NOEXEC_SCOPE_NOEXEC_SEAL 1 /* MFD_NOEXEC_SEAL implied if unset */
23#define MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED 2 /* same as 1, except MFD_EXEC rejected */
24#endif
25
26struct pid_namespace {
27 struct idr idr;
28 struct rcu_head rcu;
29 unsigned int pid_allocated;
30 struct task_struct *child_reaper;
31 struct kmem_cache *pid_cachep;
32 unsigned int level;
33 int pid_max;
34 struct pid_namespace *parent;
35#ifdef CONFIG_BSD_PROCESS_ACCT
36 struct fs_pin *bacct;
37#endif
38 struct user_namespace *user_ns;
39 struct ucounts *ucounts;
40 int reboot; /* group exit code if this pidns was rebooted */
41 struct ns_common ns;
42 struct work_struct work;
43#ifdef CONFIG_SYSCTL
44 struct ctl_table_set set;
45 struct ctl_table_header *sysctls;
46#if defined(CONFIG_MEMFD_CREATE)
47 int memfd_noexec_scope;
48#endif
49#endif
50} __randomize_layout;
51
52extern struct pid_namespace init_pid_ns;
53
54#define PIDNS_ADDING (1U << 31)
55
56#ifdef CONFIG_PID_NS
57static inline struct pid_namespace *to_pid_ns(struct ns_common *ns)
58{
59 return container_of(ns, struct pid_namespace, ns);
60}
61
62static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
63{
64 if (ns != &init_pid_ns)
65 ns_ref_inc(ns);
66 return ns;
67}
68
69#if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE)
70static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns)
71{
72 int scope = MEMFD_NOEXEC_SCOPE_EXEC;
73
74 for (; ns; ns = ns->parent)
75 scope = max(scope, READ_ONCE(ns->memfd_noexec_scope));
76
77 return scope;
78}
79#else
80static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns)
81{
82 return 0;
83}
84#endif
85
86extern struct pid_namespace *copy_pid_ns(u64 flags,
87 struct user_namespace *user_ns, struct pid_namespace *ns);
88extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
89extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
90extern void put_pid_ns(struct pid_namespace *ns);
91
92extern bool pidns_is_ancestor(struct pid_namespace *child,
93 struct pid_namespace *ancestor);
94
95#else /* !CONFIG_PID_NS */
96#include <linux/err.h>
97
98static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
99{
100 return ns;
101}
102
103static inline int pidns_memfd_noexec_scope(struct pid_namespace *ns)
104{
105 return 0;
106}
107
108static inline struct pid_namespace *copy_pid_ns(u64 flags,
109 struct user_namespace *user_ns, struct pid_namespace *ns)
110{
111 if (flags & CLONE_NEWPID)
112 ns = ERR_PTR(-EINVAL);
113 return ns;
114}
115
116static inline void put_pid_ns(struct pid_namespace *ns)
117{
118}
119
120static inline void zap_pid_ns_processes(struct pid_namespace *ns)
121{
122 BUG();
123}
124
125static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
126{
127 return 0;
128}
129
130static inline bool pidns_is_ancestor(struct pid_namespace *child,
131 struct pid_namespace *ancestor)
132{
133 return false;
134}
135#endif /* CONFIG_PID_NS */
136
137extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
138void pidhash_init(void);
139void pid_idr_init(void);
140int register_pidns_sysctls(struct pid_namespace *pidns);
141void unregister_pidns_sysctls(struct pid_namespace *pidns);
142
143static inline bool task_is_in_init_pid_ns(struct task_struct *tsk)
144{
145 return task_active_pid_ns(tsk) == &init_pid_ns;
146}
147
148#endif /* _LINUX_PID_NS_H */
149